| /* | |
| FreeRTOS V7.2.0 - Copyright (C) 2012 Real Time Engineers Ltd. | |
| *************************************************************************** | |
| * * | |
| * FreeRTOS tutorial books are available in pdf and paperback. * | |
| * Complete, revised, and edited pdf reference manuals are also * | |
| * available. * | |
| * * | |
| * Purchasing FreeRTOS documentation will not only help you, by * | |
| * ensuring you get running as quickly as possible and with an * | |
| * in-depth knowledge of how to use FreeRTOS, it will also help * | |
| * the FreeRTOS project to continue with its mission of providing * | |
| * professional grade, cross platform, de facto standard solutions * | |
| * for microcontrollers - completely free of charge! * | |
| * * | |
| * >>> See http://www.FreeRTOS.org/Documentation for details. <<< * | |
| * * | |
| * Thank you for using FreeRTOS, and thank you for your support! * | |
| * * | |
| *************************************************************************** | |
| This file is part of the FreeRTOS distribution. | |
| FreeRTOS is free software; you can redistribute it and/or modify it under | |
| the terms of the GNU General Public License (version 2) as published by the | |
| Free Software Foundation AND MODIFIED BY the FreeRTOS exception. | |
| >>>NOTE<<< The modification to the GPL is included to allow you to | |
| distribute a combined work that includes FreeRTOS without being obliged to | |
| provide the source code for proprietary components outside of the FreeRTOS | |
| kernel. FreeRTOS is distributed in the hope that it will be useful, but | |
| WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY | |
| or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
| more details. You should have received a copy of the GNU General Public | |
| License and the FreeRTOS license exception along with FreeRTOS; if not it | |
| can be viewed here: http://www.freertos.org/a00114.html and also obtained | |
| by writing to Richard Barry, contact details for whom are available on the | |
| FreeRTOS WEB site. | |
| 1 tab == 4 spaces! | |
| *************************************************************************** | |
| * * | |
| * Having a problem? Start by reading the FAQ "My application does * | |
| * not run, what could be wrong? * | |
| * * | |
| * http://www.FreeRTOS.org/FAQHelp.html * | |
| * * | |
| *************************************************************************** | |
| http://www.FreeRTOS.org - Documentation, training, latest information, | |
| license and contact details. | |
| http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products, | |
| including FreeRTOS+Trace - an indispensable productivity tool. | |
| Real Time Engineers ltd license FreeRTOS to High Integrity Systems, who sell | |
| the code with commercial support, indemnification, and middleware, under | |
| the OpenRTOS brand: http://www.OpenRTOS.com. High Integrity Systems also | |
| provide a safety engineered and independently SIL3 certified version under | |
| the SafeRTOS brand: http://www.SafeRTOS.com. | |
| */ | |
| #include <stdlib.h> | |
| #include <string.h> | |
| /* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining | |
| all the API functions to use the MPU wrappers. That should only be done when | |
| task.h is included from an application file. */ | |
| #define MPU_WRAPPERS_INCLUDED_FROM_API_FILE | |
| #include "FreeRTOS.h" | |
| #include "task.h" | |
| #include "static-allocator.h" | |
| #if ( configUSE_CO_ROUTINES == 1 ) | |
| #include "croutine.h" | |
| #endif | |
| #undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE | |
| /*----------------------------------------------------------- | |
| * PUBLIC LIST API documented in list.h | |
| *----------------------------------------------------------*/ | |
| /* Constants used with the cRxLock and xTxLock structure members. */ | |
| #define queueUNLOCKED ( ( signed portBASE_TYPE ) -1 ) | |
| #define queueLOCKED_UNMODIFIED ( ( signed portBASE_TYPE ) 0 ) | |
| #define queueERRONEOUS_UNBLOCK ( -1 ) | |
| /* For internal use only. */ | |
| #define queueSEND_TO_BACK ( 0 ) | |
| #define queueSEND_TO_FRONT ( 1 ) | |
| /* Effectively make a union out of the xQUEUE structure. */ | |
| #define pxMutexHolder pcTail | |
| #define uxQueueType pcHead | |
| #define uxRecursiveCallCount pcReadFrom | |
| #define queueQUEUE_IS_MUTEX NULL | |
| /* Semaphores do not actually store or copy data, so have an items size of | |
| zero. */ | |
| #define queueSEMAPHORE_QUEUE_ITEM_LENGTH ( ( unsigned portBASE_TYPE ) 0 ) | |
| #define queueDONT_BLOCK ( ( portTickType ) 0U ) | |
| #define queueMUTEX_GIVE_BLOCK_TIME ( ( portTickType ) 0U ) | |
| /* These definitions *must* match those in queue.h. */ | |
| #define queueQUEUE_TYPE_BASE ( 0U ) | |
| #define queueQUEUE_TYPE_MUTEX ( 1U ) | |
| #define queueQUEUE_TYPE_COUNTING_SEMAPHORE ( 2U ) | |
| #define queueQUEUE_TYPE_BINARY_SEMAPHORE ( 3U ) | |
| #define queueQUEUE_TYPE_RECURSIVE_MUTEX ( 4U ) | |
| /* | |
| * Definition of the queue used by the scheduler. | |
| * Items are queued by copy, not reference. | |
| */ | |
| typedef struct QueueDefinition | |
| { | |
| signed char *pcHead; /*< Points to the beginning of the queue storage area. */ | |
| signed char *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. */ | |
| signed char *pcWriteTo; /*< Points to the free next place in the storage area. */ | |
| signed char *pcReadFrom; /*< Points to the last place that a queued item was read from. */ | |
| xList xTasksWaitingToSend; /*< List of tasks that are blocked waiting to post onto this queue. Stored in priority order. */ | |
| xList xTasksWaitingToReceive; /*< List of tasks that are blocked waiting to read from this queue. Stored in priority order. */ | |
| volatile unsigned portBASE_TYPE uxMessagesWaiting;/*< The number of items currently in the queue. */ | |
| unsigned portBASE_TYPE uxLength; /*< The length of the queue defined as the number of items it will hold, not the number of bytes. */ | |
| unsigned portBASE_TYPE uxItemSize; /*< The size of each items that the queue will hold. */ | |
| volatile signed portBASE_TYPE xRxLock; /*< 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. */ | |
| volatile signed portBASE_TYPE xTxLock; /*< 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. */ | |
| unsigned char ucQueueType; | |
| #if ( configUSE_TRACE_FACILITY == 1 ) | |
| unsigned char ucQueueNumber; | |
| #endif | |
| } xQUEUE; | |
| /*-----------------------------------------------------------*/ | |
| /* | |
| * Inside this file xQueueHandle is a pointer to a xQUEUE structure. | |
| * To keep the definition private the API header file defines it as a | |
| * pointer to void. | |
| */ | |
| typedef xQUEUE * xQueueHandle; | |
| /* | |
| * Prototypes for public functions are included here so we don't have to | |
| * include the API header file (as it defines xQueueHandle differently). These | |
| * functions are documented in the API header file. | |
| */ | |
| void xInitQueues(void); | |
| xQueueHandle xQueueGenericCreate( void* , unsigned portBASE_TYPE uxQueueLength, unsigned portBASE_TYPE uxItemSize, unsigned char ucQueueType ) PRIVILEGED_FUNCTION; | |
| signed portBASE_TYPE xQueueGenericSend( xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition ) PRIVILEGED_FUNCTION; | |
| unsigned portBASE_TYPE uxQueueMessagesWaiting( const xQueueHandle pxQueue ) PRIVILEGED_FUNCTION; | |
| void vQueueDelete( xQueueHandle xQueue ) PRIVILEGED_FUNCTION; | |
| signed portBASE_TYPE xQueueGenericSendFromISR( xQueueHandle pxQueue, const void * const pvItemToQueue, signed portBASE_TYPE *pxHigherPriorityTaskWoken, portBASE_TYPE xCopyPosition ) PRIVILEGED_FUNCTION; | |
| signed portBASE_TYPE xQueueGenericReceive( xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking ) PRIVILEGED_FUNCTION; | |
| signed portBASE_TYPE xQueueReceiveFromISR( xQueueHandle pxQueue, void * const pvBuffer, signed portBASE_TYPE *pxHigherPriorityTaskWoken ) PRIVILEGED_FUNCTION; | |
| xQueueHandle xQueueCreateMutex( unsigned char ucQueueType ) PRIVILEGED_FUNCTION; | |
| xQueueHandle xQueueCreateCountingSemaphore( unsigned portBASE_TYPE uxCountValue, unsigned portBASE_TYPE uxInitialCount ) PRIVILEGED_FUNCTION; | |
| portBASE_TYPE xQueueTakeMutexRecursive( xQueueHandle xMutex, portTickType xBlockTime ) PRIVILEGED_FUNCTION; | |
| portBASE_TYPE xQueueGiveMutexRecursive( xQueueHandle xMutex ) PRIVILEGED_FUNCTION; | |
| signed portBASE_TYPE xQueueAltGenericSend( xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition ) PRIVILEGED_FUNCTION; | |
| signed portBASE_TYPE xQueueAltGenericReceive( xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking ) PRIVILEGED_FUNCTION; | |
| signed portBASE_TYPE xQueueIsQueueEmptyFromISR( const xQueueHandle pxQueue ) PRIVILEGED_FUNCTION; | |
| signed portBASE_TYPE xQueueIsQueueFullFromISR( const xQueueHandle pxQueue ) PRIVILEGED_FUNCTION; | |
| unsigned portBASE_TYPE uxQueueMessagesWaitingFromISR( const xQueueHandle pxQueue ) PRIVILEGED_FUNCTION; | |
| void vQueueWaitForMessageRestricted( xQueueHandle pxQueue, portTickType xTicksToWait ) PRIVILEGED_FUNCTION; | |
| unsigned char ucQueueGetQueueNumber( xQueueHandle pxQueue ) PRIVILEGED_FUNCTION; | |
| void vQueueSetQueueNumber( xQueueHandle pxQueue, unsigned char ucQueueNumber ) PRIVILEGED_FUNCTION; | |
| unsigned char ucQueueGetQueueType( xQueueHandle pxQueue ) PRIVILEGED_FUNCTION; | |
| portBASE_TYPE xQueueGenericReset( xQueueHandle pxQueue, portBASE_TYPE xNewQueue ) PRIVILEGED_FUNCTION; | |
| xTaskHandle xQueueGetMutexHolder( xQueueHandle xSemaphore ) PRIVILEGED_FUNCTION; | |
| /* | |
| * Co-routine queue functions differ from task queue functions. Co-routines are | |
| * an optional component. | |
| */ | |
| #if configUSE_CO_ROUTINES == 1 | |
| signed portBASE_TYPE xQueueCRSendFromISR( xQueueHandle pxQueue, const void *pvItemToQueue, signed portBASE_TYPE xCoRoutinePreviouslyWoken ) PRIVILEGED_FUNCTION; | |
| signed portBASE_TYPE xQueueCRReceiveFromISR( xQueueHandle pxQueue, void *pvBuffer, signed portBASE_TYPE *pxTaskWoken ) PRIVILEGED_FUNCTION; | |
| signed portBASE_TYPE xQueueCRSend( xQueueHandle pxQueue, const void *pvItemToQueue, portTickType xTicksToWait ) PRIVILEGED_FUNCTION; | |
| signed portBASE_TYPE xQueueCRReceive( xQueueHandle pxQueue, void *pvBuffer, portTickType xTicksToWait ) PRIVILEGED_FUNCTION; | |
| #endif | |
| #define ARRAY_SIZE(a) (sizeof(a)/sizeof(a[0])) | |
| #ifndef configMAX_NUM_OF_QUEUES | |
| #define configMAX_NUM_OF_QUEUES (64) | |
| #endif | |
| #define NUM_OF_QUEUE_FLAGS ((configMAX_NUM_OF_QUEUES+31)/32) | |
| static xQUEUE sNlQueues[configMAX_NUM_OF_QUEUES]; | |
| static uint32_t sNlQueuesFlags[NUM_OF_QUEUE_FLAGS]; | |
| static static_pool_t sQueuesPool; | |
| #if configUSE_COUNTING_SEMAPHORES == 1 | |
| static uint8_t sNlCountingSemaphores[configMAX_COUNTING_SEMAPHORES]; | |
| #define MAX_COUNTING_SEMAPHORES_FLAGS ((configMAX_COUNTING_SEMAPHORES+31)/32) | |
| static uint32_t sNlCountingSemaphoresFlags[MAX_COUNTING_SEMAPHORES_FLAGS]; | |
| static static_pool_t sSemaphoresPool; | |
| xQueueHandle xSemaphoreCreateBinary(void); | |
| #endif | |
| // xxx | |
| #define semSEMAPHORE_QUEUE_ITEM_LENGTH ( ( unsigned char ) 0U ) | |
| xQueueHandle xSemaphoreCreateBinary(void) | |
| { | |
| void* binarySema = poolAllocateBuffer(&sSemaphoresPool); | |
| xQueueHandle retval = xQueueGenericCreate( binarySema, ( unsigned portBASE_TYPE ) 1, semSEMAPHORE_QUEUE_ITEM_LENGTH, queueQUEUE_TYPE_BINARY_SEMAPHORE ); | |
| if(retval != NULL ) | |
| { | |
| // xSemaphoreGive | |
| xQueueGenericSend( retval, | |
| NULL, | |
| 0, // block time | |
| queueSEND_TO_BACK ); | |
| } | |
| return retval; | |
| } | |
| void xInitQueues(void) | |
| { | |
| poolInit( &sQueuesPool, | |
| sizeof(sNlQueues[0]), | |
| ARRAY_SIZE(sNlQueues), | |
| &sNlQueues, | |
| &sNlQueuesFlags); | |
| #if configUSE_COUNTING_SEMAPHORES == 1 | |
| poolInit( &sSemaphoresPool, | |
| sizeof(sNlCountingSemaphores[0]), | |
| ARRAY_SIZE(sNlCountingSemaphores), | |
| &sNlCountingSemaphores, | |
| &sNlCountingSemaphoresFlags); | |
| #endif | |
| } | |
| /* | |
| * The queue registry is just a means for kernel aware debuggers to locate | |
| * queue structures. It has no other purpose so is an optional component. | |
| */ | |
| #if configQUEUE_REGISTRY_SIZE > 0 | |
| /* The type stored within the queue registry array. This allows a name | |
| to be assigned to each queue making kernel aware debugging a little | |
| more user friendly. */ | |
| typedef struct QUEUE_REGISTRY_ITEM | |
| { | |
| signed char *pcQueueName; | |
| xQueueHandle xHandle; | |
| } xQueueRegistryItem; | |
| /* The queue registry is simply an array of xQueueRegistryItem structures. | |
| The pcQueueName member of a structure being NULL is indicative of the | |
| array position being vacant. */ | |
| xQueueRegistryItem xQueueRegistry[ configQUEUE_REGISTRY_SIZE ]; | |
| /* Removes a queue from the registry by simply setting the pcQueueName | |
| member to NULL. */ | |
| static void vQueueUnregisterQueue( xQueueHandle xQueue ) PRIVILEGED_FUNCTION; | |
| void vQueueAddToRegistry( xQueueHandle xQueue, signed char *pcQueueName ) PRIVILEGED_FUNCTION; | |
| #endif | |
| /* | |
| * Unlocks a queue locked by a call to prvLockQueue. Locking a queue does not | |
| * prevent an ISR from adding or removing items to the queue, but does prevent | |
| * an ISR from removing tasks from the queue event lists. If an ISR finds a | |
| * queue is locked it will instead increment the appropriate queue lock count | |
| * to indicate that a task may require unblocking. When the queue in unlocked | |
| * these lock counts are inspected, and the appropriate action taken. | |
| */ | |
| static void prvUnlockQueue( xQueueHandle pxQueue ) PRIVILEGED_FUNCTION; | |
| /* | |
| * Uses a critical section to determine if there is any data in a queue. | |
| * | |
| * @return pdTRUE if the queue contains no items, otherwise pdFALSE. | |
| */ | |
| static signed portBASE_TYPE prvIsQueueEmpty( const xQueueHandle pxQueue ) PRIVILEGED_FUNCTION; | |
| /* | |
| * Uses a critical section to determine if there is any space in a queue. | |
| * | |
| * @return pdTRUE if there is no space, otherwise pdFALSE; | |
| */ | |
| static signed portBASE_TYPE prvIsQueueFull( const xQueueHandle pxQueue ) PRIVILEGED_FUNCTION; | |
| /* | |
| * Copies an item into the queue, either at the front of the queue or the | |
| * back of the queue. | |
| */ | |
| static void prvCopyDataToQueue( xQUEUE *pxQueue, const void *pvItemToQueue, portBASE_TYPE xPosition ) PRIVILEGED_FUNCTION; | |
| /* | |
| * Copies an item out of a queue. | |
| */ | |
| static void prvCopyDataFromQueue( xQUEUE * const pxQueue, const void *pvBuffer ) PRIVILEGED_FUNCTION; | |
| /*-----------------------------------------------------------*/ | |
| /* | |
| * Macro to mark a queue as locked. Locking a queue prevents an ISR from | |
| * accessing the queue event lists. | |
| */ | |
| #define prvLockQueue( pxQueue ) \ | |
| taskENTER_CRITICAL(); \ | |
| { \ | |
| if( ( pxQueue )->xRxLock == queueUNLOCKED ) \ | |
| { \ | |
| ( pxQueue )->xRxLock = queueLOCKED_UNMODIFIED; \ | |
| } \ | |
| if( ( pxQueue )->xTxLock == queueUNLOCKED ) \ | |
| { \ | |
| ( pxQueue )->xTxLock = queueLOCKED_UNMODIFIED; \ | |
| } \ | |
| } \ | |
| taskEXIT_CRITICAL() | |
| /*-----------------------------------------------------------*/ | |
| /*----------------------------------------------------------- | |
| * PUBLIC QUEUE MANAGEMENT API documented in queue.h | |
| *----------------------------------------------------------*/ | |
| portBASE_TYPE xQueueGenericReset( xQueueHandle pxQueue, portBASE_TYPE xNewQueue ) | |
| { | |
| configASSERT( pxQueue ); | |
| taskENTER_CRITICAL(); | |
| { | |
| pxQueue->pcTail = pxQueue->pcHead + ( pxQueue->uxLength * pxQueue->uxItemSize ); | |
| pxQueue->uxMessagesWaiting = ( unsigned portBASE_TYPE ) 0U; | |
| pxQueue->pcWriteTo = pxQueue->pcHead; | |
| pxQueue->pcReadFrom = pxQueue->pcHead + ( ( pxQueue->uxLength - ( unsigned portBASE_TYPE ) 1U ) * pxQueue->uxItemSize ); | |
| pxQueue->xRxLock = queueUNLOCKED; | |
| pxQueue->xTxLock = queueUNLOCKED; | |
| if( xNewQueue == pdFALSE ) | |
| { | |
| /* If there are tasks blocked waiting to read from the queue, then | |
| the tasks will remain blocked as after this function exits the queue | |
| will still be empty. If there are tasks blocked waiting to write to | |
| the queue, then one should be unblocked as after this function exits | |
| it will be possible to write to it. */ | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE ) | |
| { | |
| if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) == pdTRUE ) | |
| { | |
| portYIELD_WITHIN_API(); | |
| } | |
| } | |
| } | |
| else | |
| { | |
| /* Ensure the event queues start in the correct state. */ | |
| vListInitialise( &( pxQueue->xTasksWaitingToSend ) ); | |
| vListInitialise( &( pxQueue->xTasksWaitingToReceive ) ); | |
| } | |
| } | |
| taskEXIT_CRITICAL(); | |
| /* A value is returned for calling semantic consistency with previous | |
| versions. */ | |
| return pdPASS; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| xQueueHandle xQueueGenericCreate( void* queueBuffer, | |
| unsigned portBASE_TYPE uxQueueLength, | |
| unsigned portBASE_TYPE uxItemSize, | |
| unsigned char ucQueueType ) | |
| { | |
| xQUEUE *pxNewQueue = (xQUEUE *)0xdeadbeef; | |
| xQueueHandle xReturn = NULL; | |
| /* Allocate the new queue structure. */ | |
| if( uxQueueLength > ( unsigned portBASE_TYPE ) 0 ) | |
| { | |
| pxNewQueue = (xQUEUE*) poolAllocateBuffer(&sQueuesPool); | |
| if( pxNewQueue != NULL ) | |
| { | |
| pxNewQueue->pcHead = ( signed char * ) queueBuffer; | |
| if( pxNewQueue->pcHead != NULL ) | |
| { | |
| /* Initialise the queue members as described above where the | |
| queue type is defined. */ | |
| pxNewQueue->uxLength = uxQueueLength; | |
| pxNewQueue->uxItemSize = uxItemSize; | |
| xQueueGenericReset( pxNewQueue, pdTRUE ); | |
| pxNewQueue->ucQueueType = ucQueueType; | |
| traceQUEUE_CREATE( pxNewQueue ); | |
| xReturn = pxNewQueue; | |
| } | |
| else | |
| { | |
| traceQUEUE_CREATE_FAILED( ucQueueType ); | |
| poolFreeBuffer( &sQueuesPool, pxNewQueue ); | |
| } | |
| } | |
| } | |
| configASSERT( xReturn ); | |
| return xReturn; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| #if ( configUSE_MUTEXES == 1 ) | |
| xQueueHandle xQueueCreateMutex( unsigned char ucQueueType ) | |
| { | |
| xQUEUE *pxNewQueue; | |
| /* Prevent compiler warnings about unused parameters if | |
| configUSE_TRACE_FACILITY does not equal 1. */ | |
| ( void ) ucQueueType; | |
| /* Allocate the new queue structure. */ | |
| pxNewQueue = (xQUEUE*) poolAllocateBuffer(&sQueuesPool); | |
| if( pxNewQueue != NULL ) | |
| { | |
| /* Information required for priority inheritance. */ | |
| pxNewQueue->pxMutexHolder = NULL; | |
| pxNewQueue->uxQueueType = queueQUEUE_IS_MUTEX; | |
| /* Queues used as a mutex no data is actually copied into or out | |
| of the queue. */ | |
| pxNewQueue->pcWriteTo = NULL; | |
| pxNewQueue->pcReadFrom = NULL; | |
| /* Each mutex has a length of 1 (like a binary semaphore) and | |
| an item size of 0 as nothing is actually copied into or out | |
| of the mutex. */ | |
| pxNewQueue->uxMessagesWaiting = ( unsigned portBASE_TYPE ) 0U; | |
| pxNewQueue->uxLength = ( unsigned portBASE_TYPE ) 1U; | |
| pxNewQueue->uxItemSize = ( unsigned portBASE_TYPE ) 0U; | |
| pxNewQueue->xRxLock = queueUNLOCKED; | |
| pxNewQueue->xTxLock = queueUNLOCKED; | |
| pxNewQueue->ucQueueType = ucQueueType; | |
| /* Ensure the event queues start with the correct state. */ | |
| vListInitialise( &( pxNewQueue->xTasksWaitingToSend ) ); | |
| vListInitialise( &( pxNewQueue->xTasksWaitingToReceive ) ); | |
| traceCREATE_MUTEX( pxNewQueue ); | |
| /* Start with the semaphore in the expected state. */ | |
| xQueueGenericSend( pxNewQueue, NULL, ( portTickType ) 0U, queueSEND_TO_BACK ); | |
| } | |
| else | |
| { | |
| traceCREATE_MUTEX_FAILED(); | |
| } | |
| configASSERT( pxNewQueue ); | |
| return pxNewQueue; | |
| } | |
| #endif /* configUSE_MUTEXES */ | |
| /*-----------------------------------------------------------*/ | |
| #if ( ( configUSE_MUTEXES == 1 ) && ( INCLUDE_xQueueGetMutexHolder == 1 ) ) | |
| void* xQueueGetMutexHolder( xQueueHandle xSemaphore ) | |
| { | |
| void *pxReturn; | |
| /* This function is called by xSemaphoreGetMutexHolder(), and should not | |
| be called directly. Note: This is is a good way of determining if the | |
| calling task is the mutex holder, but not a good way of determining the | |
| identity of the mutex holder, as the holder may change between the | |
| following critical section exiting and the function returning. */ | |
| taskENTER_CRITICAL(); | |
| { | |
| if( xSemaphore->uxQueueType == queueQUEUE_IS_MUTEX ) | |
| { | |
| pxReturn = ( void * ) xSemaphore->pxMutexHolder; | |
| } | |
| else | |
| { | |
| pxReturn = NULL; | |
| } | |
| } | |
| taskEXIT_CRITICAL(); | |
| return pxReturn; | |
| } | |
| #endif | |
| /*-----------------------------------------------------------*/ | |
| #if ( configUSE_RECURSIVE_MUTEXES == 1 ) | |
| portBASE_TYPE xQueueGiveMutexRecursive( xQueueHandle pxMutex ) | |
| { | |
| portBASE_TYPE xReturn; | |
| configASSERT( pxMutex ); | |
| /* If this is the task that holds the mutex then pxMutexHolder will not | |
| change outside of this task. If this task does not hold the mutex then | |
| pxMutexHolder can never coincidentally equal the tasks handle, and as | |
| this is the only condition we are interested in it does not matter if | |
| pxMutexHolder is accessed simultaneously by another task. Therefore no | |
| mutual exclusion is required to test the pxMutexHolder variable. */ | |
| if( pxMutex->pxMutexHolder == xTaskGetCurrentTaskHandle() ) | |
| { | |
| traceGIVE_MUTEX_RECURSIVE( pxMutex ); | |
| /* uxRecursiveCallCount cannot be zero if pxMutexHolder is equal to | |
| the task handle, therefore no underflow check is required. Also, | |
| uxRecursiveCallCount is only modified by the mutex holder, and as | |
| there can only be one, no mutual exclusion is required to modify the | |
| uxRecursiveCallCount member. */ | |
| /* | |
| ( pxMutex->uxRecursiveCallCount )--; | |
| if( pxMutex->uxRecursiveCallCount == 0 ) | |
| Here we use uxRecursiveCallCount(which is a pointer) as integer, the compiler | |
| will assume it would never be NULL when we do ++/--, hence the if statement was | |
| always optimized out. We force cast to int to work around this.*/ | |
| unsigned portBASE_TYPE tmp = (unsigned portBASE_TYPE) (pxMutex->uxRecursiveCallCount); | |
| tmp -= sizeof(*pxMutex->uxRecursiveCallCount); | |
| pxMutex->uxRecursiveCallCount = (signed char*) tmp; | |
| /* Have we unwound the call count? */ | |
| if( tmp == 0 ) | |
| { | |
| /* Return the mutex. This will automatically unblock any other | |
| task that might be waiting to access the mutex. */ | |
| xQueueGenericSend( pxMutex, NULL, queueMUTEX_GIVE_BLOCK_TIME, queueSEND_TO_BACK ); | |
| } | |
| xReturn = pdPASS; | |
| } | |
| else | |
| { | |
| /* We cannot give the mutex because we are not the holder. */ | |
| xReturn = pdFAIL; | |
| traceGIVE_MUTEX_RECURSIVE_FAILED( pxMutex ); | |
| } | |
| return xReturn; | |
| } | |
| #endif /* configUSE_RECURSIVE_MUTEXES */ | |
| /*-----------------------------------------------------------*/ | |
| #if configUSE_RECURSIVE_MUTEXES == 1 | |
| portBASE_TYPE xQueueTakeMutexRecursive( xQueueHandle pxMutex, portTickType xBlockTime ) | |
| { | |
| portBASE_TYPE xReturn; | |
| configASSERT( pxMutex ); | |
| /* Comments regarding mutual exclusion as per those within | |
| xQueueGiveMutexRecursive(). */ | |
| traceTAKE_MUTEX_RECURSIVE( pxMutex ); | |
| if( pxMutex->pxMutexHolder == xTaskGetCurrentTaskHandle() ) | |
| { | |
| ( pxMutex->uxRecursiveCallCount )++; | |
| xReturn = pdPASS; | |
| } | |
| else | |
| { | |
| xReturn = xQueueGenericReceive( pxMutex, NULL, xBlockTime, pdFALSE ); | |
| /* pdPASS will only be returned if we successfully obtained the mutex, | |
| we may have blocked to reach here. */ | |
| if( xReturn == pdPASS ) | |
| { | |
| ( pxMutex->uxRecursiveCallCount )++; | |
| } | |
| else | |
| { | |
| traceTAKE_MUTEX_RECURSIVE_FAILED( pxMutex ); | |
| } | |
| } | |
| return xReturn; | |
| } | |
| #endif /* configUSE_RECURSIVE_MUTEXES */ | |
| /*-----------------------------------------------------------*/ | |
| #if configUSE_COUNTING_SEMAPHORES == 1 | |
| xQueueHandle xQueueCreateCountingSemaphore( unsigned portBASE_TYPE uxCountValue, unsigned portBASE_TYPE uxInitialCount ) | |
| { | |
| xQueueHandle pxHandle; | |
| void* semaBackingStore = poolAllocateBuffer(&sSemaphoresPool); | |
| configASSERT( semaBackingStore ); | |
| pxHandle = xQueueGenericCreate( semaBackingStore, ( unsigned portBASE_TYPE ) uxCountValue, queueSEMAPHORE_QUEUE_ITEM_LENGTH, queueQUEUE_TYPE_COUNTING_SEMAPHORE ); | |
| if( pxHandle != NULL ) | |
| { | |
| pxHandle->uxMessagesWaiting = uxInitialCount; | |
| traceCREATE_COUNTING_SEMAPHORE(); | |
| } | |
| else | |
| { | |
| traceCREATE_COUNTING_SEMAPHORE_FAILED(); | |
| } | |
| configASSERT( pxHandle ); | |
| return pxHandle; | |
| } | |
| #endif /* configUSE_COUNTING_SEMAPHORES */ | |
| /*-----------------------------------------------------------*/ | |
| signed portBASE_TYPE xQueueGenericSend( xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition ) | |
| { | |
| signed portBASE_TYPE xEntryTimeSet = pdFALSE; | |
| xTimeOutType xTimeOut; | |
| configASSERT( pxQueue ); | |
| configASSERT( !( ( pvItemToQueue == NULL ) && ( pxQueue->uxItemSize != ( unsigned portBASE_TYPE ) 0U ) ) ); | |
| /* This function relaxes the coding standard somewhat to allow return | |
| statements within the function itself. This is done in the interest | |
| of execution time efficiency. */ | |
| for( ;; ) | |
| { | |
| taskENTER_CRITICAL(); | |
| { | |
| /* Is there room on the queue now? To be running we must be | |
| the highest priority task wanting to access the queue. */ | |
| if( pxQueue->uxMessagesWaiting < pxQueue->uxLength ) | |
| { | |
| traceQUEUE_SEND( pxQueue ); | |
| prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition ); | |
| /* If there was a task waiting for data to arrive on the | |
| queue then unblock it now. */ | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE ) | |
| { | |
| if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) == pdTRUE ) | |
| { | |
| /* The unblocked task has a priority higher than | |
| our own so yield immediately. Yes it is ok to do | |
| this from within the critical section - the kernel | |
| takes care of that. */ | |
| portYIELD_WITHIN_API(); | |
| } | |
| } | |
| taskEXIT_CRITICAL(); | |
| /* Return to the original privilege level before exiting the | |
| function. */ | |
| return pdPASS; | |
| } | |
| else | |
| { | |
| if( xTicksToWait == ( portTickType ) 0 ) | |
| { | |
| /* The queue was full and no block time is specified (or | |
| the block time has expired) so leave now. */ | |
| taskEXIT_CRITICAL(); | |
| /* Return to the original privilege level before exiting | |
| the function. */ | |
| traceQUEUE_SEND_FAILED( pxQueue ); | |
| return errQUEUE_FULL; | |
| } | |
| else if( xEntryTimeSet == pdFALSE ) | |
| { | |
| /* The queue was full and a block time was specified so | |
| configure the timeout structure. */ | |
| vTaskSetTimeOutState( &xTimeOut ); | |
| xEntryTimeSet = pdTRUE; | |
| } | |
| } | |
| } | |
| taskEXIT_CRITICAL(); | |
| /* Interrupts and other tasks can send to and receive from the queue | |
| now the critical section has been exited. */ | |
| vTaskSuspendAll(); | |
| prvLockQueue( pxQueue ); | |
| /* Update the timeout state to see if it has expired yet. */ | |
| if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE ) | |
| { | |
| if( prvIsQueueFull( pxQueue ) != pdFALSE ) | |
| { | |
| traceBLOCKING_ON_QUEUE_SEND( pxQueue ); | |
| vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToSend ), xTicksToWait ); | |
| /* Unlocking the queue means queue events can effect the | |
| event list. It is possible that interrupts occurring now | |
| remove this task from the event list again - but as the | |
| scheduler is suspended the task will go onto the pending | |
| ready last instead of the actual ready list. */ | |
| prvUnlockQueue( pxQueue ); | |
| /* Resuming the scheduler will move tasks from the pending | |
| ready list into the ready list - so it is feasible that this | |
| task is already in a ready list before it yields - in which | |
| case the yield will not cause a context switch unless there | |
| is also a higher priority task in the pending ready list. */ | |
| if( xTaskResumeAll() == pdFALSE ) | |
| { | |
| portYIELD_WITHIN_API(); | |
| } | |
| } | |
| else | |
| { | |
| /* Try again. */ | |
| prvUnlockQueue( pxQueue ); | |
| ( void ) xTaskResumeAll(); | |
| } | |
| } | |
| else | |
| { | |
| /* The timeout has expired. */ | |
| prvUnlockQueue( pxQueue ); | |
| ( void ) xTaskResumeAll(); | |
| /* Return to the original privilege level before exiting the | |
| function. */ | |
| traceQUEUE_SEND_FAILED( pxQueue ); | |
| return errQUEUE_FULL; | |
| } | |
| } | |
| } | |
| /*-----------------------------------------------------------*/ | |
| #if configUSE_ALTERNATIVE_API == 1 | |
| signed portBASE_TYPE xQueueAltGenericSend( xQueueHandle pxQueue, const void * const pvItemToQueue, portTickType xTicksToWait, portBASE_TYPE xCopyPosition ) | |
| { | |
| signed portBASE_TYPE xEntryTimeSet = pdFALSE; | |
| xTimeOutType xTimeOut; | |
| configASSERT( pxQueue ); | |
| configASSERT( !( ( pvItemToQueue == NULL ) && ( pxQueue->uxItemSize != ( unsigned portBASE_TYPE ) 0U ) ) ); | |
| for( ;; ) | |
| { | |
| taskENTER_CRITICAL(); | |
| { | |
| /* Is there room on the queue now? To be running we must be | |
| the highest priority task wanting to access the queue. */ | |
| if( pxQueue->uxMessagesWaiting < pxQueue->uxLength ) | |
| { | |
| traceQUEUE_SEND( pxQueue ); | |
| prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition ); | |
| /* If there was a task waiting for data to arrive on the | |
| queue then unblock it now. */ | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE ) | |
| { | |
| if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) == pdTRUE ) | |
| { | |
| /* The unblocked task has a priority higher than | |
| our own so yield immediately. */ | |
| portYIELD_WITHIN_API(); | |
| } | |
| } | |
| taskEXIT_CRITICAL(); | |
| return pdPASS; | |
| } | |
| else | |
| { | |
| if( xTicksToWait == ( portTickType ) 0 ) | |
| { | |
| taskEXIT_CRITICAL(); | |
| return errQUEUE_FULL; | |
| } | |
| else if( xEntryTimeSet == pdFALSE ) | |
| { | |
| vTaskSetTimeOutState( &xTimeOut ); | |
| xEntryTimeSet = pdTRUE; | |
| } | |
| } | |
| } | |
| taskEXIT_CRITICAL(); | |
| taskENTER_CRITICAL(); | |
| { | |
| if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE ) | |
| { | |
| if( prvIsQueueFull( pxQueue ) != pdFALSE ) | |
| { | |
| traceBLOCKING_ON_QUEUE_SEND( pxQueue ); | |
| vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToSend ), xTicksToWait ); | |
| portYIELD_WITHIN_API(); | |
| } | |
| } | |
| else | |
| { | |
| taskEXIT_CRITICAL(); | |
| traceQUEUE_SEND_FAILED( pxQueue ); | |
| return errQUEUE_FULL; | |
| } | |
| } | |
| taskEXIT_CRITICAL(); | |
| } | |
| } | |
| #endif /* configUSE_ALTERNATIVE_API */ | |
| /*-----------------------------------------------------------*/ | |
| #if configUSE_ALTERNATIVE_API == 1 | |
| signed portBASE_TYPE xQueueAltGenericReceive( xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking ) | |
| { | |
| signed portBASE_TYPE xEntryTimeSet = pdFALSE; | |
| xTimeOutType xTimeOut; | |
| signed char *pcOriginalReadPosition; | |
| configASSERT( pxQueue ); | |
| configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( unsigned portBASE_TYPE ) 0U ) ) ); | |
| for( ;; ) | |
| { | |
| taskENTER_CRITICAL(); | |
| { | |
| if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 ) | |
| { | |
| /* Remember our read position in case we are just peeking. */ | |
| pcOriginalReadPosition = pxQueue->pcReadFrom; | |
| prvCopyDataFromQueue( pxQueue, pvBuffer ); | |
| if( xJustPeeking == pdFALSE ) | |
| { | |
| traceQUEUE_RECEIVE( pxQueue ); | |
| /* We are actually removing data. */ | |
| --( pxQueue->uxMessagesWaiting ); | |
| #if ( configUSE_MUTEXES == 1 ) | |
| { | |
| if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX ) | |
| { | |
| /* Record the information required to implement | |
| priority inheritance should it become necessary. */ | |
| pxQueue->pxMutexHolder = xTaskGetCurrentTaskHandle(); | |
| } | |
| } | |
| #endif | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE ) | |
| { | |
| if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) == pdTRUE ) | |
| { | |
| portYIELD_WITHIN_API(); | |
| } | |
| } | |
| } | |
| else | |
| { | |
| traceQUEUE_PEEK( pxQueue ); | |
| /* We are not removing the data, so reset our read | |
| pointer. */ | |
| pxQueue->pcReadFrom = pcOriginalReadPosition; | |
| /* The data is being left in the queue, so see if there are | |
| any other tasks waiting for the data. */ | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE ) | |
| { | |
| /* Tasks that are removed from the event list will get added to | |
| the pending ready list as the scheduler is still suspended. */ | |
| if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE ) | |
| { | |
| /* The task waiting has a higher priority than this task. */ | |
| portYIELD_WITHIN_API(); | |
| } | |
| } | |
| } | |
| taskEXIT_CRITICAL(); | |
| return pdPASS; | |
| } | |
| else | |
| { | |
| if( xTicksToWait == ( portTickType ) 0 ) | |
| { | |
| taskEXIT_CRITICAL(); | |
| traceQUEUE_RECEIVE_FAILED( pxQueue ); | |
| return errQUEUE_EMPTY; | |
| } | |
| else if( xEntryTimeSet == pdFALSE ) | |
| { | |
| vTaskSetTimeOutState( &xTimeOut ); | |
| xEntryTimeSet = pdTRUE; | |
| } | |
| } | |
| } | |
| taskEXIT_CRITICAL(); | |
| taskENTER_CRITICAL(); | |
| { | |
| if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE ) | |
| { | |
| if( prvIsQueueEmpty( pxQueue ) != pdFALSE ) | |
| { | |
| traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue ); | |
| #if ( configUSE_MUTEXES == 1 ) | |
| { | |
| if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX ) | |
| { | |
| portENTER_CRITICAL(); | |
| vTaskPriorityInherit( ( void * ) pxQueue->pxMutexHolder ); | |
| portEXIT_CRITICAL(); | |
| } | |
| } | |
| #endif | |
| vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait ); | |
| portYIELD_WITHIN_API(); | |
| } | |
| } | |
| else | |
| { | |
| taskEXIT_CRITICAL(); | |
| traceQUEUE_RECEIVE_FAILED( pxQueue ); | |
| return errQUEUE_EMPTY; | |
| } | |
| } | |
| taskEXIT_CRITICAL(); | |
| } | |
| } | |
| #endif /* configUSE_ALTERNATIVE_API */ | |
| /*-----------------------------------------------------------*/ | |
| signed portBASE_TYPE xQueueGenericSendFromISR( xQueueHandle pxQueue, const void * const pvItemToQueue, signed portBASE_TYPE *pxHigherPriorityTaskWoken, portBASE_TYPE xCopyPosition ) | |
| { | |
| signed portBASE_TYPE xReturn; | |
| unsigned portBASE_TYPE uxSavedInterruptStatus; | |
| configASSERT( pxQueue ); | |
| configASSERT( !( ( pvItemToQueue == NULL ) && ( pxQueue->uxItemSize != ( unsigned portBASE_TYPE ) 0U ) ) ); | |
| /* Similar to xQueueGenericSend, except we don't block if there is no room | |
| in the queue. Also we don't directly wake a task that was blocked on a | |
| queue read, instead we return a flag to say whether a context switch is | |
| required or not (i.e. has a task with a higher priority than us been woken | |
| by this post). */ | |
| uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR(); | |
| { | |
| if( pxQueue->uxMessagesWaiting < pxQueue->uxLength ) | |
| { | |
| traceQUEUE_SEND_FROM_ISR( pxQueue ); | |
| prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition ); | |
| /* If the queue is locked we do not alter the event list. This will | |
| be done when the queue is unlocked later. */ | |
| if( pxQueue->xTxLock == queueUNLOCKED ) | |
| { | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE ) | |
| { | |
| if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE ) | |
| { | |
| /* The task waiting has a higher priority so record that a | |
| context switch is required. */ | |
| if( pxHigherPriorityTaskWoken != NULL ) | |
| { | |
| *pxHigherPriorityTaskWoken = pdTRUE; | |
| } | |
| } | |
| } | |
| } | |
| else | |
| { | |
| /* Increment the lock count so the task that unlocks the queue | |
| knows that data was posted while it was locked. */ | |
| ++( pxQueue->xTxLock ); | |
| } | |
| xReturn = pdPASS; | |
| } | |
| else | |
| { | |
| traceQUEUE_SEND_FROM_ISR_FAILED( pxQueue ); | |
| xReturn = errQUEUE_FULL; | |
| } | |
| } | |
| portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus ); | |
| return xReturn; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| signed portBASE_TYPE xQueueGenericReceive( xQueueHandle pxQueue, void * const pvBuffer, portTickType xTicksToWait, portBASE_TYPE xJustPeeking ) | |
| { | |
| signed portBASE_TYPE xEntryTimeSet = pdFALSE; | |
| xTimeOutType xTimeOut; | |
| signed char *pcOriginalReadPosition; | |
| configASSERT( pxQueue ); | |
| configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( unsigned portBASE_TYPE ) 0U ) ) ); | |
| /* This function relaxes the coding standard somewhat to allow return | |
| statements within the function itself. This is done in the interest | |
| of execution time efficiency. */ | |
| for( ;; ) | |
| { | |
| taskENTER_CRITICAL(); | |
| { | |
| /* Is there data in the queue now? To be running we must be | |
| the highest priority task wanting to access the queue. */ | |
| if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 ) | |
| { | |
| /* Remember our read position in case we are just peeking. */ | |
| pcOriginalReadPosition = pxQueue->pcReadFrom; | |
| prvCopyDataFromQueue( pxQueue, pvBuffer ); | |
| if( xJustPeeking == pdFALSE ) | |
| { | |
| traceQUEUE_RECEIVE( pxQueue ); | |
| /* We are actually removing data. */ | |
| --( pxQueue->uxMessagesWaiting ); | |
| #if ( configUSE_MUTEXES == 1 ) | |
| { | |
| if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX ) | |
| { | |
| /* Record the information required to implement | |
| priority inheritance should it become necessary. */ | |
| pxQueue->pxMutexHolder = xTaskGetCurrentTaskHandle(); | |
| } | |
| } | |
| #endif | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE ) | |
| { | |
| if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) == pdTRUE ) | |
| { | |
| portYIELD_WITHIN_API(); | |
| } | |
| } | |
| } | |
| else | |
| { | |
| traceQUEUE_PEEK( pxQueue ); | |
| /* We are not removing the data, so reset our read | |
| pointer. */ | |
| pxQueue->pcReadFrom = pcOriginalReadPosition; | |
| /* The data is being left in the queue, so see if there are | |
| any other tasks waiting for the data. */ | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE ) | |
| { | |
| /* Tasks that are removed from the event list will get added to | |
| the pending ready list as the scheduler is still suspended. */ | |
| if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE ) | |
| { | |
| /* The task waiting has a higher priority than this task. */ | |
| portYIELD_WITHIN_API(); | |
| } | |
| } | |
| } | |
| taskEXIT_CRITICAL(); | |
| return pdPASS; | |
| } | |
| else | |
| { | |
| if( xTicksToWait == ( portTickType ) 0 ) | |
| { | |
| /* The queue was empty and no block time is specified (or | |
| the block time has expired) so leave now. */ | |
| taskEXIT_CRITICAL(); | |
| traceQUEUE_RECEIVE_FAILED( pxQueue ); | |
| return errQUEUE_EMPTY; | |
| } | |
| else if( xEntryTimeSet == pdFALSE ) | |
| { | |
| /* The queue was empty and a block time was specified so | |
| configure the timeout structure. */ | |
| vTaskSetTimeOutState( &xTimeOut ); | |
| xEntryTimeSet = pdTRUE; | |
| } | |
| } | |
| } | |
| taskEXIT_CRITICAL(); | |
| /* Interrupts and other tasks can send to and receive from the queue | |
| now the critical section has been exited. */ | |
| vTaskSuspendAll(); | |
| prvLockQueue( pxQueue ); | |
| /* Update the timeout state to see if it has expired yet. */ | |
| if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE ) | |
| { | |
| if( prvIsQueueEmpty( pxQueue ) != pdFALSE ) | |
| { | |
| traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue ); | |
| #if ( configUSE_MUTEXES == 1 ) | |
| { | |
| if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX ) | |
| { | |
| portENTER_CRITICAL(); | |
| { | |
| vTaskPriorityInherit( ( void * ) pxQueue->pxMutexHolder ); | |
| } | |
| portEXIT_CRITICAL(); | |
| } | |
| } | |
| #endif | |
| vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait ); | |
| prvUnlockQueue( pxQueue ); | |
| if( xTaskResumeAll() == pdFALSE ) | |
| { | |
| portYIELD_WITHIN_API(); | |
| } | |
| } | |
| else | |
| { | |
| /* Try again. */ | |
| prvUnlockQueue( pxQueue ); | |
| ( void ) xTaskResumeAll(); | |
| } | |
| } | |
| else | |
| { | |
| prvUnlockQueue( pxQueue ); | |
| ( void ) xTaskResumeAll(); | |
| traceQUEUE_RECEIVE_FAILED( pxQueue ); | |
| return errQUEUE_EMPTY; | |
| } | |
| } | |
| } | |
| /*-----------------------------------------------------------*/ | |
| signed portBASE_TYPE xQueueReceiveFromISR( xQueueHandle pxQueue, void * const pvBuffer, signed portBASE_TYPE *pxHigherPriorityTaskWoken ) | |
| { | |
| signed portBASE_TYPE xReturn; | |
| unsigned portBASE_TYPE uxSavedInterruptStatus; | |
| configASSERT( pxQueue ); | |
| configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( unsigned portBASE_TYPE ) 0U ) ) ); | |
| uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR(); | |
| { | |
| /* We cannot block from an ISR, so check there is data available. */ | |
| if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 ) | |
| { | |
| traceQUEUE_RECEIVE_FROM_ISR( pxQueue ); | |
| prvCopyDataFromQueue( pxQueue, pvBuffer ); | |
| --( pxQueue->uxMessagesWaiting ); | |
| /* If the queue is locked we will not modify the event list. Instead | |
| we update the lock count so the task that unlocks the queue will know | |
| that an ISR has removed data while the queue was locked. */ | |
| if( pxQueue->xRxLock == queueUNLOCKED ) | |
| { | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE ) | |
| { | |
| if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE ) | |
| { | |
| /* The task waiting has a higher priority than us so | |
| force a context switch. */ | |
| if( pxHigherPriorityTaskWoken != NULL ) | |
| { | |
| *pxHigherPriorityTaskWoken = pdTRUE; | |
| } | |
| } | |
| } | |
| } | |
| else | |
| { | |
| /* Increment the lock count so the task that unlocks the queue | |
| knows that data was removed while it was locked. */ | |
| ++( pxQueue->xRxLock ); | |
| } | |
| xReturn = pdPASS; | |
| } | |
| else | |
| { | |
| xReturn = pdFAIL; | |
| traceQUEUE_RECEIVE_FROM_ISR_FAILED( pxQueue ); | |
| } | |
| } | |
| portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus ); | |
| return xReturn; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| unsigned portBASE_TYPE uxQueueMessagesWaiting( const xQueueHandle pxQueue ) | |
| { | |
| unsigned portBASE_TYPE uxReturn; | |
| configASSERT( pxQueue ); | |
| taskENTER_CRITICAL(); | |
| uxReturn = pxQueue->uxMessagesWaiting; | |
| taskEXIT_CRITICAL(); | |
| return uxReturn; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| unsigned portBASE_TYPE uxQueueMessagesWaitingFromISR( const xQueueHandle pxQueue ) | |
| { | |
| unsigned portBASE_TYPE uxReturn; | |
| configASSERT( pxQueue ); | |
| uxReturn = pxQueue->uxMessagesWaiting; | |
| return uxReturn; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| void vQueueDelete( xQueueHandle pxQueue ) | |
| { | |
| configASSERT( pxQueue ); | |
| traceQUEUE_DELETE( pxQueue ); | |
| vQueueUnregisterQueue( pxQueue ); | |
| if((pxQueue->ucQueueType == queueQUEUE_TYPE_BINARY_SEMAPHORE) | |
| || (pxQueue->ucQueueType == queueQUEUE_TYPE_COUNTING_SEMAPHORE)) | |
| { | |
| poolFreeBuffer( &sSemaphoresPool, pxQueue->pcHead); | |
| } | |
| poolFreeBuffer( &sQueuesPool, pxQueue ); | |
| } | |
| /*-----------------------------------------------------------*/ | |
| #if ( configUSE_TRACE_FACILITY == 1 ) | |
| unsigned char ucQueueGetQueueNumber( xQueueHandle pxQueue ) | |
| { | |
| return pxQueue->ucQueueNumber; | |
| } | |
| #endif | |
| /*-----------------------------------------------------------*/ | |
| #if ( configUSE_TRACE_FACILITY == 1 ) | |
| void vQueueSetQueueNumber( xQueueHandle pxQueue, unsigned char ucQueueNumber ) | |
| { | |
| pxQueue->ucQueueNumber = ucQueueNumber; | |
| } | |
| #endif | |
| /*-----------------------------------------------------------*/ | |
| #if ( configUSE_TRACE_FACILITY == 1 ) | |
| unsigned char ucQueueGetQueueType( xQueueHandle pxQueue ) | |
| { | |
| return pxQueue->ucQueueType; | |
| } | |
| #endif | |
| /*-----------------------------------------------------------*/ | |
| static void prvCopyDataToQueue( xQUEUE *pxQueue, const void *pvItemToQueue, portBASE_TYPE xPosition ) | |
| { | |
| if( pxQueue->uxItemSize == ( unsigned portBASE_TYPE ) 0 ) | |
| { | |
| #if ( configUSE_MUTEXES == 1 ) | |
| { | |
| if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX ) | |
| { | |
| /* The mutex is no longer being held. */ | |
| vTaskPriorityDisinherit( ( void * ) pxQueue->pxMutexHolder ); | |
| pxQueue->pxMutexHolder = NULL; | |
| } | |
| } | |
| #endif | |
| } | |
| else if( xPosition == queueSEND_TO_BACK ) | |
| { | |
| memcpy( ( void * ) pxQueue->pcWriteTo, pvItemToQueue, ( unsigned ) pxQueue->uxItemSize ); | |
| pxQueue->pcWriteTo += pxQueue->uxItemSize; | |
| if( pxQueue->pcWriteTo >= pxQueue->pcTail ) | |
| { | |
| pxQueue->pcWriteTo = pxQueue->pcHead; | |
| } | |
| } | |
| else | |
| { | |
| memcpy( ( void * ) pxQueue->pcReadFrom, pvItemToQueue, ( unsigned ) pxQueue->uxItemSize ); | |
| pxQueue->pcReadFrom -= pxQueue->uxItemSize; | |
| if( pxQueue->pcReadFrom < pxQueue->pcHead ) | |
| { | |
| pxQueue->pcReadFrom = ( pxQueue->pcTail - pxQueue->uxItemSize ); | |
| } | |
| } | |
| ++( pxQueue->uxMessagesWaiting ); | |
| } | |
| /*-----------------------------------------------------------*/ | |
| static void prvCopyDataFromQueue( xQUEUE * const pxQueue, const void *pvBuffer ) | |
| { | |
| if( pxQueue->uxQueueType != queueQUEUE_IS_MUTEX ) | |
| { | |
| pxQueue->pcReadFrom += pxQueue->uxItemSize; | |
| if( pxQueue->pcReadFrom >= pxQueue->pcTail ) | |
| { | |
| pxQueue->pcReadFrom = pxQueue->pcHead; | |
| } | |
| memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->pcReadFrom, ( unsigned ) pxQueue->uxItemSize ); | |
| } | |
| } | |
| /*-----------------------------------------------------------*/ | |
| static void prvUnlockQueue( xQueueHandle pxQueue ) | |
| { | |
| /* THIS FUNCTION MUST BE CALLED WITH THE SCHEDULER SUSPENDED. */ | |
| /* The lock counts contains the number of extra data items placed or | |
| removed from the queue while the queue was locked. When a queue is | |
| locked items can be added or removed, but the event lists cannot be | |
| updated. */ | |
| taskENTER_CRITICAL(); | |
| { | |
| /* See if data was added to the queue while it was locked. */ | |
| while( pxQueue->xTxLock > queueLOCKED_UNMODIFIED ) | |
| { | |
| /* Data was posted while the queue was locked. Are any tasks | |
| blocked waiting for data to become available? */ | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE ) | |
| { | |
| /* Tasks that are removed from the event list will get added to | |
| the pending ready list as the scheduler is still suspended. */ | |
| if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE ) | |
| { | |
| /* The task waiting has a higher priority so record that a | |
| context switch is required. */ | |
| vTaskMissedYield(); | |
| } | |
| --( pxQueue->xTxLock ); | |
| } | |
| else | |
| { | |
| break; | |
| } | |
| } | |
| pxQueue->xTxLock = queueUNLOCKED; | |
| } | |
| taskEXIT_CRITICAL(); | |
| /* Do the same for the Rx lock. */ | |
| taskENTER_CRITICAL(); | |
| { | |
| while( pxQueue->xRxLock > queueLOCKED_UNMODIFIED ) | |
| { | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE ) | |
| { | |
| if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE ) | |
| { | |
| vTaskMissedYield(); | |
| } | |
| --( pxQueue->xRxLock ); | |
| } | |
| else | |
| { | |
| break; | |
| } | |
| } | |
| pxQueue->xRxLock = queueUNLOCKED; | |
| } | |
| taskEXIT_CRITICAL(); | |
| } | |
| /*-----------------------------------------------------------*/ | |
| static signed portBASE_TYPE prvIsQueueEmpty( const xQueueHandle pxQueue ) | |
| { | |
| signed portBASE_TYPE xReturn; | |
| taskENTER_CRITICAL(); | |
| xReturn = ( pxQueue->uxMessagesWaiting == ( unsigned portBASE_TYPE ) 0 ); | |
| taskEXIT_CRITICAL(); | |
| return xReturn; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| signed portBASE_TYPE xQueueIsQueueEmptyFromISR( const xQueueHandle pxQueue ) | |
| { | |
| signed portBASE_TYPE xReturn; | |
| configASSERT( pxQueue ); | |
| xReturn = ( pxQueue->uxMessagesWaiting == ( unsigned portBASE_TYPE ) 0 ); | |
| return xReturn; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| static signed portBASE_TYPE prvIsQueueFull( const xQueueHandle pxQueue ) | |
| { | |
| signed portBASE_TYPE xReturn; | |
| taskENTER_CRITICAL(); | |
| xReturn = ( pxQueue->uxMessagesWaiting == pxQueue->uxLength ); | |
| taskEXIT_CRITICAL(); | |
| return xReturn; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| signed portBASE_TYPE xQueueIsQueueFullFromISR( const xQueueHandle pxQueue ) | |
| { | |
| signed portBASE_TYPE xReturn; | |
| configASSERT( pxQueue ); | |
| xReturn = ( pxQueue->uxMessagesWaiting == pxQueue->uxLength ); | |
| return xReturn; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| #if configUSE_CO_ROUTINES == 1 | |
| signed portBASE_TYPE xQueueCRSend( xQueueHandle pxQueue, const void *pvItemToQueue, portTickType xTicksToWait ) | |
| { | |
| signed portBASE_TYPE xReturn; | |
| /* If the queue is already full we may have to block. A critical section | |
| is required to prevent an interrupt removing something from the queue | |
| between the check to see if the queue is full and blocking on the queue. */ | |
| portDISABLE_INTERRUPTS(); | |
| { | |
| if( prvIsQueueFull( pxQueue ) != pdFALSE ) | |
| { | |
| /* The queue is full - do we want to block or just leave without | |
| posting? */ | |
| if( xTicksToWait > ( portTickType ) 0 ) | |
| { | |
| /* As this is called from a coroutine we cannot block directly, but | |
| return indicating that we need to block. */ | |
| vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToSend ) ); | |
| portENABLE_INTERRUPTS(); | |
| return errQUEUE_BLOCKED; | |
| } | |
| else | |
| { | |
| portENABLE_INTERRUPTS(); | |
| return errQUEUE_FULL; | |
| } | |
| } | |
| } | |
| portENABLE_INTERRUPTS(); | |
| portNOP(); | |
| portDISABLE_INTERRUPTS(); | |
| { | |
| if( pxQueue->uxMessagesWaiting < pxQueue->uxLength ) | |
| { | |
| /* There is room in the queue, copy the data into the queue. */ | |
| prvCopyDataToQueue( pxQueue, pvItemToQueue, queueSEND_TO_BACK ); | |
| xReturn = pdPASS; | |
| /* Were any co-routines waiting for data to become available? */ | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE ) | |
| { | |
| /* In this instance the co-routine could be placed directly | |
| into the ready list as we are within a critical section. | |
| Instead the same pending ready list mechanism is used as if | |
| the event were caused from within an interrupt. */ | |
| if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE ) | |
| { | |
| /* The co-routine waiting has a higher priority so record | |
| that a yield might be appropriate. */ | |
| xReturn = errQUEUE_YIELD; | |
| } | |
| } | |
| } | |
| else | |
| { | |
| xReturn = errQUEUE_FULL; | |
| } | |
| } | |
| portENABLE_INTERRUPTS(); | |
| return xReturn; | |
| } | |
| #endif | |
| /*-----------------------------------------------------------*/ | |
| #if configUSE_CO_ROUTINES == 1 | |
| signed portBASE_TYPE xQueueCRReceive( xQueueHandle pxQueue, void *pvBuffer, portTickType xTicksToWait ) | |
| { | |
| signed portBASE_TYPE xReturn; | |
| /* If the queue is already empty we may have to block. A critical section | |
| is required to prevent an interrupt adding something to the queue | |
| between the check to see if the queue is empty and blocking on the queue. */ | |
| portDISABLE_INTERRUPTS(); | |
| { | |
| if( pxQueue->uxMessagesWaiting == ( unsigned portBASE_TYPE ) 0 ) | |
| { | |
| /* There are no messages in the queue, do we want to block or just | |
| leave with nothing? */ | |
| if( xTicksToWait > ( portTickType ) 0 ) | |
| { | |
| /* As this is a co-routine we cannot block directly, but return | |
| indicating that we need to block. */ | |
| vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToReceive ) ); | |
| portENABLE_INTERRUPTS(); | |
| return errQUEUE_BLOCKED; | |
| } | |
| else | |
| { | |
| portENABLE_INTERRUPTS(); | |
| return errQUEUE_FULL; | |
| } | |
| } | |
| } | |
| portENABLE_INTERRUPTS(); | |
| portNOP(); | |
| portDISABLE_INTERRUPTS(); | |
| { | |
| if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 ) | |
| { | |
| /* Data is available from the queue. */ | |
| pxQueue->pcReadFrom += pxQueue->uxItemSize; | |
| if( pxQueue->pcReadFrom >= pxQueue->pcTail ) | |
| { | |
| pxQueue->pcReadFrom = pxQueue->pcHead; | |
| } | |
| --( pxQueue->uxMessagesWaiting ); | |
| memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->pcReadFrom, ( unsigned ) pxQueue->uxItemSize ); | |
| xReturn = pdPASS; | |
| /* Were any co-routines waiting for space to become available? */ | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE ) | |
| { | |
| /* In this instance the co-routine could be placed directly | |
| into the ready list as we are within a critical section. | |
| Instead the same pending ready list mechanism is used as if | |
| the event were caused from within an interrupt. */ | |
| if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE ) | |
| { | |
| xReturn = errQUEUE_YIELD; | |
| } | |
| } | |
| } | |
| else | |
| { | |
| xReturn = pdFAIL; | |
| } | |
| } | |
| portENABLE_INTERRUPTS(); | |
| return xReturn; | |
| } | |
| #endif | |
| /*-----------------------------------------------------------*/ | |
| #if configUSE_CO_ROUTINES == 1 | |
| signed portBASE_TYPE xQueueCRSendFromISR( xQueueHandle pxQueue, const void *pvItemToQueue, signed portBASE_TYPE xCoRoutinePreviouslyWoken ) | |
| { | |
| /* Cannot block within an ISR so if there is no space on the queue then | |
| exit without doing anything. */ | |
| if( pxQueue->uxMessagesWaiting < pxQueue->uxLength ) | |
| { | |
| prvCopyDataToQueue( pxQueue, pvItemToQueue, queueSEND_TO_BACK ); | |
| /* We only want to wake one co-routine per ISR, so check that a | |
| co-routine has not already been woken. */ | |
| if( xCoRoutinePreviouslyWoken == pdFALSE ) | |
| { | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE ) | |
| { | |
| if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE ) | |
| { | |
| return pdTRUE; | |
| } | |
| } | |
| } | |
| } | |
| return xCoRoutinePreviouslyWoken; | |
| } | |
| #endif | |
| /*-----------------------------------------------------------*/ | |
| #if configUSE_CO_ROUTINES == 1 | |
| signed portBASE_TYPE xQueueCRReceiveFromISR( xQueueHandle pxQueue, void *pvBuffer, signed portBASE_TYPE *pxCoRoutineWoken ) | |
| { | |
| signed portBASE_TYPE xReturn; | |
| /* We cannot block from an ISR, so check there is data available. If | |
| not then just leave without doing anything. */ | |
| if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 ) | |
| { | |
| /* Copy the data from the queue. */ | |
| pxQueue->pcReadFrom += pxQueue->uxItemSize; | |
| if( pxQueue->pcReadFrom >= pxQueue->pcTail ) | |
| { | |
| pxQueue->pcReadFrom = pxQueue->pcHead; | |
| } | |
| --( pxQueue->uxMessagesWaiting ); | |
| memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->pcReadFrom, ( unsigned ) pxQueue->uxItemSize ); | |
| if( ( *pxCoRoutineWoken ) == pdFALSE ) | |
| { | |
| if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE ) | |
| { | |
| if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE ) | |
| { | |
| *pxCoRoutineWoken = pdTRUE; | |
| } | |
| } | |
| } | |
| xReturn = pdPASS; | |
| } | |
| else | |
| { | |
| xReturn = pdFAIL; | |
| } | |
| return xReturn; | |
| } | |
| #endif | |
| /*-----------------------------------------------------------*/ | |
| #if configQUEUE_REGISTRY_SIZE > 0 | |
| void vQueueAddToRegistry( xQueueHandle xQueue, signed char *pcQueueName ) | |
| { | |
| unsigned portBASE_TYPE ux; | |
| /* See if there is an empty space in the registry. A NULL name denotes | |
| a free slot. */ | |
| for( ux = ( unsigned portBASE_TYPE ) 0U; ux < ( unsigned portBASE_TYPE ) configQUEUE_REGISTRY_SIZE; ux++ ) | |
| { | |
| if( xQueueRegistry[ ux ].pcQueueName == NULL ) | |
| { | |
| /* Store the information on this queue. */ | |
| xQueueRegistry[ ux ].pcQueueName = pcQueueName; | |
| xQueueRegistry[ ux ].xHandle = xQueue; | |
| break; | |
| } | |
| } | |
| } | |
| #endif | |
| /*-----------------------------------------------------------*/ | |
| #if configQUEUE_REGISTRY_SIZE > 0 | |
| static void vQueueUnregisterQueue( xQueueHandle xQueue ) | |
| { | |
| unsigned portBASE_TYPE ux; | |
| /* See if the handle of the queue being unregistered in actually in the | |
| registry. */ | |
| for( ux = ( unsigned portBASE_TYPE ) 0U; ux < ( unsigned portBASE_TYPE ) configQUEUE_REGISTRY_SIZE; ux++ ) | |
| { | |
| if( xQueueRegistry[ ux ].xHandle == xQueue ) | |
| { | |
| /* Set the name to NULL to show that this slot if free again. */ | |
| xQueueRegistry[ ux ].pcQueueName = NULL; | |
| break; | |
| } | |
| } | |
| } | |
| #endif | |
| /*-----------------------------------------------------------*/ | |
| #if configUSE_TIMERS == 1 | |
| void vQueueWaitForMessageRestricted( xQueueHandle pxQueue, portTickType xTicksToWait ) | |
| { | |
| /* This function should not be called by application code hence the | |
| 'Restricted' in its name. It is not part of the public API. It is | |
| designed for use by kernel code, and has special calling requirements. | |
| It can result in vListInsert() being called on a list that can only | |
| possibly ever have one item in it, so the list will be fast, but even | |
| so it should be called with the scheduler locked and not from a critical | |
| section. */ | |
| /* Only do anything if there are no messages in the queue. This function | |
| will not actually cause the task to block, just place it on a blocked | |
| list. It will not block until the scheduler is unlocked - at which | |
| time a yield will be performed. If an item is added to the queue while | |
| the queue is locked, and the calling task blocks on the queue, then the | |
| calling task will be immediately unblocked when the queue is unlocked. */ | |
| prvLockQueue( pxQueue ); | |
| if( pxQueue->uxMessagesWaiting == ( unsigned portBASE_TYPE ) 0U ) | |
| { | |
| /* There is nothing in the queue, block for the specified period. */ | |
| vTaskPlaceOnEventListRestricted( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait ); | |
| } | |
| prvUnlockQueue( pxQueue ); | |
| } | |
| #endif | |