begriffs open source - cmsis-freertos/blob - Source/queue.c

   1 /*
   2  * FreeRTOS Kernel V10.2.1
   3  * Copyright (C) 2019 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, const BaseType_t xCopyPosition ) 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                 if( uxItemSize == ( UBaseType_t ) 0 )
 377                 {
 378                         /* There is not going to be a queue storage area. */
 379                         xQueueSizeInBytes = ( size_t ) 0;
 380                 }
 381                 else
 382                 {
 383                         /* Allocate enough space to hold the maximum number of items that
 384                         can be in the queue at any time. */
 385                         xQueueSizeInBytes = ( size_t ) ( uxQueueLength * uxItemSize ); /*lint !e961 MISRA exception as the casts are only redundant for some ports. */
 386                 }
 387
 388                 /* Allocate the queue and storage area.  Justification for MISRA
 389                 deviation as follows:  pvPortMalloc() always ensures returned memory
 390                 blocks are aligned per the requirements of the MCU stack.  In this case
 391                 pvPortMalloc() must return a pointer that is guaranteed to meet the
 392                 alignment requirements of the Queue_t structure - which in this case
 393                 is an int8_t *.  Therefore, whenever the stack alignment requirements
 394                 are greater than or equal to the pointer to char requirements the cast
 395                 is safe.  In other cases alignment requirements are not strict (one or
 396                 two bytes). */
 397                 pxNewQueue = ( Queue_t * ) pvPortMalloc( sizeof( Queue_t ) + xQueueSizeInBytes ); /*lint !e9087 !e9079 see comment above. */
 398
 399                 if( pxNewQueue != NULL )
 400                 {
 401                         /* Jump past the queue structure to find the location of the queue
 402                         storage area. */
 403                         pucQueueStorage = ( uint8_t * ) pxNewQueue;
 404                         pucQueueStorage += sizeof( Queue_t ); /*lint !e9016 Pointer arithmetic allowed on char types, especially when it assists conveying intent. */
 405
 406                         #if( configSUPPORT_STATIC_ALLOCATION == 1 )
 407                         {
 408                                 /* Queues can be created either statically or dynamically, so
 409                                 note this task was created dynamically in case it is later
 410                                 deleted. */
 411                                 pxNewQueue->ucStaticallyAllocated = pdFALSE;
 412                         }
 413                         #endif /* configSUPPORT_STATIC_ALLOCATION */
 414
 415                         prvInitialiseNewQueue( uxQueueLength, uxItemSize, pucQueueStorage, ucQueueType, pxNewQueue );
 416                 }
 417                 else
 418                 {
 419                         traceQUEUE_CREATE_FAILED( ucQueueType );
 420                         mtCOVERAGE_TEST_MARKER();
 421                 }
 422
 423                 return pxNewQueue;
 424         }
 425
 426 #endif /* configSUPPORT_STATIC_ALLOCATION */
 427 /*-----------------------------------------------------------*/
 428
 429 static void prvInitialiseNewQueue( const UBaseType_t uxQueueLength, const UBaseType_t uxItemSize, uint8_t *pucQueueStorage, const uint8_t ucQueueType, Queue_t *pxNewQueue )
 430 {
 431         /* Remove compiler warnings about unused parameters should
 432         configUSE_TRACE_FACILITY not be set to 1. */
 433         ( void ) ucQueueType;
 434
 435         if( uxItemSize == ( UBaseType_t ) 0 )
 436         {
 437                 /* No RAM was allocated for the queue storage area, but PC head cannot
 438                 be set to NULL because NULL is used as a key to say the queue is used as
 439                 a mutex.  Therefore just set pcHead to point to the queue as a benign
 440                 value that is known to be within the memory map. */
 441                 pxNewQueue->pcHead = ( int8_t * ) pxNewQueue;
 442         }
 443         else
 444         {
 445                 /* Set the head to the start of the queue storage area. */
 446                 pxNewQueue->pcHead = ( int8_t * ) pucQueueStorage;
 447         }
 448
 449         /* Initialise the queue members as described where the queue type is
 450         defined. */
 451         pxNewQueue->uxLength = uxQueueLength;
 452         pxNewQueue->uxItemSize = uxItemSize;
 453         ( void ) xQueueGenericReset( pxNewQueue, pdTRUE );
 454
 455         #if ( configUSE_TRACE_FACILITY == 1 )
 456         {
 457                 pxNewQueue->ucQueueType = ucQueueType;
 458         }
 459         #endif /* configUSE_TRACE_FACILITY */
 460
 461         #if( configUSE_QUEUE_SETS == 1 )
 462         {
 463                 pxNewQueue->pxQueueSetContainer = NULL;
 464         }
 465         #endif /* configUSE_QUEUE_SETS */
 466
 467         traceQUEUE_CREATE( pxNewQueue );
 468 }
 469 /*-----------------------------------------------------------*/
 470
 471 #if( configUSE_MUTEXES == 1 )
 472
 473         static void prvInitialiseMutex( Queue_t *pxNewQueue )
 474         {
 475                 if( pxNewQueue != NULL )
 476                 {
 477                         /* The queue create function will set all the queue structure members
 478                         correctly for a generic queue, but this function is creating a
 479                         mutex.  Overwrite those members that need to be set differently -
 480                         in particular the information required for priority inheritance. */
 481                         pxNewQueue->u.xSemaphore.xMutexHolder = NULL;
 482                         pxNewQueue->uxQueueType = queueQUEUE_IS_MUTEX;
 483
 484                         /* In case this is a recursive mutex. */
 485                         pxNewQueue->u.xSemaphore.uxRecursiveCallCount = 0;
 486
 487                         traceCREATE_MUTEX( pxNewQueue );
 488
 489                         /* Start with the semaphore in the expected state. */
 490                         ( void ) xQueueGenericSend( pxNewQueue, NULL, ( TickType_t ) 0U, queueSEND_TO_BACK );
 491                 }
 492                 else
 493                 {
 494                         traceCREATE_MUTEX_FAILED();
 495                 }
 496         }
 497
 498 #endif /* configUSE_MUTEXES */
 499 /*-----------------------------------------------------------*/
 500
 501 #if( ( configUSE_MUTEXES == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )
 502
 503         QueueHandle_t xQueueCreateMutex( const uint8_t ucQueueType )
 504         {
 505         QueueHandle_t xNewQueue;
 506         const UBaseType_t uxMutexLength = ( UBaseType_t ) 1, uxMutexSize = ( UBaseType_t ) 0;
 507
 508                 xNewQueue = xQueueGenericCreate( uxMutexLength, uxMutexSize, ucQueueType );
 509                 prvInitialiseMutex( ( Queue_t * ) xNewQueue );
 510
 511                 return xNewQueue;
 512         }
 513
 514 #endif /* configUSE_MUTEXES */
 515 /*-----------------------------------------------------------*/
 516
 517 #if( ( configUSE_MUTEXES == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 1 ) )
 518
 519         QueueHandle_t xQueueCreateMutexStatic( const uint8_t ucQueueType, StaticQueue_t *pxStaticQueue )
 520         {
 521         QueueHandle_t xNewQueue;
 522         const UBaseType_t uxMutexLength = ( UBaseType_t ) 1, uxMutexSize = ( UBaseType_t ) 0;
 523
 524                 /* Prevent compiler warnings about unused parameters if
 525                 configUSE_TRACE_FACILITY does not equal 1. */
 526                 ( void ) ucQueueType;
 527
 528                 xNewQueue = xQueueGenericCreateStatic( uxMutexLength, uxMutexSize, NULL, pxStaticQueue, ucQueueType );
 529                 prvInitialiseMutex( ( Queue_t * ) xNewQueue );
 530
 531                 return xNewQueue;
 532         }
 533
 534 #endif /* configUSE_MUTEXES */
 535 /*-----------------------------------------------------------*/
 536
 537 #if ( ( configUSE_MUTEXES == 1 ) && ( INCLUDE_xSemaphoreGetMutexHolder == 1 ) )
 538
 539         TaskHandle_t xQueueGetMutexHolder( QueueHandle_t xSemaphore )
 540         {
 541         TaskHandle_t pxReturn;
 542         Queue_t * const pxSemaphore = ( Queue_t * ) xSemaphore;
 543
 544                 /* This function is called by xSemaphoreGetMutexHolder(), and should not
 545                 be called directly.  Note:  This is a good way of determining if the
 546                 calling task is the mutex holder, but not a good way of determining the
 547                 identity of the mutex holder, as the holder may change between the
 548                 following critical section exiting and the function returning. */
 549                 taskENTER_CRITICAL();
 550                 {
 551                         if( pxSemaphore->uxQueueType == queueQUEUE_IS_MUTEX )
 552                         {
 553                                 pxReturn = pxSemaphore->u.xSemaphore.xMutexHolder;
 554                         }
 555                         else
 556                         {
 557                                 pxReturn = NULL;
 558                         }
 559                 }
 560                 taskEXIT_CRITICAL();
 561
 562                 return pxReturn;
 563         } /*lint !e818 xSemaphore cannot be a pointer to const because it is a typedef. */
 564
 565 #endif
 566 /*-----------------------------------------------------------*/
 567
 568 #if ( ( configUSE_MUTEXES == 1 ) && ( INCLUDE_xSemaphoreGetMutexHolder == 1 ) )
 569
 570         TaskHandle_t xQueueGetMutexHolderFromISR( QueueHandle_t xSemaphore )
 571         {
 572         TaskHandle_t pxReturn;
 573
 574                 configASSERT( xSemaphore );
 575
 576                 /* Mutexes cannot be used in interrupt service routines, so the mutex
 577                 holder should not change in an ISR, and therefore a critical section is
 578                 not required here. */
 579                 if( ( ( Queue_t * ) xSemaphore )->uxQueueType == queueQUEUE_IS_MUTEX )
 580                 {
 581                         pxReturn = ( ( Queue_t * ) xSemaphore )->u.xSemaphore.xMutexHolder;
 582                 }
 583                 else
 584                 {
 585                         pxReturn = NULL;
 586                 }
 587
 588                 return pxReturn;
 589         } /*lint !e818 xSemaphore cannot be a pointer to const because it is a typedef. */
 590
 591 #endif
 592 /*-----------------------------------------------------------*/
 593
 594 #if ( configUSE_RECURSIVE_MUTEXES == 1 )
 595
 596         BaseType_t xQueueGiveMutexRecursive( QueueHandle_t xMutex )
 597         {
 598         BaseType_t xReturn;
 599         Queue_t * const pxMutex = ( Queue_t * ) xMutex;
 600
 601                 configASSERT( pxMutex );
 602
 603                 /* If this is the task that holds the mutex then xMutexHolder will not
 604                 change outside of this task.  If this task does not hold the mutex then
 605                 pxMutexHolder can never coincidentally equal the tasks handle, and as
 606                 this is the only condition we are interested in it does not matter if
 607                 pxMutexHolder is accessed simultaneously by another task.  Therefore no
 608                 mutual exclusion is required to test the pxMutexHolder variable. */
 609                 if( pxMutex->u.xSemaphore.xMutexHolder == xTaskGetCurrentTaskHandle() )
 610                 {
 611                         traceGIVE_MUTEX_RECURSIVE( pxMutex );
 612
 613                         /* uxRecursiveCallCount cannot be zero if xMutexHolder is equal to
 614                         the task handle, therefore no underflow check is required.  Also,
 615                         uxRecursiveCallCount is only modified by the mutex holder, and as
 616                         there can only be one, no mutual exclusion is required to modify the
 617                         uxRecursiveCallCount member. */
 618                         ( pxMutex->u.xSemaphore.uxRecursiveCallCount )--;
 619
 620                         /* Has the recursive call count unwound to 0? */
 621                         if( pxMutex->u.xSemaphore.uxRecursiveCallCount == ( UBaseType_t ) 0 )
 622                         {
 623                                 /* Return the mutex.  This will automatically unblock any other
 624                                 task that might be waiting to access the mutex. */
 625                                 ( void ) xQueueGenericSend( pxMutex, NULL, queueMUTEX_GIVE_BLOCK_TIME, queueSEND_TO_BACK );
 626                         }
 627                         else
 628                         {
 629                                 mtCOVERAGE_TEST_MARKER();
 630                         }
 631
 632                         xReturn = pdPASS;
 633                 }
 634                 else
 635                 {
 636                         /* The mutex cannot be given because the calling task is not the
 637                         holder. */
 638                         xReturn = pdFAIL;
 639
 640                         traceGIVE_MUTEX_RECURSIVE_FAILED( pxMutex );
 641                 }
 642
 643                 return xReturn;
 644         }
 645
 646 #endif /* configUSE_RECURSIVE_MUTEXES */
 647 /*-----------------------------------------------------------*/
 648
 649 #if ( configUSE_RECURSIVE_MUTEXES == 1 )
 650
 651         BaseType_t xQueueTakeMutexRecursive( QueueHandle_t xMutex, TickType_t xTicksToWait )
 652         {
 653         BaseType_t xReturn;
 654         Queue_t * const pxMutex = ( Queue_t * ) xMutex;
 655
 656                 configASSERT( pxMutex );
 657
 658                 /* Comments regarding mutual exclusion as per those within
 659                 xQueueGiveMutexRecursive(). */
 660
 661                 traceTAKE_MUTEX_RECURSIVE( pxMutex );
 662
 663                 if( pxMutex->u.xSemaphore.xMutexHolder == xTaskGetCurrentTaskHandle() )
 664                 {
 665                         ( pxMutex->u.xSemaphore.uxRecursiveCallCount )++;
 666                         xReturn = pdPASS;
 667                 }
 668                 else
 669                 {
 670                         xReturn = xQueueSemaphoreTake( pxMutex, xTicksToWait );
 671
 672                         /* pdPASS will only be returned if the mutex was successfully
 673                         obtained.  The calling task may have entered the Blocked state
 674                         before reaching here. */
 675                         if( xReturn != pdFAIL )
 676                         {
 677                                 ( pxMutex->u.xSemaphore.uxRecursiveCallCount )++;
 678                         }
 679                         else
 680                         {
 681                                 traceTAKE_MUTEX_RECURSIVE_FAILED( pxMutex );
 682                         }
 683                 }
 684
 685                 return xReturn;
 686         }
 687
 688 #endif /* configUSE_RECURSIVE_MUTEXES */
 689 /*-----------------------------------------------------------*/
 690
 691 #if( ( configUSE_COUNTING_SEMAPHORES == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 1 ) )
 692
 693         QueueHandle_t xQueueCreateCountingSemaphoreStatic( const UBaseType_t uxMaxCount, const UBaseType_t uxInitialCount, StaticQueue_t *pxStaticQueue )
 694         {
 695         QueueHandle_t xHandle;
 696
 697                 configASSERT( uxMaxCount != 0 );
 698                 configASSERT( uxInitialCount <= uxMaxCount );
 699
 700                 xHandle = xQueueGenericCreateStatic( uxMaxCount, queueSEMAPHORE_QUEUE_ITEM_LENGTH, NULL, pxStaticQueue, queueQUEUE_TYPE_COUNTING_SEMAPHORE );
 701
 702                 if( xHandle != NULL )
 703                 {
 704                         ( ( Queue_t * ) xHandle )->uxMessagesWaiting = uxInitialCount;
 705
 706                         traceCREATE_COUNTING_SEMAPHORE();
 707                 }
 708                 else
 709                 {
 710                         traceCREATE_COUNTING_SEMAPHORE_FAILED();
 711                 }
 712
 713                 return xHandle;
 714         }
 715
 716 #endif /* ( ( configUSE_COUNTING_SEMAPHORES == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) ) */
 717 /*-----------------------------------------------------------*/
 718
 719 #if( ( configUSE_COUNTING_SEMAPHORES == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )
 720
 721         QueueHandle_t xQueueCreateCountingSemaphore( const UBaseType_t uxMaxCount, const UBaseType_t uxInitialCount )
 722         {
 723         QueueHandle_t xHandle;
 724
 725                 configASSERT( uxMaxCount != 0 );
 726                 configASSERT( uxInitialCount <= uxMaxCount );
 727
 728                 xHandle = xQueueGenericCreate( uxMaxCount, queueSEMAPHORE_QUEUE_ITEM_LENGTH, queueQUEUE_TYPE_COUNTING_SEMAPHORE );
 729
 730                 if( xHandle != NULL )
 731                 {
 732                         ( ( Queue_t * ) xHandle )->uxMessagesWaiting = uxInitialCount;
 733
 734                         traceCREATE_COUNTING_SEMAPHORE();
 735                 }
 736                 else
 737                 {
 738                         traceCREATE_COUNTING_SEMAPHORE_FAILED();
 739                 }
 740
 741                 return xHandle;
 742         }
 743
 744 #endif /* ( ( configUSE_COUNTING_SEMAPHORES == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) ) */
 745 /*-----------------------------------------------------------*/
 746
 747 BaseType_t xQueueGenericSend( QueueHandle_t xQueue, const void * const pvItemToQueue, TickType_t xTicksToWait, const BaseType_t xCopyPosition )
 748 {
 749 BaseType_t xEntryTimeSet = pdFALSE, xYieldRequired;
 750 TimeOut_t xTimeOut;
 751 Queue_t * const pxQueue = xQueue;
 752
 753         configASSERT( pxQueue );
 754         configASSERT( !( ( pvItemToQueue == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );
 755         configASSERT( !( ( xCopyPosition == queueOVERWRITE ) && ( pxQueue->uxLength != 1 ) ) );
 756         #if ( ( INCLUDE_xTaskGetSchedulerState == 1 ) || ( configUSE_TIMERS == 1 ) )
 757         {
 758                 configASSERT( !( ( xTaskGetSchedulerState() == taskSCHEDULER_SUSPENDED ) && ( xTicksToWait != 0 ) ) );
 759         }
 760         #endif
 761
 762
 763         /*lint -save -e904 This function relaxes the coding standard somewhat to
 764         allow return statements within the function itself.  This is done in the
 765         interest of execution time efficiency. */
 766         for( ;; )
 767         {
 768                 taskENTER_CRITICAL();
 769                 {
 770                         /* Is there room on the queue now?  The running task must be the
 771                         highest priority task wanting to access the queue.  If the head item
 772                         in the queue is to be overwritten then it does not matter if the
 773                         queue is full. */
 774                         if( ( pxQueue->uxMessagesWaiting < pxQueue->uxLength ) || ( xCopyPosition == queueOVERWRITE ) )
 775                         {
 776                                 traceQUEUE_SEND( pxQueue );
 777
 778                                 #if ( configUSE_QUEUE_SETS == 1 )
 779                                 {
 780                                 UBaseType_t uxPreviousMessagesWaiting = pxQueue->uxMessagesWaiting;
 781
 782                                         xYieldRequired = prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );
 783
 784                                         if( pxQueue->pxQueueSetContainer != NULL )
 785                                         {
 786                                                 if( ( xCopyPosition == queueOVERWRITE ) && ( uxPreviousMessagesWaiting != ( UBaseType_t ) 0 ) )
 787                                                 {
 788                                                         /* Do not notify the queue set as an existing item
 789                                                         was overwritten in the queue so the number of items
 790                                                         in the queue has not changed. */
 791                                                         mtCOVERAGE_TEST_MARKER();
 792                                                 }
 793                                                 else if( prvNotifyQueueSetContainer( pxQueue, xCopyPosition ) != pdFALSE )
 794                                                 {
 795                                                         /* The queue is a member of a queue set, and posting
 796                                                         to the queue set caused a higher priority task to
 797                                                         unblock. A context switch is required. */
 798                                                         queueYIELD_IF_USING_PREEMPTION();
 799                                                 }
 800                                                 else
 801                                                 {
 802                                                         mtCOVERAGE_TEST_MARKER();
 803                                                 }
 804                                         }
 805                                         else
 806                                         {
 807                                                 /* If there was a task waiting for data to arrive on the
 808                                                 queue then unblock it now. */
 809                                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
 810                                                 {
 811                                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
 812                                                         {
 813                                                                 /* The unblocked task has a priority higher than
 814                                                                 our own so yield immediately.  Yes it is ok to
 815                                                                 do this from within the critical section - the
 816                                                                 kernel takes care of that. */
 817                                                                 queueYIELD_IF_USING_PREEMPTION();
 818                                                         }
 819                                                         else
 820                                                         {
 821                                                                 mtCOVERAGE_TEST_MARKER();
 822                                                         }
 823                                                 }
 824                                                 else if( xYieldRequired != pdFALSE )
 825                                                 {
 826                                                         /* This path is a special case that will only get
 827                                                         executed if the task was holding multiple mutexes
 828                                                         and the mutexes were given back in an order that is
 829                                                         different to that in which they were taken. */
 830                                                         queueYIELD_IF_USING_PREEMPTION();
 831                                                 }
 832                                                 else
 833                                                 {
 834                                                         mtCOVERAGE_TEST_MARKER();
 835                                                 }
 836                                         }
 837                                 }
 838                                 #else /* configUSE_QUEUE_SETS */
 839                                 {
 840                                         xYieldRequired = prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );
 841
 842                                         /* If there was a task waiting for data to arrive on the
 843                                         queue then unblock it now. */
 844                                         if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
 845                                         {
 846                                                 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
 847                                                 {
 848                                                         /* The unblocked task has a priority higher than
 849                                                         our own so yield immediately.  Yes it is ok to do
 850                                                         this from within the critical section - the kernel
 851                                                         takes care of that. */
 852                                                         queueYIELD_IF_USING_PREEMPTION();
 853                                                 }
 854                                                 else
 855                                                 {
 856                                                         mtCOVERAGE_TEST_MARKER();
 857                                                 }
 858                                         }
 859                                         else if( xYieldRequired != pdFALSE )
 860                                         {
 861                                                 /* This path is a special case that will only get
 862                                                 executed if the task was holding multiple mutexes and
 863                                                 the mutexes were given back in an order that is
 864                                                 different to that in which they were taken. */
 865                                                 queueYIELD_IF_USING_PREEMPTION();
 866                                         }
 867                                         else
 868                                         {
 869                                                 mtCOVERAGE_TEST_MARKER();
 870                                         }
 871                                 }
 872                                 #endif /* configUSE_QUEUE_SETS */
 873
 874                                 taskEXIT_CRITICAL();
 875                                 return pdPASS;
 876                         }
 877                         else
 878                         {
 879                                 if( xTicksToWait == ( TickType_t ) 0 )
 880                                 {
 881                                         /* The queue was full and no block time is specified (or
 882                                         the block time has expired) so leave now. */
 883                                         taskEXIT_CRITICAL();
 884
 885                                         /* Return to the original privilege level before exiting
 886                                         the function. */
 887                                         traceQUEUE_SEND_FAILED( pxQueue );
 888                                         return errQUEUE_FULL;
 889                                 }
 890                                 else if( xEntryTimeSet == pdFALSE )
 891                                 {
 892                                         /* The queue was full and a block time was specified so
 893                                         configure the timeout structure. */
 894                                         vTaskInternalSetTimeOutState( &xTimeOut );
 895                                         xEntryTimeSet = pdTRUE;
 896                                 }
 897                                 else
 898                                 {
 899                                         /* Entry time was already set. */
 900                                         mtCOVERAGE_TEST_MARKER();
 901                                 }
 902                         }
 903                 }
 904                 taskEXIT_CRITICAL();
 905
 906                 /* Interrupts and other tasks can send to and receive from the queue
 907                 now the critical section has been exited. */
 908
 909                 vTaskSuspendAll();
 910                 prvLockQueue( pxQueue );
 911
 912                 /* Update the timeout state to see if it has expired yet. */
 913                 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
 914                 {
 915                         if( prvIsQueueFull( pxQueue ) != pdFALSE )
 916                         {
 917                                 traceBLOCKING_ON_QUEUE_SEND( pxQueue );
 918                                 vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToSend ), xTicksToWait );
 919
 920                                 /* Unlocking the queue means queue events can effect the
 921                                 event list.  It is possible that interrupts occurring now
 922                                 remove this task from the event list again - but as the
 923                                 scheduler is suspended the task will go onto the pending
 924                                 ready last instead of the actual ready list. */
 925                                 prvUnlockQueue( pxQueue );
 926
 927                                 /* Resuming the scheduler will move tasks from the pending
 928                                 ready list into the ready list - so it is feasible that this
 929                                 task is already in a ready list before it yields - in which
 930                                 case the yield will not cause a context switch unless there
 931                                 is also a higher priority task in the pending ready list. */
 932                                 if( xTaskResumeAll() == pdFALSE )
 933                                 {
 934                                         portYIELD_WITHIN_API();
 935                                 }
 936                         }
 937                         else
 938                         {
 939                                 /* Try again. */
 940                                 prvUnlockQueue( pxQueue );
 941                                 ( void ) xTaskResumeAll();
 942                         }
 943                 }
 944                 else
 945                 {
 946                         /* The timeout has expired. */
 947                         prvUnlockQueue( pxQueue );
 948                         ( void ) xTaskResumeAll();
 949
 950                         traceQUEUE_SEND_FAILED( pxQueue );
 951                         return errQUEUE_FULL;
 952                 }
 953         } /*lint -restore */
 954 }
 955 /*-----------------------------------------------------------*/
 956
 957 BaseType_t xQueueGenericSendFromISR( QueueHandle_t xQueue, const void * const pvItemToQueue, BaseType_t * const pxHigherPriorityTaskWoken, const BaseType_t xCopyPosition )
 958 {
 959 BaseType_t xReturn;
 960 UBaseType_t uxSavedInterruptStatus;
 961 Queue_t * const pxQueue = xQueue;
 962
 963         configASSERT( pxQueue );
 964         configASSERT( !( ( pvItemToQueue == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );
 965         configASSERT( !( ( xCopyPosition == queueOVERWRITE ) && ( pxQueue->uxLength != 1 ) ) );
 966
 967         /* RTOS ports that support interrupt nesting have the concept of a maximum
 968         system call (or maximum API call) interrupt priority.  Interrupts that are
 969         above the maximum system call priority are kept permanently enabled, even
 970         when the RTOS kernel is in a critical section, but cannot make any calls to
 971         FreeRTOS API functions.  If configASSERT() is defined in FreeRTOSConfig.h
 972         then portASSERT_IF_INTERRUPT_PRIORITY_INVALID() will result in an assertion
 973         failure if a FreeRTOS API function is called from an interrupt that has been
 974         assigned a priority above the configured maximum system call priority.
 975         Only FreeRTOS functions that end in FromISR can be called from interrupts
 976         that have been assigned a priority at or (logically) below the maximum
 977         system call     interrupt priority.  FreeRTOS maintains a separate interrupt
 978         safe API to ensure interrupt entry is as fast and as simple as possible.
 979         More information (albeit Cortex-M specific) is provided on the following
 980         link: http://www.freertos.org/RTOS-Cortex-M3-M4.html */
 981         portASSERT_IF_INTERRUPT_PRIORITY_INVALID();
 982
 983         /* Similar to xQueueGenericSend, except without blocking if there is no room
 984         in the queue.  Also don't directly wake a task that was blocked on a queue
 985         read, instead return a flag to say whether a context switch is required or
 986         not (i.e. has a task with a higher priority than us been woken by this
 987         post). */
 988         uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
 989         {
 990                 if( ( pxQueue->uxMessagesWaiting < pxQueue->uxLength ) || ( xCopyPosition == queueOVERWRITE ) )
 991                 {
 992                         const int8_t cTxLock = pxQueue->cTxLock;
 993
 994                         traceQUEUE_SEND_FROM_ISR( pxQueue );
 995
 996                         /* Semaphores use xQueueGiveFromISR(), so pxQueue will not be a
 997                         semaphore or mutex.  That means prvCopyDataToQueue() cannot result
 998                         in a task disinheriting a priority and prvCopyDataToQueue() can be
 999                         called here even though the disinherit function does not check if
1000                         the scheduler is suspended before accessing the ready lists. */
1001                         ( void ) prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );
1002
1003                         /* The event list is not altered if the queue is locked.  This will
1004                         be done when the queue is unlocked later. */
1005                         if( cTxLock == queueUNLOCKED )
1006                         {
1007                                 #if ( configUSE_QUEUE_SETS == 1 )
1008                                 {
1009                                         if( pxQueue->pxQueueSetContainer != NULL )
1010                                         {
1011                                                 if( prvNotifyQueueSetContainer( pxQueue, xCopyPosition ) != pdFALSE )
1012                                                 {
1013                                                         /* The queue is a member of a queue set, and posting
1014                                                         to the queue set caused a higher priority task to
1015                                                         unblock.  A context switch is required. */
1016                                                         if( pxHigherPriorityTaskWoken != NULL )
1017                                                         {
1018                                                                 *pxHigherPriorityTaskWoken = pdTRUE;
1019                                                         }
1020                                                         else
1021                                                         {
1022                                                                 mtCOVERAGE_TEST_MARKER();
1023                                                         }
1024                                                 }
1025                                                 else
1026                                                 {
1027                                                         mtCOVERAGE_TEST_MARKER();
1028                                                 }
1029                                         }
1030                                         else
1031                                         {
1032                                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
1033                                                 {
1034                                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
1035                                                         {
1036                                                                 /* The task waiting has a higher priority so
1037                                                                 record that a context switch is required. */
1038                                                                 if( pxHigherPriorityTaskWoken != NULL )
1039                                                                 {
1040                                                                         *pxHigherPriorityTaskWoken = pdTRUE;
1041                                                                 }
1042                                                                 else
1043                                                                 {
1044                                                                         mtCOVERAGE_TEST_MARKER();
1045                                                                 }
1046                                                         }
1047                                                         else
1048                                                         {
1049                                                                 mtCOVERAGE_TEST_MARKER();
1050                                                         }
1051                                                 }
1052                                                 else
1053                                                 {
1054                                                         mtCOVERAGE_TEST_MARKER();
1055                                                 }
1056                                         }
1057                                 }
1058                                 #else /* configUSE_QUEUE_SETS */
1059                                 {
1060                                         if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
1061                                         {
1062                                                 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
1063                                                 {
1064                                                         /* The task waiting has a higher priority so record that a
1065                                                         context switch is required. */
1066                                                         if( pxHigherPriorityTaskWoken != NULL )
1067                                                         {
1068                                                                 *pxHigherPriorityTaskWoken = pdTRUE;
1069                                                         }
1070                                                         else
1071                                                         {
1072                                                                 mtCOVERAGE_TEST_MARKER();
1073                                                         }
1074                                                 }
1075                                                 else
1076                                                 {
1077                                                         mtCOVERAGE_TEST_MARKER();
1078                                                 }
1079                                         }
1080                                         else
1081                                         {
1082                                                 mtCOVERAGE_TEST_MARKER();
1083                                         }
1084                                 }
1085                                 #endif /* configUSE_QUEUE_SETS */
1086                         }
1087                         else
1088                         {
1089                                 /* Increment the lock count so the task that unlocks the queue
1090                                 knows that data was posted while it was locked. */
1091                                 pxQueue->cTxLock = ( int8_t ) ( cTxLock + 1 );
1092                         }
1093
1094                         xReturn = pdPASS;
1095                 }
1096                 else
1097                 {
1098                         traceQUEUE_SEND_FROM_ISR_FAILED( pxQueue );
1099                         xReturn = errQUEUE_FULL;
1100                 }
1101         }
1102         portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
1103
1104         return xReturn;
1105 }
1106 /*-----------------------------------------------------------*/
1107
1108 BaseType_t xQueueGiveFromISR( QueueHandle_t xQueue, BaseType_t * const pxHigherPriorityTaskWoken )
1109 {
1110 BaseType_t xReturn;
1111 UBaseType_t uxSavedInterruptStatus;
1112 Queue_t * const pxQueue = xQueue;
1113
1114         /* Similar to xQueueGenericSendFromISR() but used with semaphores where the
1115         item size is 0.  Don't directly wake a task that was blocked on a queue
1116         read, instead return a flag to say whether a context switch is required or
1117         not (i.e. has a task with a higher priority than us been woken by this
1118         post). */
1119
1120         configASSERT( pxQueue );
1121
1122         /* xQueueGenericSendFromISR() should be used instead of xQueueGiveFromISR()
1123         if the item size is not 0. */
1124         configASSERT( pxQueue->uxItemSize == 0 );
1125
1126         /* Normally a mutex would not be given from an interrupt, especially if
1127         there is a mutex holder, as priority inheritance makes no sense for an
1128         interrupts, only tasks. */
1129         configASSERT( !( ( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX ) && ( pxQueue->u.xSemaphore.xMutexHolder != NULL ) ) );
1130
1131         /* RTOS ports that support interrupt nesting have the concept of a maximum
1132         system call (or maximum API call) interrupt priority.  Interrupts that are
1133         above the maximum system call priority are kept permanently enabled, even
1134         when the RTOS kernel is in a critical section, but cannot make any calls to
1135         FreeRTOS API functions.  If configASSERT() is defined in FreeRTOSConfig.h
1136         then portASSERT_IF_INTERRUPT_PRIORITY_INVALID() will result in an assertion
1137         failure if a FreeRTOS API function is called from an interrupt that has been
1138         assigned a priority above the configured maximum system call priority.
1139         Only FreeRTOS functions that end in FromISR can be called from interrupts
1140         that have been assigned a priority at or (logically) below the maximum
1141         system call     interrupt priority.  FreeRTOS maintains a separate interrupt
1142         safe API to ensure interrupt entry is as fast and as simple as possible.
1143         More information (albeit Cortex-M specific) is provided on the following
1144         link: http://www.freertos.org/RTOS-Cortex-M3-M4.html */
1145         portASSERT_IF_INTERRUPT_PRIORITY_INVALID();
1146
1147         uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
1148         {
1149                 const UBaseType_t uxMessagesWaiting = pxQueue->uxMessagesWaiting;
1150
1151                 /* When the queue is used to implement a semaphore no data is ever
1152                 moved through the queue but it is still valid to see if the queue 'has
1153                 space'. */
1154                 if( uxMessagesWaiting < pxQueue->uxLength )
1155                 {
1156                         const int8_t cTxLock = pxQueue->cTxLock;
1157
1158                         traceQUEUE_SEND_FROM_ISR( pxQueue );
1159
1160                         /* A task can only have an inherited priority if it is a mutex
1161                         holder - and if there is a mutex holder then the mutex cannot be
1162                         given from an ISR.  As this is the ISR version of the function it
1163                         can be assumed there is no mutex holder and no need to determine if
1164                         priority disinheritance is needed.  Simply increase the count of
1165                         messages (semaphores) available. */
1166                         pxQueue->uxMessagesWaiting = uxMessagesWaiting + ( UBaseType_t ) 1;
1167
1168                         /* The event list is not altered if the queue is locked.  This will
1169                         be done when the queue is unlocked later. */
1170                         if( cTxLock == queueUNLOCKED )
1171                         {
1172                                 #if ( configUSE_QUEUE_SETS == 1 )
1173                                 {
1174                                         if( pxQueue->pxQueueSetContainer != NULL )
1175                                         {
1176                                                 if( prvNotifyQueueSetContainer( pxQueue, queueSEND_TO_BACK ) != pdFALSE )
1177                                                 {
1178                                                         /* The semaphore is a member of a queue set, and
1179                                                         posting to the queue set caused a higher priority
1180                                                         task to unblock.  A context switch is required. */
1181                                                         if( pxHigherPriorityTaskWoken != NULL )
1182                                                         {
1183                                                                 *pxHigherPriorityTaskWoken = pdTRUE;
1184                                                         }
1185                                                         else
1186                                                         {
1187                                                                 mtCOVERAGE_TEST_MARKER();
1188                                                         }
1189                                                 }
1190                                                 else
1191                                                 {
1192                                                         mtCOVERAGE_TEST_MARKER();
1193                                                 }
1194                                         }
1195                                         else
1196                                         {
1197                                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
1198                                                 {
1199                                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
1200                                                         {
1201                                                                 /* The task waiting has a higher priority so
1202                                                                 record that a context switch is required. */
1203                                                                 if( pxHigherPriorityTaskWoken != NULL )
1204                                                                 {
1205                                                                         *pxHigherPriorityTaskWoken = pdTRUE;
1206                                                                 }
1207                                                                 else
1208                                                                 {
1209                                                                         mtCOVERAGE_TEST_MARKER();
1210                                                                 }
1211                                                         }
1212                                                         else
1213                                                         {
1214                                                                 mtCOVERAGE_TEST_MARKER();
1215                                                         }
1216                                                 }
1217                                                 else
1218                                                 {
1219                                                         mtCOVERAGE_TEST_MARKER();
1220                                                 }
1221                                         }
1222                                 }
1223                                 #else /* configUSE_QUEUE_SETS */
1224                                 {
1225                                         if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
1226                                         {
1227                                                 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
1228                                                 {
1229                                                         /* The task waiting has a higher priority so record that a
1230                                                         context switch is required. */
1231                                                         if( pxHigherPriorityTaskWoken != NULL )
1232                                                         {
1233                                                                 *pxHigherPriorityTaskWoken = pdTRUE;
1234                                                         }
1235                                                         else
1236                                                         {
1237                                                                 mtCOVERAGE_TEST_MARKER();
1238                                                         }
1239                                                 }
1240                                                 else
1241                                                 {
1242                                                         mtCOVERAGE_TEST_MARKER();
1243                                                 }
1244                                         }
1245                                         else
1246                                         {
1247                                                 mtCOVERAGE_TEST_MARKER();
1248                                         }
1249                                 }
1250                                 #endif /* configUSE_QUEUE_SETS */
1251                         }
1252                         else
1253                         {
1254                                 /* Increment the lock count so the task that unlocks the queue
1255                                 knows that data was posted while it was locked. */
1256                                 pxQueue->cTxLock = ( int8_t ) ( cTxLock + 1 );
1257                         }
1258
1259                         xReturn = pdPASS;
1260                 }
1261                 else
1262                 {
1263                         traceQUEUE_SEND_FROM_ISR_FAILED( pxQueue );
1264                         xReturn = errQUEUE_FULL;
1265                 }
1266         }
1267         portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
1268
1269         return xReturn;
1270 }
1271 /*-----------------------------------------------------------*/
1272
1273 BaseType_t xQueueReceive( QueueHandle_t xQueue, void * const pvBuffer, TickType_t xTicksToWait )
1274 {
1275 BaseType_t xEntryTimeSet = pdFALSE;
1276 TimeOut_t xTimeOut;
1277 Queue_t * const pxQueue = xQueue;
1278
1279         /* Check the pointer is not NULL. */
1280         configASSERT( ( pxQueue ) );
1281
1282         /* The buffer into which data is received can only be NULL if the data size
1283         is zero (so no data is copied into the buffer. */
1284         configASSERT( !( ( ( pvBuffer ) == NULL ) && ( ( pxQueue )->uxItemSize != ( UBaseType_t ) 0U ) ) );
1285
1286         /* Cannot block if the scheduler is suspended. */
1287         #if ( ( INCLUDE_xTaskGetSchedulerState == 1 ) || ( configUSE_TIMERS == 1 ) )
1288         {
1289                 configASSERT( !( ( xTaskGetSchedulerState() == taskSCHEDULER_SUSPENDED ) && ( xTicksToWait != 0 ) ) );
1290         }
1291         #endif
1292
1293
1294         /*lint -save -e904  This function relaxes the coding standard somewhat to
1295         allow return statements within the function itself.  This is done in the
1296         interest of execution time efficiency. */
1297         for( ;; )
1298         {
1299                 taskENTER_CRITICAL();
1300                 {
1301                         const UBaseType_t uxMessagesWaiting = pxQueue->uxMessagesWaiting;
1302
1303                         /* Is there data in the queue now?  To be running the calling task
1304                         must be the highest priority task wanting to access the queue. */
1305                         if( uxMessagesWaiting > ( UBaseType_t ) 0 )
1306                         {
1307                                 /* Data available, remove one item. */
1308                                 prvCopyDataFromQueue( pxQueue, pvBuffer );
1309                                 traceQUEUE_RECEIVE( pxQueue );
1310                                 pxQueue->uxMessagesWaiting = uxMessagesWaiting - ( UBaseType_t ) 1;
1311
1312                                 /* There is now space in the queue, were any tasks waiting to
1313                                 post to the queue?  If so, unblock the highest priority waiting
1314                                 task. */
1315                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
1316                                 {
1317                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
1318                                         {
1319                                                 queueYIELD_IF_USING_PREEMPTION();
1320                                         }
1321                                         else
1322                                         {
1323                                                 mtCOVERAGE_TEST_MARKER();
1324                                         }
1325                                 }
1326                                 else
1327                                 {
1328                                         mtCOVERAGE_TEST_MARKER();
1329                                 }
1330
1331                                 taskEXIT_CRITICAL();
1332                                 return pdPASS;
1333                         }
1334                         else
1335                         {
1336                                 if( xTicksToWait == ( TickType_t ) 0 )
1337                                 {
1338                                         /* The queue was empty and no block time is specified (or
1339                                         the block time has expired) so leave now. */
1340                                         taskEXIT_CRITICAL();
1341                                         traceQUEUE_RECEIVE_FAILED( pxQueue );
1342                                         return errQUEUE_EMPTY;
1343                                 }
1344                                 else if( xEntryTimeSet == pdFALSE )
1345                                 {
1346                                         /* The queue was empty and a block time was specified so
1347                                         configure the timeout structure. */
1348                                         vTaskInternalSetTimeOutState( &xTimeOut );
1349                                         xEntryTimeSet = pdTRUE;
1350                                 }
1351                                 else
1352                                 {
1353                                         /* Entry time was already set. */
1354                                         mtCOVERAGE_TEST_MARKER();
1355                                 }
1356                         }
1357                 }
1358                 taskEXIT_CRITICAL();
1359
1360                 /* Interrupts and other tasks can send to and receive from the queue
1361                 now the critical section has been exited. */
1362
1363                 vTaskSuspendAll();
1364                 prvLockQueue( pxQueue );
1365
1366                 /* Update the timeout state to see if it has expired yet. */
1367                 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
1368                 {
1369                         /* The timeout has not expired.  If the queue is still empty place
1370                         the task on the list of tasks waiting to receive from the queue. */
1371                         if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
1372                         {
1373                                 traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue );
1374                                 vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );
1375                                 prvUnlockQueue( pxQueue );
1376                                 if( xTaskResumeAll() == pdFALSE )
1377                                 {
1378                                         portYIELD_WITHIN_API();
1379                                 }
1380                                 else
1381                                 {
1382                                         mtCOVERAGE_TEST_MARKER();
1383                                 }
1384                         }
1385                         else
1386                         {
1387                                 /* The queue contains data again.  Loop back to try and read the
1388                                 data. */
1389                                 prvUnlockQueue( pxQueue );
1390                                 ( void ) xTaskResumeAll();
1391                         }
1392                 }
1393                 else
1394                 {
1395                         /* Timed out.  If there is no data in the queue exit, otherwise loop
1396                         back and attempt to read the data. */
1397                         prvUnlockQueue( pxQueue );
1398                         ( void ) xTaskResumeAll();
1399
1400                         if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
1401                         {
1402                                 traceQUEUE_RECEIVE_FAILED( pxQueue );
1403                                 return errQUEUE_EMPTY;
1404                         }
1405                         else
1406                         {
1407                                 mtCOVERAGE_TEST_MARKER();
1408                         }
1409                 }
1410         } /*lint -restore */
1411 }
1412 /*-----------------------------------------------------------*/
1413
1414 BaseType_t xQueueSemaphoreTake( QueueHandle_t xQueue, TickType_t xTicksToWait )
1415 {
1416 BaseType_t xEntryTimeSet = pdFALSE;
1417 TimeOut_t xTimeOut;
1418 Queue_t * const pxQueue = xQueue;
1419
1420 #if( configUSE_MUTEXES == 1 )
1421         BaseType_t xInheritanceOccurred = pdFALSE;
1422 #endif
1423
1424         /* Check the queue pointer is not NULL. */
1425         configASSERT( ( pxQueue ) );
1426
1427         /* Check this really is a semaphore, in which case the item size will be
1428         0. */
1429         configASSERT( pxQueue->uxItemSize == 0 );
1430
1431         /* Cannot block if the scheduler is suspended. */
1432         #if ( ( INCLUDE_xTaskGetSchedulerState == 1 ) || ( configUSE_TIMERS == 1 ) )
1433         {
1434                 configASSERT( !( ( xTaskGetSchedulerState() == taskSCHEDULER_SUSPENDED ) && ( xTicksToWait != 0 ) ) );
1435         }
1436         #endif
1437
1438
1439         /*lint -save -e904 This function relaxes the coding standard somewhat to allow return
1440         statements within the function itself.  This is done in the interest
1441         of execution time efficiency. */
1442         for( ;; )
1443         {
1444                 taskENTER_CRITICAL();
1445                 {
1446                         /* Semaphores are queues with an item size of 0, and where the
1447                         number of messages in the queue is the semaphore's count value. */
1448                         const UBaseType_t uxSemaphoreCount = pxQueue->uxMessagesWaiting;
1449
1450                         /* Is there data in the queue now?  To be running the calling task
1451                         must be the highest priority task wanting to access the queue. */
1452                         if( uxSemaphoreCount > ( UBaseType_t ) 0 )
1453                         {
1454                                 traceQUEUE_RECEIVE( pxQueue );
1455
1456                                 /* Semaphores are queues with a data size of zero and where the
1457                                 messages waiting is the semaphore's count.  Reduce the count. */
1458                                 pxQueue->uxMessagesWaiting = uxSemaphoreCount - ( UBaseType_t ) 1;
1459
1460                                 #if ( configUSE_MUTEXES == 1 )
1461                                 {
1462                                         if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
1463                                         {
1464                                                 /* Record the information required to implement
1465                                                 priority inheritance should it become necessary. */
1466                                                 pxQueue->u.xSemaphore.xMutexHolder = pvTaskIncrementMutexHeldCount();
1467                                         }
1468                                         else
1469                                         {
1470                                                 mtCOVERAGE_TEST_MARKER();
1471                                         }
1472                                 }
1473                                 #endif /* configUSE_MUTEXES */
1474
1475                                 /* Check to see if other tasks are blocked waiting to give the
1476                                 semaphore, and if so, unblock the highest priority such task. */
1477                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
1478                                 {
1479                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
1480                                         {
1481                                                 queueYIELD_IF_USING_PREEMPTION();
1482                                         }
1483                                         else
1484                                         {
1485                                                 mtCOVERAGE_TEST_MARKER();
1486                                         }
1487                                 }
1488                                 else
1489                                 {
1490                                         mtCOVERAGE_TEST_MARKER();
1491                                 }
1492
1493                                 taskEXIT_CRITICAL();
1494                                 return pdPASS;
1495                         }
1496                         else
1497                         {
1498                                 if( xTicksToWait == ( TickType_t ) 0 )
1499                                 {
1500                                         /* For inheritance to have occurred there must have been an
1501                                         initial timeout, and an adjusted timeout cannot become 0, as
1502                                         if it were 0 the function would have exited. */
1503                                         #if( configUSE_MUTEXES == 1 )
1504                                         {
1505                                                 configASSERT( xInheritanceOccurred == pdFALSE );
1506                                         }
1507                                         #endif /* configUSE_MUTEXES */
1508
1509                                         /* The semaphore count was 0 and no block time is specified
1510                                         (or the block time has expired) so exit now. */
1511                                         taskEXIT_CRITICAL();
1512                                         traceQUEUE_RECEIVE_FAILED( pxQueue );
1513                                         return errQUEUE_EMPTY;
1514                                 }
1515                                 else if( xEntryTimeSet == pdFALSE )
1516                                 {
1517                                         /* The semaphore count was 0 and a block time was specified
1518                                         so configure the timeout structure ready to block. */
1519                                         vTaskInternalSetTimeOutState( &xTimeOut );
1520                                         xEntryTimeSet = pdTRUE;
1521                                 }
1522                                 else
1523                                 {
1524                                         /* Entry time was already set. */
1525                                         mtCOVERAGE_TEST_MARKER();
1526                                 }
1527                         }
1528                 }
1529                 taskEXIT_CRITICAL();
1530
1531                 /* Interrupts and other tasks can give to and take from the semaphore
1532                 now the critical section has been exited. */
1533
1534                 vTaskSuspendAll();
1535                 prvLockQueue( pxQueue );
1536
1537                 /* Update the timeout state to see if it has expired yet. */
1538                 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
1539                 {
1540                         /* A block time is specified and not expired.  If the semaphore
1541                         count is 0 then enter the Blocked state to wait for a semaphore to
1542                         become available.  As semaphores are implemented with queues the
1543                         queue being empty is equivalent to the semaphore count being 0. */
1544                         if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
1545                         {
1546                                 traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue );
1547
1548                                 #if ( configUSE_MUTEXES == 1 )
1549                                 {
1550                                         if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
1551                                         {
1552                                                 taskENTER_CRITICAL();
1553                                                 {
1554                                                         xInheritanceOccurred = xTaskPriorityInherit( pxQueue->u.xSemaphore.xMutexHolder );
1555                                                 }
1556                                                 taskEXIT_CRITICAL();
1557                                         }
1558                                         else
1559                                         {
1560                                                 mtCOVERAGE_TEST_MARKER();
1561                                         }
1562                                 }
1563                                 #endif
1564
1565                                 vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );
1566                                 prvUnlockQueue( pxQueue );
1567                                 if( xTaskResumeAll() == pdFALSE )
1568                                 {
1569                                         portYIELD_WITHIN_API();
1570                                 }
1571                                 else
1572                                 {
1573                                         mtCOVERAGE_TEST_MARKER();
1574                                 }
1575                         }
1576                         else
1577                         {
1578                                 /* There was no timeout and the semaphore count was not 0, so
1579                                 attempt to take the semaphore again. */
1580                                 prvUnlockQueue( pxQueue );
1581                                 ( void ) xTaskResumeAll();
1582                         }
1583                 }
1584                 else
1585                 {
1586                         /* Timed out. */
1587                         prvUnlockQueue( pxQueue );
1588                         ( void ) xTaskResumeAll();
1589
1590                         /* If the semaphore count is 0 exit now as the timeout has
1591                         expired.  Otherwise return to attempt to take the semaphore that is
1592                         known to be available.  As semaphores are implemented by queues the
1593                         queue being empty is equivalent to the semaphore count being 0. */
1594                         if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
1595                         {
1596                                 #if ( configUSE_MUTEXES == 1 )
1597                                 {
1598                                         /* xInheritanceOccurred could only have be set if
1599                                         pxQueue->uxQueueType == queueQUEUE_IS_MUTEX so no need to
1600                                         test the mutex type again to check it is actually a mutex. */
1601                                         if( xInheritanceOccurred != pdFALSE )
1602                                         {
1603                                                 taskENTER_CRITICAL();
1604                                                 {
1605                                                         UBaseType_t uxHighestWaitingPriority;
1606
1607                                                         /* This task blocking on the mutex caused another
1608                                                         task to inherit this task's priority.  Now this task
1609                                                         has timed out the priority should be disinherited
1610                                                         again, but only as low as the next highest priority
1611                                                         task that is waiting for the same mutex. */
1612                                                         uxHighestWaitingPriority = prvGetDisinheritPriorityAfterTimeout( pxQueue );
1613                                                         vTaskPriorityDisinheritAfterTimeout( pxQueue->u.xSemaphore.xMutexHolder, uxHighestWaitingPriority );
1614                                                 }
1615                                                 taskEXIT_CRITICAL();
1616                                         }
1617                                 }
1618                                 #endif /* configUSE_MUTEXES */
1619
1620                                 traceQUEUE_RECEIVE_FAILED( pxQueue );
1621                                 return errQUEUE_EMPTY;
1622                         }
1623                         else
1624                         {
1625                                 mtCOVERAGE_TEST_MARKER();
1626                         }
1627                 }
1628         } /*lint -restore */
1629 }
1630 /*-----------------------------------------------------------*/
1631
1632 BaseType_t xQueuePeek( QueueHandle_t xQueue, void * const pvBuffer, TickType_t xTicksToWait )
1633 {
1634 BaseType_t xEntryTimeSet = pdFALSE;
1635 TimeOut_t xTimeOut;
1636 int8_t *pcOriginalReadPosition;
1637 Queue_t * const pxQueue = xQueue;
1638
1639         /* Check the pointer is not NULL. */
1640         configASSERT( ( pxQueue ) );
1641
1642         /* The buffer into which data is received can only be NULL if the data size
1643         is zero (so no data is copied into the buffer. */
1644         configASSERT( !( ( ( pvBuffer ) == NULL ) && ( ( pxQueue )->uxItemSize != ( UBaseType_t ) 0U ) ) );
1645
1646         /* Cannot block if the scheduler is suspended. */
1647         #if ( ( INCLUDE_xTaskGetSchedulerState == 1 ) || ( configUSE_TIMERS == 1 ) )
1648         {
1649                 configASSERT( !( ( xTaskGetSchedulerState() == taskSCHEDULER_SUSPENDED ) && ( xTicksToWait != 0 ) ) );
1650         }
1651         #endif
1652
1653
1654         /*lint -save -e904  This function relaxes the coding standard somewhat to
1655         allow return statements within the function itself.  This is done in the
1656         interest of execution time efficiency. */
1657         for( ;; )
1658         {
1659                 taskENTER_CRITICAL();
1660                 {
1661                         const UBaseType_t uxMessagesWaiting = pxQueue->uxMessagesWaiting;
1662
1663                         /* Is there data in the queue now?  To be running the calling task
1664                         must be the highest priority task wanting to access the queue. */
1665                         if( uxMessagesWaiting > ( UBaseType_t ) 0 )
1666                         {
1667                                 /* Remember the read position so it can be reset after the data
1668                                 is read from the queue as this function is only peeking the
1669                                 data, not removing it. */
1670                                 pcOriginalReadPosition = pxQueue->u.xQueue.pcReadFrom;
1671
1672                                 prvCopyDataFromQueue( pxQueue, pvBuffer );
1673                                 traceQUEUE_PEEK( pxQueue );
1674
1675                                 /* The data is not being removed, so reset the read pointer. */
1676                                 pxQueue->u.xQueue.pcReadFrom = pcOriginalReadPosition;
1677
1678                                 /* The data is being left in the queue, so see if there are
1679                                 any other tasks waiting for the data. */
1680                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
1681                                 {
1682                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
1683                                         {
1684                                                 /* The task waiting has a higher priority than this task. */
1685                                                 queueYIELD_IF_USING_PREEMPTION();
1686                                         }
1687                                         else
1688                                         {
1689                                                 mtCOVERAGE_TEST_MARKER();
1690                                         }
1691                                 }
1692                                 else
1693                                 {
1694                                         mtCOVERAGE_TEST_MARKER();
1695                                 }
1696
1697                                 taskEXIT_CRITICAL();
1698                                 return pdPASS;
1699                         }
1700                         else
1701                         {
1702                                 if( xTicksToWait == ( TickType_t ) 0 )
1703                                 {
1704                                         /* The queue was empty and no block time is specified (or
1705                                         the block time has expired) so leave now. */
1706                                         taskEXIT_CRITICAL();
1707                                         traceQUEUE_PEEK_FAILED( pxQueue );
1708                                         return errQUEUE_EMPTY;
1709                                 }
1710                                 else if( xEntryTimeSet == pdFALSE )
1711                                 {
1712                                         /* The queue was empty and a block time was specified so
1713                                         configure the timeout structure ready to enter the blocked
1714                                         state. */
1715                                         vTaskInternalSetTimeOutState( &xTimeOut );
1716                                         xEntryTimeSet = pdTRUE;
1717                                 }
1718                                 else
1719                                 {
1720                                         /* Entry time was already set. */
1721                                         mtCOVERAGE_TEST_MARKER();
1722                                 }
1723                         }
1724                 }
1725                 taskEXIT_CRITICAL();
1726
1727                 /* Interrupts and other tasks can send to and receive from the queue
1728                 now the critical section has been exited. */
1729
1730                 vTaskSuspendAll();
1731                 prvLockQueue( pxQueue );
1732
1733                 /* Update the timeout state to see if it has expired yet. */
1734                 if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
1735                 {
1736                         /* Timeout has not expired yet, check to see if there is data in the
1737                         queue now, and if not enter the Blocked state to wait for data. */
1738                         if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
1739                         {
1740                                 traceBLOCKING_ON_QUEUE_PEEK( pxQueue );
1741                                 vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );
1742                                 prvUnlockQueue( pxQueue );
1743                                 if( xTaskResumeAll() == pdFALSE )
1744                                 {
1745                                         portYIELD_WITHIN_API();
1746                                 }
1747                                 else
1748                                 {
1749                                         mtCOVERAGE_TEST_MARKER();
1750                                 }
1751                         }
1752                         else
1753                         {
1754                                 /* There is data in the queue now, so don't enter the blocked
1755                                 state, instead return to try and obtain the data. */
1756                                 prvUnlockQueue( pxQueue );
1757                                 ( void ) xTaskResumeAll();
1758                         }
1759                 }
1760                 else
1761                 {
1762                         /* The timeout has expired.  If there is still no data in the queue
1763                         exit, otherwise go back and try to read the data again. */
1764                         prvUnlockQueue( pxQueue );
1765                         ( void ) xTaskResumeAll();
1766
1767                         if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
1768                         {
1769                                 traceQUEUE_PEEK_FAILED( pxQueue );
1770                                 return errQUEUE_EMPTY;
1771                         }
1772                         else
1773                         {
1774                                 mtCOVERAGE_TEST_MARKER();
1775                         }
1776                 }
1777         } /*lint -restore */
1778 }
1779 /*-----------------------------------------------------------*/
1780
1781 BaseType_t xQueueReceiveFromISR( QueueHandle_t xQueue, void * const pvBuffer, BaseType_t * const pxHigherPriorityTaskWoken )
1782 {
1783 BaseType_t xReturn;
1784 UBaseType_t uxSavedInterruptStatus;
1785 Queue_t * const pxQueue = xQueue;
1786
1787         configASSERT( pxQueue );
1788         configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );
1789
1790         /* RTOS ports that support interrupt nesting have the concept of a maximum
1791         system call (or maximum API call) interrupt priority.  Interrupts that are
1792         above the maximum system call priority are kept permanently enabled, even
1793         when the RTOS kernel is in a critical section, but cannot make any calls to
1794         FreeRTOS API functions.  If configASSERT() is defined in FreeRTOSConfig.h
1795         then portASSERT_IF_INTERRUPT_PRIORITY_INVALID() will result in an assertion
1796         failure if a FreeRTOS API function is called from an interrupt that has been
1797         assigned a priority above the configured maximum system call priority.
1798         Only FreeRTOS functions that end in FromISR can be called from interrupts
1799         that have been assigned a priority at or (logically) below the maximum
1800         system call     interrupt priority.  FreeRTOS maintains a separate interrupt
1801         safe API to ensure interrupt entry is as fast and as simple as possible.
1802         More information (albeit Cortex-M specific) is provided on the following
1803         link: http://www.freertos.org/RTOS-Cortex-M3-M4.html */
1804         portASSERT_IF_INTERRUPT_PRIORITY_INVALID();
1805
1806         uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
1807         {
1808                 const UBaseType_t uxMessagesWaiting = pxQueue->uxMessagesWaiting;
1809
1810                 /* Cannot block in an ISR, so check there is data available. */
1811                 if( uxMessagesWaiting > ( UBaseType_t ) 0 )
1812                 {
1813                         const int8_t cRxLock = pxQueue->cRxLock;
1814
1815                         traceQUEUE_RECEIVE_FROM_ISR( pxQueue );
1816
1817                         prvCopyDataFromQueue( pxQueue, pvBuffer );
1818                         pxQueue->uxMessagesWaiting = uxMessagesWaiting - ( UBaseType_t ) 1;
1819
1820                         /* If the queue is locked the event list will not be modified.
1821                         Instead update the lock count so the task that unlocks the queue
1822                         will know that an ISR has removed data while the queue was
1823                         locked. */
1824                         if( cRxLock == queueUNLOCKED )
1825                         {
1826                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
1827                                 {
1828                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
1829                                         {
1830                                                 /* The task waiting has a higher priority than us so
1831                                                 force a context switch. */
1832                                                 if( pxHigherPriorityTaskWoken != NULL )
1833                                                 {
1834                                                         *pxHigherPriorityTaskWoken = pdTRUE;
1835                                                 }
1836                                                 else
1837                                                 {
1838                                                         mtCOVERAGE_TEST_MARKER();
1839                                                 }
1840                                         }
1841                                         else
1842                                         {
1843                                                 mtCOVERAGE_TEST_MARKER();
1844                                         }
1845                                 }
1846                                 else
1847                                 {
1848                                         mtCOVERAGE_TEST_MARKER();
1849                                 }
1850                         }
1851                         else
1852                         {
1853                                 /* Increment the lock count so the task that unlocks the queue
1854                                 knows that data was removed while it was locked. */
1855                                 pxQueue->cRxLock = ( int8_t ) ( cRxLock + 1 );
1856                         }
1857
1858                         xReturn = pdPASS;
1859                 }
1860                 else
1861                 {
1862                         xReturn = pdFAIL;
1863                         traceQUEUE_RECEIVE_FROM_ISR_FAILED( pxQueue );
1864                 }
1865         }
1866         portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
1867
1868         return xReturn;
1869 }
1870 /*-----------------------------------------------------------*/
1871
1872 BaseType_t xQueuePeekFromISR( QueueHandle_t xQueue,  void * const pvBuffer )
1873 {
1874 BaseType_t xReturn;
1875 UBaseType_t uxSavedInterruptStatus;
1876 int8_t *pcOriginalReadPosition;
1877 Queue_t * const pxQueue = xQueue;
1878
1879         configASSERT( pxQueue );
1880         configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );
1881         configASSERT( pxQueue->uxItemSize != 0 ); /* Can't peek a semaphore. */
1882
1883         /* RTOS ports that support interrupt nesting have the concept of a maximum
1884         system call (or maximum API call) interrupt priority.  Interrupts that are
1885         above the maximum system call priority are kept permanently enabled, even
1886         when the RTOS kernel is in a critical section, but cannot make any calls to
1887         FreeRTOS API functions.  If configASSERT() is defined in FreeRTOSConfig.h
1888         then portASSERT_IF_INTERRUPT_PRIORITY_INVALID() will result in an assertion
1889         failure if a FreeRTOS API function is called from an interrupt that has been
1890         assigned a priority above the configured maximum system call priority.
1891         Only FreeRTOS functions that end in FromISR can be called from interrupts
1892         that have been assigned a priority at or (logically) below the maximum
1893         system call     interrupt priority.  FreeRTOS maintains a separate interrupt
1894         safe API to ensure interrupt entry is as fast and as simple as possible.
1895         More information (albeit Cortex-M specific) is provided on the following
1896         link: http://www.freertos.org/RTOS-Cortex-M3-M4.html */
1897         portASSERT_IF_INTERRUPT_PRIORITY_INVALID();
1898
1899         uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
1900         {
1901                 /* Cannot block in an ISR, so check there is data available. */
1902                 if( pxQueue->uxMessagesWaiting > ( UBaseType_t ) 0 )
1903                 {
1904                         traceQUEUE_PEEK_FROM_ISR( pxQueue );
1905
1906                         /* Remember the read position so it can be reset as nothing is
1907                         actually being removed from the queue. */
1908                         pcOriginalReadPosition = pxQueue->u.xQueue.pcReadFrom;
1909                         prvCopyDataFromQueue( pxQueue, pvBuffer );
1910                         pxQueue->u.xQueue.pcReadFrom = pcOriginalReadPosition;
1911
1912                         xReturn = pdPASS;
1913                 }
1914                 else
1915                 {
1916                         xReturn = pdFAIL;
1917                         traceQUEUE_PEEK_FROM_ISR_FAILED( pxQueue );
1918                 }
1919         }
1920         portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
1921
1922         return xReturn;
1923 }
1924 /*-----------------------------------------------------------*/
1925
1926 UBaseType_t uxQueueMessagesWaiting( const QueueHandle_t xQueue )
1927 {
1928 UBaseType_t uxReturn;
1929
1930         configASSERT( xQueue );
1931
1932         taskENTER_CRITICAL();
1933         {
1934                 uxReturn = ( ( Queue_t * ) xQueue )->uxMessagesWaiting;
1935         }
1936         taskEXIT_CRITICAL();
1937
1938         return uxReturn;
1939 } /*lint !e818 Pointer cannot be declared const as xQueue is a typedef not pointer. */
1940 /*-----------------------------------------------------------*/
1941
1942 UBaseType_t uxQueueSpacesAvailable( const QueueHandle_t xQueue )
1943 {
1944 UBaseType_t uxReturn;
1945 Queue_t * const pxQueue = xQueue;
1946
1947         configASSERT( pxQueue );
1948
1949         taskENTER_CRITICAL();
1950         {
1951                 uxReturn = pxQueue->uxLength - pxQueue->uxMessagesWaiting;
1952         }
1953         taskEXIT_CRITICAL();
1954
1955         return uxReturn;
1956 } /*lint !e818 Pointer cannot be declared const as xQueue is a typedef not pointer. */
1957 /*-----------------------------------------------------------*/
1958
1959 UBaseType_t uxQueueMessagesWaitingFromISR( const QueueHandle_t xQueue )
1960 {
1961 UBaseType_t uxReturn;
1962 Queue_t * const pxQueue = xQueue;
1963
1964         configASSERT( pxQueue );
1965         uxReturn = pxQueue->uxMessagesWaiting;
1966
1967         return uxReturn;
1968 } /*lint !e818 Pointer cannot be declared const as xQueue is a typedef not pointer. */
1969 /*-----------------------------------------------------------*/
1970
1971 void vQueueDelete( QueueHandle_t xQueue )
1972 {
1973 Queue_t * const pxQueue = xQueue;
1974
1975         configASSERT( pxQueue );
1976         traceQUEUE_DELETE( pxQueue );
1977
1978         #if ( configQUEUE_REGISTRY_SIZE > 0 )
1979         {
1980                 vQueueUnregisterQueue( pxQueue );
1981         }
1982         #endif
1983
1984         #if( ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 0 ) )
1985         {
1986                 /* The queue can only have been allocated dynamically - free it
1987                 again. */
1988                 vPortFree( pxQueue );
1989         }
1990         #elif( ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 1 ) )
1991         {
1992                 /* The queue could have been allocated statically or dynamically, so
1993                 check before attempting to free the memory. */
1994                 if( pxQueue->ucStaticallyAllocated == ( uint8_t ) pdFALSE )
1995                 {
1996                         vPortFree( pxQueue );
1997                 }
1998                 else
1999                 {
2000                         mtCOVERAGE_TEST_MARKER();
2001                 }
2002         }
2003         #else
2004         {
2005                 /* The queue must have been statically allocated, so is not going to be
2006                 deleted.  Avoid compiler warnings about the unused parameter. */
2007                 ( void ) pxQueue;
2008         }
2009         #endif /* configSUPPORT_DYNAMIC_ALLOCATION */
2010 }
2011 /*-----------------------------------------------------------*/
2012
2013 #if ( configUSE_TRACE_FACILITY == 1 )
2014
2015         UBaseType_t uxQueueGetQueueNumber( QueueHandle_t xQueue )
2016         {
2017                 return ( ( Queue_t * ) xQueue )->uxQueueNumber;
2018         }
2019
2020 #endif /* configUSE_TRACE_FACILITY */
2021 /*-----------------------------------------------------------*/
2022
2023 #if ( configUSE_TRACE_FACILITY == 1 )
2024
2025         void vQueueSetQueueNumber( QueueHandle_t xQueue, UBaseType_t uxQueueNumber )
2026         {
2027                 ( ( Queue_t * ) xQueue )->uxQueueNumber = uxQueueNumber;
2028         }
2029
2030 #endif /* configUSE_TRACE_FACILITY */
2031 /*-----------------------------------------------------------*/
2032
2033 #if ( configUSE_TRACE_FACILITY == 1 )
2034
2035         uint8_t ucQueueGetQueueType( QueueHandle_t xQueue )
2036         {
2037                 return ( ( Queue_t * ) xQueue )->ucQueueType;
2038         }
2039
2040 #endif /* configUSE_TRACE_FACILITY */
2041 /*-----------------------------------------------------------*/
2042
2043 #if( configUSE_MUTEXES == 1 )
2044
2045         static UBaseType_t prvGetDisinheritPriorityAfterTimeout( const Queue_t * const pxQueue )
2046         {
2047         UBaseType_t uxHighestPriorityOfWaitingTasks;
2048
2049                 /* If a task waiting for a mutex causes the mutex holder to inherit a
2050                 priority, but the waiting task times out, then the holder should
2051                 disinherit the priority - but only down to the highest priority of any
2052                 other tasks that are waiting for the same mutex.  For this purpose,
2053                 return the priority of the highest priority task that is waiting for the
2054                 mutex. */
2055                 if( listCURRENT_LIST_LENGTH( &( pxQueue->xTasksWaitingToReceive ) ) > 0U )
2056                 {
2057                         uxHighestPriorityOfWaitingTasks = ( UBaseType_t ) configMAX_PRIORITIES - ( UBaseType_t ) listGET_ITEM_VALUE_OF_HEAD_ENTRY( &( pxQueue->xTasksWaitingToReceive ) );
2058                 }
2059                 else
2060                 {
2061                         uxHighestPriorityOfWaitingTasks = tskIDLE_PRIORITY;
2062                 }
2063
2064                 return uxHighestPriorityOfWaitingTasks;
2065         }
2066
2067 #endif /* configUSE_MUTEXES */
2068 /*-----------------------------------------------------------*/
2069
2070 static BaseType_t prvCopyDataToQueue( Queue_t * const pxQueue, const void *pvItemToQueue, const BaseType_t xPosition )
2071 {
2072 BaseType_t xReturn = pdFALSE;
2073 UBaseType_t uxMessagesWaiting;
2074
2075         /* This function is called from a critical section. */
2076
2077         uxMessagesWaiting = pxQueue->uxMessagesWaiting;
2078
2079         if( pxQueue->uxItemSize == ( UBaseType_t ) 0 )
2080         {
2081                 #if ( configUSE_MUTEXES == 1 )
2082                 {
2083                         if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
2084                         {
2085                                 /* The mutex is no longer being held. */
2086                                 xReturn = xTaskPriorityDisinherit( pxQueue->u.xSemaphore.xMutexHolder );
2087                                 pxQueue->u.xSemaphore.xMutexHolder = NULL;
2088                         }
2089                         else
2090                         {
2091                                 mtCOVERAGE_TEST_MARKER();
2092                         }
2093                 }
2094                 #endif /* configUSE_MUTEXES */
2095         }
2096         else if( xPosition == queueSEND_TO_BACK )
2097         {
2098                 ( 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. */
2099                 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. */
2100                 if( pxQueue->pcWriteTo >= pxQueue->u.xQueue.pcTail ) /*lint !e946 MISRA exception justified as comparison of pointers is the cleanest solution. */
2101                 {
2102                         pxQueue->pcWriteTo = pxQueue->pcHead;
2103                 }
2104                 else
2105                 {
2106                         mtCOVERAGE_TEST_MARKER();
2107                 }
2108         }
2109         else
2110         {
2111                 ( 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. */
2112                 pxQueue->u.xQueue.pcReadFrom -= pxQueue->uxItemSize;
2113                 if( pxQueue->u.xQueue.pcReadFrom < pxQueue->pcHead ) /*lint !e946 MISRA exception justified as comparison of pointers is the cleanest solution. */
2114                 {
2115                         pxQueue->u.xQueue.pcReadFrom = ( pxQueue->u.xQueue.pcTail - pxQueue->uxItemSize );
2116                 }
2117                 else
2118                 {
2119                         mtCOVERAGE_TEST_MARKER();
2120                 }
2121
2122                 if( xPosition == queueOVERWRITE )
2123                 {
2124                         if( uxMessagesWaiting > ( UBaseType_t ) 0 )
2125                         {
2126                                 /* An item is not being added but overwritten, so subtract
2127                                 one from the recorded number of items in the queue so when
2128                                 one is added again below the number of recorded items remains
2129                                 correct. */
2130                                 --uxMessagesWaiting;
2131                         }
2132                         else
2133                         {
2134                                 mtCOVERAGE_TEST_MARKER();
2135                         }
2136                 }
2137                 else
2138                 {
2139                         mtCOVERAGE_TEST_MARKER();
2140                 }
2141         }
2142
2143         pxQueue->uxMessagesWaiting = uxMessagesWaiting + ( UBaseType_t ) 1;
2144
2145         return xReturn;
2146 }
2147 /*-----------------------------------------------------------*/
2148
2149 static void prvCopyDataFromQueue( Queue_t * const pxQueue, void * const pvBuffer )
2150 {
2151         if( pxQueue->uxItemSize != ( UBaseType_t ) 0 )
2152         {
2153                 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. */
2154                 if( pxQueue->u.xQueue.pcReadFrom >= pxQueue->u.xQueue.pcTail ) /*lint !e946 MISRA exception justified as use of the relational operator is the cleanest solutions. */
2155                 {
2156                         pxQueue->u.xQueue.pcReadFrom = pxQueue->pcHead;
2157                 }
2158                 else
2159                 {
2160                         mtCOVERAGE_TEST_MARKER();
2161                 }
2162                 ( 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. */
2163         }
2164 }
2165 /*-----------------------------------------------------------*/
2166
2167 static void prvUnlockQueue( Queue_t * const pxQueue )
2168 {
2169         /* THIS FUNCTION MUST BE CALLED WITH THE SCHEDULER SUSPENDED. */
2170
2171         /* The lock counts contains the number of extra data items placed or
2172         removed from the queue while the queue was locked.  When a queue is
2173         locked items can be added or removed, but the event lists cannot be
2174         updated. */
2175         taskENTER_CRITICAL();
2176         {
2177                 int8_t cTxLock = pxQueue->cTxLock;
2178
2179                 /* See if data was added to the queue while it was locked. */
2180                 while( cTxLock > queueLOCKED_UNMODIFIED )
2181                 {
2182                         /* Data was posted while the queue was locked.  Are any tasks
2183                         blocked waiting for data to become available? */
2184                         #if ( configUSE_QUEUE_SETS == 1 )
2185                         {
2186                                 if( pxQueue->pxQueueSetContainer != NULL )
2187                                 {
2188                                         if( prvNotifyQueueSetContainer( pxQueue, queueSEND_TO_BACK ) != pdFALSE )
2189                                         {
2190                                                 /* The queue is a member of a queue set, and posting to
2191                                                 the queue set caused a higher priority task to unblock.
2192                                                 A context switch is required. */
2193                                                 vTaskMissedYield();
2194                                         }
2195                                         else
2196                                         {
2197                                                 mtCOVERAGE_TEST_MARKER();
2198                                         }
2199                                 }
2200                                 else
2201                                 {
2202                                         /* Tasks that are removed from the event list will get
2203                                         added to the pending ready list as the scheduler is still
2204                                         suspended. */
2205                                         if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
2206                                         {
2207                                                 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
2208                                                 {
2209                                                         /* The task waiting has a higher priority so record that a
2210                                                         context switch is required. */
2211                                                         vTaskMissedYield();
2212                                                 }
2213                                                 else
2214                                                 {
2215                                                         mtCOVERAGE_TEST_MARKER();
2216                                                 }
2217                                         }
2218                                         else
2219                                         {
2220                                                 break;
2221                                         }
2222                                 }
2223                         }
2224                         #else /* configUSE_QUEUE_SETS */
2225                         {
2226                                 /* Tasks that are removed from the event list will get added to
2227                                 the pending ready list as the scheduler is still suspended. */
2228                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
2229                                 {
2230                                         if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
2231                                         {
2232                                                 /* The task waiting has a higher priority so record that
2233                                                 a context switch is required. */
2234                                                 vTaskMissedYield();
2235                                         }
2236                                         else
2237                                         {
2238                                                 mtCOVERAGE_TEST_MARKER();
2239                                         }
2240                                 }
2241                                 else
2242                                 {
2243                                         break;
2244                                 }
2245                         }
2246                         #endif /* configUSE_QUEUE_SETS */
2247
2248                         --cTxLock;
2249                 }
2250
2251                 pxQueue->cTxLock = queueUNLOCKED;
2252         }
2253         taskEXIT_CRITICAL();
2254
2255         /* Do the same for the Rx lock. */
2256         taskENTER_CRITICAL();
2257         {
2258                 int8_t cRxLock = pxQueue->cRxLock;
2259
2260                 while( cRxLock > queueLOCKED_UNMODIFIED )
2261                 {
2262                         if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
2263                         {
2264                                 if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
2265                                 {
2266                                         vTaskMissedYield();
2267                                 }
2268                                 else
2269                                 {
2270                                         mtCOVERAGE_TEST_MARKER();
2271                                 }
2272
2273                                 --cRxLock;
2274                         }
2275                         else
2276                         {
2277                                 break;
2278                         }
2279                 }
2280
2281                 pxQueue->cRxLock = queueUNLOCKED;
2282         }
2283         taskEXIT_CRITICAL();
2284 }
2285 /*-----------------------------------------------------------*/
2286
2287 static BaseType_t prvIsQueueEmpty( const Queue_t *pxQueue )
2288 {
2289 BaseType_t xReturn;
2290
2291         taskENTER_CRITICAL();
2292         {
2293                 if( pxQueue->uxMessagesWaiting == ( UBaseType_t )  0 )
2294                 {
2295                         xReturn = pdTRUE;
2296                 }
2297                 else
2298                 {
2299                         xReturn = pdFALSE;
2300                 }
2301         }
2302         taskEXIT_CRITICAL();
2303
2304         return xReturn;
2305 }
2306 /*-----------------------------------------------------------*/
2307
2308 BaseType_t xQueueIsQueueEmptyFromISR( const QueueHandle_t xQueue )
2309 {
2310 BaseType_t xReturn;
2311 Queue_t * const pxQueue = xQueue;
2312
2313         configASSERT( pxQueue );
2314         if( pxQueue->uxMessagesWaiting == ( UBaseType_t ) 0 )
2315         {
2316                 xReturn = pdTRUE;
2317         }
2318         else
2319         {
2320                 xReturn = pdFALSE;
2321         }
2322
2323         return xReturn;
2324 } /*lint !e818 xQueue could not be pointer to const because it is a typedef. */
2325 /*-----------------------------------------------------------*/
2326
2327 static BaseType_t prvIsQueueFull( const Queue_t *pxQueue )
2328 {
2329 BaseType_t xReturn;
2330
2331         taskENTER_CRITICAL();
2332         {
2333                 if( pxQueue->uxMessagesWaiting == pxQueue->uxLength )
2334                 {
2335                         xReturn = pdTRUE;
2336                 }
2337                 else
2338                 {
2339                         xReturn = pdFALSE;
2340                 }
2341         }
2342         taskEXIT_CRITICAL();
2343
2344         return xReturn;
2345 }
2346 /*-----------------------------------------------------------*/
2347
2348 BaseType_t xQueueIsQueueFullFromISR( const QueueHandle_t xQueue )
2349 {
2350 BaseType_t xReturn;
2351 Queue_t * const pxQueue = xQueue;
2352
2353         configASSERT( pxQueue );
2354         if( pxQueue->uxMessagesWaiting == pxQueue->uxLength )
2355         {
2356                 xReturn = pdTRUE;
2357         }
2358         else
2359         {
2360                 xReturn = pdFALSE;
2361         }
2362
2363         return xReturn;
2364 } /*lint !e818 xQueue could not be pointer to const because it is a typedef. */
2365 /*-----------------------------------------------------------*/
2366
2367 #if ( configUSE_CO_ROUTINES == 1 )
2368
2369         BaseType_t xQueueCRSend( QueueHandle_t xQueue, const void *pvItemToQueue, TickType_t xTicksToWait )
2370         {
2371         BaseType_t xReturn;
2372         Queue_t * const pxQueue = xQueue;
2373
2374                 /* If the queue is already full we may have to block.  A critical section
2375                 is required to prevent an interrupt removing something from the queue
2376                 between the check to see if the queue is full and blocking on the queue. */
2377                 portDISABLE_INTERRUPTS();
2378                 {
2379                         if( prvIsQueueFull( pxQueue ) != pdFALSE )
2380                         {
2381                                 /* The queue is full - do we want to block or just leave without
2382                                 posting? */
2383                                 if( xTicksToWait > ( TickType_t ) 0 )
2384                                 {
2385                                         /* As this is called from a coroutine we cannot block directly, but
2386                                         return indicating that we need to block. */
2387                                         vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToSend ) );
2388                                         portENABLE_INTERRUPTS();
2389                                         return errQUEUE_BLOCKED;
2390                                 }
2391                                 else
2392                                 {
2393                                         portENABLE_INTERRUPTS();
2394                                         return errQUEUE_FULL;
2395                                 }
2396                         }
2397                 }
2398                 portENABLE_INTERRUPTS();
2399
2400                 portDISABLE_INTERRUPTS();
2401                 {
2402                         if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
2403                         {
2404                                 /* There is room in the queue, copy the data into the queue. */
2405                                 prvCopyDataToQueue( pxQueue, pvItemToQueue, queueSEND_TO_BACK );
2406                                 xReturn = pdPASS;
2407
2408                                 /* Were any co-routines waiting for data to become available? */
2409                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
2410                                 {
2411                                         /* In this instance the co-routine could be placed directly
2412                                         into the ready list as we are within a critical section.
2413                                         Instead the same pending ready list mechanism is used as if
2414                                         the event were caused from within an interrupt. */
2415                                         if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
2416                                         {
2417                                                 /* The co-routine waiting has a higher priority so record
2418                                                 that a yield might be appropriate. */
2419                                                 xReturn = errQUEUE_YIELD;
2420                                         }
2421                                         else
2422                                         {
2423                                                 mtCOVERAGE_TEST_MARKER();
2424                                         }
2425                                 }
2426                                 else
2427                                 {
2428                                         mtCOVERAGE_TEST_MARKER();
2429                                 }
2430                         }
2431                         else
2432                         {
2433                                 xReturn = errQUEUE_FULL;
2434                         }
2435                 }
2436                 portENABLE_INTERRUPTS();
2437
2438                 return xReturn;
2439         }
2440
2441 #endif /* configUSE_CO_ROUTINES */
2442 /*-----------------------------------------------------------*/
2443
2444 #if ( configUSE_CO_ROUTINES == 1 )
2445
2446         BaseType_t xQueueCRReceive( QueueHandle_t xQueue, void *pvBuffer, TickType_t xTicksToWait )
2447         {
2448         BaseType_t xReturn;
2449         Queue_t * const pxQueue = xQueue;
2450
2451                 /* If the queue is already empty we may have to block.  A critical section
2452                 is required to prevent an interrupt adding something to the queue
2453                 between the check to see if the queue is empty and blocking on the queue. */
2454                 portDISABLE_INTERRUPTS();
2455                 {
2456                         if( pxQueue->uxMessagesWaiting == ( UBaseType_t ) 0 )
2457                         {
2458                                 /* There are no messages in the queue, do we want to block or just
2459                                 leave with nothing? */
2460                                 if( xTicksToWait > ( TickType_t ) 0 )
2461                                 {
2462                                         /* As this is a co-routine we cannot block directly, but return
2463                                         indicating that we need to block. */
2464                                         vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToReceive ) );
2465                                         portENABLE_INTERRUPTS();
2466                                         return errQUEUE_BLOCKED;
2467                                 }
2468                                 else
2469                                 {
2470                                         portENABLE_INTERRUPTS();
2471                                         return errQUEUE_FULL;
2472                                 }
2473                         }
2474                         else
2475                         {
2476                                 mtCOVERAGE_TEST_MARKER();
2477                         }
2478                 }
2479                 portENABLE_INTERRUPTS();
2480
2481                 portDISABLE_INTERRUPTS();
2482                 {
2483                         if( pxQueue->uxMessagesWaiting > ( UBaseType_t ) 0 )
2484                         {
2485                                 /* Data is available from the queue. */
2486                                 pxQueue->u.xQueue.pcReadFrom += pxQueue->uxItemSize;
2487                                 if( pxQueue->u.xQueue.pcReadFrom >= pxQueue->u.xQueue.pcTail )
2488                                 {
2489                                         pxQueue->u.xQueue.pcReadFrom = pxQueue->pcHead;
2490                                 }
2491                                 else
2492                                 {
2493                                         mtCOVERAGE_TEST_MARKER();
2494                                 }
2495                                 --( pxQueue->uxMessagesWaiting );
2496                                 ( void ) memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->u.xQueue.pcReadFrom, ( unsigned ) pxQueue->uxItemSize );
2497
2498                                 xReturn = pdPASS;
2499
2500                                 /* Were any co-routines waiting for space to become available? */
2501                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
2502                                 {
2503                                         /* In this instance the co-routine could be placed directly
2504                                         into the ready list as we are within a critical section.
2505                                         Instead the same pending ready list mechanism is used as if
2506                                         the event were caused from within an interrupt. */
2507                                         if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
2508                                         {
2509                                                 xReturn = errQUEUE_YIELD;
2510                                         }
2511                                         else
2512                                         {
2513                                                 mtCOVERAGE_TEST_MARKER();
2514                                         }
2515                                 }
2516                                 else
2517                                 {
2518                                         mtCOVERAGE_TEST_MARKER();
2519                                 }
2520                         }
2521                         else
2522                         {
2523                                 xReturn = pdFAIL;
2524                         }
2525                 }
2526                 portENABLE_INTERRUPTS();
2527
2528                 return xReturn;
2529         }
2530
2531 #endif /* configUSE_CO_ROUTINES */
2532 /*-----------------------------------------------------------*/
2533
2534 #if ( configUSE_CO_ROUTINES == 1 )
2535
2536         BaseType_t xQueueCRSendFromISR( QueueHandle_t xQueue, const void *pvItemToQueue, BaseType_t xCoRoutinePreviouslyWoken )
2537         {
2538         Queue_t * const pxQueue = xQueue;
2539
2540                 /* Cannot block within an ISR so if there is no space on the queue then
2541                 exit without doing anything. */
2542                 if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
2543                 {
2544                         prvCopyDataToQueue( pxQueue, pvItemToQueue, queueSEND_TO_BACK );
2545
2546                         /* We only want to wake one co-routine per ISR, so check that a
2547                         co-routine has not already been woken. */
2548                         if( xCoRoutinePreviouslyWoken == pdFALSE )
2549                         {
2550                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
2551                                 {
2552                                         if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
2553                                         {
2554                                                 return pdTRUE;
2555                                         }
2556                                         else
2557                                         {
2558                                                 mtCOVERAGE_TEST_MARKER();
2559                                         }
2560                                 }
2561                                 else
2562                                 {
2563                                         mtCOVERAGE_TEST_MARKER();
2564                                 }
2565                         }
2566                         else
2567                         {
2568                                 mtCOVERAGE_TEST_MARKER();
2569                         }
2570                 }
2571                 else
2572                 {
2573                         mtCOVERAGE_TEST_MARKER();
2574                 }
2575
2576                 return xCoRoutinePreviouslyWoken;
2577         }
2578
2579 #endif /* configUSE_CO_ROUTINES */
2580 /*-----------------------------------------------------------*/
2581
2582 #if ( configUSE_CO_ROUTINES == 1 )
2583
2584         BaseType_t xQueueCRReceiveFromISR( QueueHandle_t xQueue, void *pvBuffer, BaseType_t *pxCoRoutineWoken )
2585         {
2586         BaseType_t xReturn;
2587         Queue_t * const pxQueue = xQueue;
2588
2589                 /* We cannot block from an ISR, so check there is data available. If
2590                 not then just leave without doing anything. */
2591                 if( pxQueue->uxMessagesWaiting > ( UBaseType_t ) 0 )
2592                 {
2593                         /* Copy the data from the queue. */
2594                         pxQueue->u.xQueue.pcReadFrom += pxQueue->uxItemSize;
2595                         if( pxQueue->u.xQueue.pcReadFrom >= pxQueue->u.xQueue.pcTail )
2596                         {
2597                                 pxQueue->u.xQueue.pcReadFrom = pxQueue->pcHead;
2598                         }
2599                         else
2600                         {
2601                                 mtCOVERAGE_TEST_MARKER();
2602                         }
2603                         --( pxQueue->uxMessagesWaiting );
2604                         ( void ) memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->u.xQueue.pcReadFrom, ( unsigned ) pxQueue->uxItemSize );
2605
2606                         if( ( *pxCoRoutineWoken ) == pdFALSE )
2607                         {
2608                                 if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
2609                                 {
2610                                         if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
2611                                         {
2612                                                 *pxCoRoutineWoken = pdTRUE;
2613                                         }
2614                                         else
2615                                         {
2616                                                 mtCOVERAGE_TEST_MARKER();
2617                                         }
2618                                 }
2619                                 else
2620                                 {
2621                                         mtCOVERAGE_TEST_MARKER();
2622                                 }
2623                         }
2624                         else
2625                         {
2626                                 mtCOVERAGE_TEST_MARKER();
2627                         }
2628
2629                         xReturn = pdPASS;
2630                 }
2631                 else
2632                 {
2633                         xReturn = pdFAIL;
2634                 }
2635
2636                 return xReturn;
2637         }
2638
2639 #endif /* configUSE_CO_ROUTINES */
2640 /*-----------------------------------------------------------*/
2641
2642 #if ( configQUEUE_REGISTRY_SIZE > 0 )
2643
2644         void vQueueAddToRegistry( QueueHandle_t xQueue, const char *pcQueueName ) /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
2645         {
2646         UBaseType_t ux;
2647
2648                 /* See if there is an empty space in the registry.  A NULL name denotes
2649                 a free slot. */
2650                 for( ux = ( UBaseType_t ) 0U; ux < ( UBaseType_t ) configQUEUE_REGISTRY_SIZE; ux++ )
2651                 {
2652                         if( xQueueRegistry[ ux ].pcQueueName == NULL )
2653                         {
2654                                 /* Store the information on this queue. */
2655                                 xQueueRegistry[ ux ].pcQueueName = pcQueueName;
2656                                 xQueueRegistry[ ux ].xHandle = xQueue;
2657
2658                                 traceQUEUE_REGISTRY_ADD( xQueue, pcQueueName );
2659                                 break;
2660                         }
2661                         else
2662                         {
2663                                 mtCOVERAGE_TEST_MARKER();
2664                         }
2665                 }
2666         }
2667
2668 #endif /* configQUEUE_REGISTRY_SIZE */
2669 /*-----------------------------------------------------------*/
2670
2671 #if ( configQUEUE_REGISTRY_SIZE > 0 )
2672
2673         const char *pcQueueGetName( QueueHandle_t xQueue ) /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
2674         {
2675         UBaseType_t ux;
2676         const char *pcReturn = NULL; /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
2677
2678                 /* Note there is nothing here to protect against another task adding or
2679                 removing entries from the registry while it is being searched. */
2680                 for( ux = ( UBaseType_t ) 0U; ux < ( UBaseType_t ) configQUEUE_REGISTRY_SIZE; ux++ )
2681                 {
2682                         if( xQueueRegistry[ ux ].xHandle == xQueue )
2683                         {
2684                                 pcReturn = xQueueRegistry[ ux ].pcQueueName;
2685                                 break;
2686                         }
2687                         else
2688                         {
2689                                 mtCOVERAGE_TEST_MARKER();
2690                         }
2691                 }
2692
2693                 return pcReturn;
2694         } /*lint !e818 xQueue cannot be a pointer to const because it is a typedef. */
2695
2696 #endif /* configQUEUE_REGISTRY_SIZE */
2697 /*-----------------------------------------------------------*/
2698
2699 #if ( configQUEUE_REGISTRY_SIZE > 0 )
2700
2701         void vQueueUnregisterQueue( QueueHandle_t xQueue )
2702         {
2703         UBaseType_t ux;
2704
2705                 /* See if the handle of the queue being unregistered in actually in the
2706                 registry. */
2707                 for( ux = ( UBaseType_t ) 0U; ux < ( UBaseType_t ) configQUEUE_REGISTRY_SIZE; ux++ )
2708                 {
2709                         if( xQueueRegistry[ ux ].xHandle == xQueue )
2710                         {
2711                                 /* Set the name to NULL to show that this slot if free again. */
2712                                 xQueueRegistry[ ux ].pcQueueName = NULL;
2713
2714                                 /* Set the handle to NULL to ensure the same queue handle cannot
2715                                 appear in the registry twice if it is added, removed, then
2716                                 added again. */
2717                                 xQueueRegistry[ ux ].xHandle = ( QueueHandle_t ) 0;
2718                                 break;
2719                         }
2720                         else
2721                         {
2722                                 mtCOVERAGE_TEST_MARKER();
2723                         }
2724                 }
2725
2726         } /*lint !e818 xQueue could not be pointer to const because it is a typedef. */
2727
2728 #endif /* configQUEUE_REGISTRY_SIZE */
2729 /*-----------------------------------------------------------*/
2730
2731 #if ( configUSE_TIMERS == 1 )
2732
2733         void vQueueWaitForMessageRestricted( QueueHandle_t xQueue, TickType_t xTicksToWait, const BaseType_t xWaitIndefinitely )
2734         {
2735         Queue_t * const pxQueue = xQueue;
2736
2737                 /* This function should not be called by application code hence the
2738                 'Restricted' in its name.  It is not part of the public API.  It is
2739                 designed for use by kernel code, and has special calling requirements.
2740                 It can result in vListInsert() being called on a list that can only
2741                 possibly ever have one item in it, so the list will be fast, but even
2742                 so it should be called with the scheduler locked and not from a critical
2743                 section. */
2744
2745                 /* Only do anything if there are no messages in the queue.  This function
2746                 will not actually cause the task to block, just place it on a blocked
2747                 list.  It will not block until the scheduler is unlocked - at which
2748                 time a yield will be performed.  If an item is added to the queue while
2749                 the queue is locked, and the calling task blocks on the queue, then the
2750                 calling task will be immediately unblocked when the queue is unlocked. */
2751                 prvLockQueue( pxQueue );
2752                 if( pxQueue->uxMessagesWaiting == ( UBaseType_t ) 0U )
2753                 {
2754                         /* There is nothing in the queue, block for the specified period. */
2755                         vTaskPlaceOnEventListRestricted( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait, xWaitIndefinitely );
2756                 }
2757                 else
2758                 {
2759                         mtCOVERAGE_TEST_MARKER();
2760                 }
2761                 prvUnlockQueue( pxQueue );
2762         }
2763
2764 #endif /* configUSE_TIMERS */
2765 /*-----------------------------------------------------------*/
2766
2767 #if( ( configUSE_QUEUE_SETS == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )
2768
2769         QueueSetHandle_t xQueueCreateSet( const UBaseType_t uxEventQueueLength )
2770         {
2771         QueueSetHandle_t pxQueue;
2772
2773                 pxQueue = xQueueGenericCreate( uxEventQueueLength, ( UBaseType_t ) sizeof( Queue_t * ), queueQUEUE_TYPE_SET );
2774
2775                 return pxQueue;
2776         }
2777
2778 #endif /* configUSE_QUEUE_SETS */
2779 /*-----------------------------------------------------------*/
2780
2781 #if ( configUSE_QUEUE_SETS == 1 )
2782
2783         BaseType_t xQueueAddToSet( QueueSetMemberHandle_t xQueueOrSemaphore, QueueSetHandle_t xQueueSet )
2784         {
2785         BaseType_t xReturn;
2786
2787                 taskENTER_CRITICAL();
2788                 {
2789                         if( ( ( Queue_t * ) xQueueOrSemaphore )->pxQueueSetContainer != NULL )
2790                         {
2791                                 /* Cannot add a queue/semaphore to more than one queue set. */
2792                                 xReturn = pdFAIL;
2793                         }
2794                         else if( ( ( Queue_t * ) xQueueOrSemaphore )->uxMessagesWaiting != ( UBaseType_t ) 0 )
2795                         {
2796                                 /* Cannot add a queue/semaphore to a queue set if there are already
2797                                 items in the queue/semaphore. */
2798                                 xReturn = pdFAIL;
2799                         }
2800                         else
2801                         {
2802                                 ( ( Queue_t * ) xQueueOrSemaphore )->pxQueueSetContainer = xQueueSet;
2803                                 xReturn = pdPASS;
2804                         }
2805                 }
2806                 taskEXIT_CRITICAL();
2807
2808                 return xReturn;
2809         }
2810
2811 #endif /* configUSE_QUEUE_SETS */
2812 /*-----------------------------------------------------------*/
2813
2814 #if ( configUSE_QUEUE_SETS == 1 )
2815
2816         BaseType_t xQueueRemoveFromSet( QueueSetMemberHandle_t xQueueOrSemaphore, QueueSetHandle_t xQueueSet )
2817         {
2818         BaseType_t xReturn;
2819         Queue_t * const pxQueueOrSemaphore = ( Queue_t * ) xQueueOrSemaphore;
2820
2821                 if( pxQueueOrSemaphore->pxQueueSetContainer != xQueueSet )
2822                 {
2823                         /* The queue was not a member of the set. */
2824                         xReturn = pdFAIL;
2825                 }
2826                 else if( pxQueueOrSemaphore->uxMessagesWaiting != ( UBaseType_t ) 0 )
2827                 {
2828                         /* It is dangerous to remove a queue from a set when the queue is
2829                         not empty because the queue set will still hold pending events for
2830                         the queue. */
2831                         xReturn = pdFAIL;
2832                 }
2833                 else
2834                 {
2835                         taskENTER_CRITICAL();
2836                         {
2837                                 /* The queue is no longer contained in the set. */
2838                                 pxQueueOrSemaphore->pxQueueSetContainer = NULL;
2839                         }
2840                         taskEXIT_CRITICAL();
2841                         xReturn = pdPASS;
2842                 }
2843
2844                 return xReturn;
2845         } /*lint !e818 xQueueSet could not be declared as pointing to const as it is a typedef. */
2846
2847 #endif /* configUSE_QUEUE_SETS */
2848 /*-----------------------------------------------------------*/
2849
2850 #if ( configUSE_QUEUE_SETS == 1 )
2851
2852         QueueSetMemberHandle_t xQueueSelectFromSet( QueueSetHandle_t xQueueSet, TickType_t const xTicksToWait )
2853         {
2854         QueueSetMemberHandle_t xReturn = NULL;
2855
2856                 ( void ) xQueueReceive( ( QueueHandle_t ) xQueueSet, &xReturn, xTicksToWait ); /*lint !e961 Casting from one typedef to another is not redundant. */
2857                 return xReturn;
2858         }
2859
2860 #endif /* configUSE_QUEUE_SETS */
2861 /*-----------------------------------------------------------*/
2862
2863 #if ( configUSE_QUEUE_SETS == 1 )
2864
2865         QueueSetMemberHandle_t xQueueSelectFromSetFromISR( QueueSetHandle_t xQueueSet )
2866         {
2867         QueueSetMemberHandle_t xReturn = NULL;
2868
2869                 ( void ) xQueueReceiveFromISR( ( QueueHandle_t ) xQueueSet, &xReturn, NULL ); /*lint !e961 Casting from one typedef to another is not redundant. */
2870                 return xReturn;
2871         }
2872
2873 #endif /* configUSE_QUEUE_SETS */
2874 /*-----------------------------------------------------------*/
2875
2876 #if ( configUSE_QUEUE_SETS == 1 )
2877
2878         static BaseType_t prvNotifyQueueSetContainer( const Queue_t * const pxQueue, const BaseType_t xCopyPosition )
2879         {
2880         Queue_t *pxQueueSetContainer = pxQueue->pxQueueSetContainer;
2881         BaseType_t xReturn = pdFALSE;
2882
2883                 /* This function must be called form a critical section. */
2884
2885                 configASSERT( pxQueueSetContainer );
2886                 configASSERT( pxQueueSetContainer->uxMessagesWaiting < pxQueueSetContainer->uxLength );
2887
2888                 if( pxQueueSetContainer->uxMessagesWaiting < pxQueueSetContainer->uxLength )
2889                 {
2890                         const int8_t cTxLock = pxQueueSetContainer->cTxLock;
2891
2892                         traceQUEUE_SEND( pxQueueSetContainer );
2893
2894                         /* The data copied is the handle of the queue that contains data. */
2895                         xReturn = prvCopyDataToQueue( pxQueueSetContainer, &pxQueue, xCopyPosition );
2896
2897                         if( cTxLock == queueUNLOCKED )
2898                         {
2899                                 if( listLIST_IS_EMPTY( &( pxQueueSetContainer->xTasksWaitingToReceive ) ) == pdFALSE )
2900                                 {
2901                                         if( xTaskRemoveFromEventList( &( pxQueueSetContainer->xTasksWaitingToReceive ) ) != pdFALSE )
2902                                         {
2903                                                 /* The task waiting has a higher priority. */
2904                                                 xReturn = pdTRUE;
2905                                         }
2906                                         else
2907                                         {
2908                                                 mtCOVERAGE_TEST_MARKER();
2909                                         }
2910                                 }
2911                                 else
2912                                 {
2913                                         mtCOVERAGE_TEST_MARKER();
2914                                 }
2915                         }
2916                         else
2917                         {
2918                                 pxQueueSetContainer->cTxLock = ( int8_t ) ( cTxLock + 1 );
2919                         }
2920                 }
2921                 else
2922                 {
2923                         mtCOVERAGE_TEST_MARKER();
2924                 }
2925
2926                 return xReturn;
2927         }
2928
2929 #endif /* configUSE_QUEUE_SETS */
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941