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Diffstat (limited to 'libraries/FreeRTOS/utility/queue.c')
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1 files changed, 1539 insertions, 0 deletions
diff --git a/libraries/FreeRTOS/utility/queue.c b/libraries/FreeRTOS/utility/queue.c new file mode 100755 index 0000000..c7ed600 --- /dev/null +++ b/libraries/FreeRTOS/utility/queue.c @@ -0,0 +1,1539 @@ +/* + FreeRTOS V7.0.1 - Copyright (C) 2011 Real Time Engineers Ltd. + + + FreeRTOS supports many tools and architectures. V7.0.0 is sponsored by: + Atollic AB - Atollic provides professional embedded systems development + tools for C/C++ development, code analysis and test automation. + See http://www.atollic.com + + + *************************************************************************** + * * + * 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! + + http://www.FreeRTOS.org - Documentation, latest information, license and + contact details. + + http://www.SafeRTOS.com - A version that is certified for use in safety + critical systems. + + http://www.OpenRTOS.com - Commercial support, development, porting, + licensing and training services. +*/ + +#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 "croutine.h" + +#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE + +/*----------------------------------------------------------- + * PUBLIC LIST API documented in list.h + *----------------------------------------------------------*/ + +/* Constants used with the cRxLock and cTxLock 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 ( 0 ) +#define queueDONT_BLOCK ( ( portTickType ) 0 ) +#define queueMUTEX_GIVE_BLOCK_TIME ( ( portTickType ) 0 ) + +/* + * 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. */ + + 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. */ + 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. */ + +} 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. + */ +xQueueHandle xQueueCreate( unsigned portBASE_TYPE uxQueueLength, unsigned portBASE_TYPE uxItemSize ) PRIVILEGED_FUNCTION; +signed portBASE_TYPE xQueueGenericSend( xQueueHandle xQueue, 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 *pxTaskWoken ) PRIVILEGED_FUNCTION; +xQueueHandle xQueueCreateMutex( void ) 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; + +/* + * 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 + +/* + * 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 + *----------------------------------------------------------*/ + +xQueueHandle xQueueCreate( unsigned portBASE_TYPE uxQueueLength, unsigned portBASE_TYPE uxItemSize ) +{ +xQUEUE *pxNewQueue; +size_t xQueueSizeInBytes; +xQueueHandle xReturn = NULL; + + /* Allocate the new queue structure. */ + if( uxQueueLength > ( unsigned portBASE_TYPE ) 0 ) + { + pxNewQueue = ( xQUEUE * ) pvPortMalloc( sizeof( xQUEUE ) ); + if( pxNewQueue != NULL ) + { + /* Create the list of pointers to queue items. The queue is one byte + longer than asked for to make wrap checking easier/faster. */ + xQueueSizeInBytes = ( size_t ) ( uxQueueLength * uxItemSize ) + ( size_t ) 1; + + pxNewQueue->pcHead = ( signed char * ) pvPortMalloc( xQueueSizeInBytes ); + if( pxNewQueue->pcHead != NULL ) + { + /* Initialise the queue members as described above where the + queue type is defined. */ + pxNewQueue->pcTail = pxNewQueue->pcHead + ( uxQueueLength * uxItemSize ); + pxNewQueue->uxMessagesWaiting = ( unsigned portBASE_TYPE ) 0U; + pxNewQueue->pcWriteTo = pxNewQueue->pcHead; + pxNewQueue->pcReadFrom = pxNewQueue->pcHead + ( ( uxQueueLength - ( unsigned portBASE_TYPE ) 1U ) * uxItemSize ); + pxNewQueue->uxLength = uxQueueLength; + pxNewQueue->uxItemSize = uxItemSize; + pxNewQueue->xRxLock = queueUNLOCKED; + pxNewQueue->xTxLock = queueUNLOCKED; + + /* Likewise ensure the event queues start with the correct state. */ + vListInitialise( &( pxNewQueue->xTasksWaitingToSend ) ); + vListInitialise( &( pxNewQueue->xTasksWaitingToReceive ) ); + + traceQUEUE_CREATE( pxNewQueue ); + xReturn = pxNewQueue; + } + else + { + traceQUEUE_CREATE_FAILED(); + vPortFree( pxNewQueue ); + } + } + } + + configASSERT( xReturn ); + + return xReturn; +} +/*-----------------------------------------------------------*/ + +#if ( configUSE_MUTEXES == 1 ) + + xQueueHandle xQueueCreateMutex( void ) + { + xQUEUE *pxNewQueue; + + /* Allocate the new queue structure. */ + pxNewQueue = ( xQUEUE * ) pvPortMalloc( sizeof( xQUEUE ) ); + 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; + + /* Ensure the event queues start with the correct state. */ + vListInitialise( &( pxNewQueue->xTasksWaitingToSend ) ); + vListInitialise( &( pxNewQueue->xTasksWaitingToReceive ) ); + + /* Start with the semaphore in the expected state. */ + xQueueGenericSend( pxNewQueue, NULL, ( portTickType ) 0U, queueSEND_TO_BACK ); + + traceCREATE_MUTEX( pxNewQueue ); + } + else + { + traceCREATE_MUTEX_FAILED(); + } + + configASSERT( pxNewQueue ); + return pxNewQueue; + } + +#endif /* configUSE_MUTEXES */ +/*-----------------------------------------------------------*/ + +#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 )--; + + /* Have we unwound the call count? */ + if( pxMutex->uxRecursiveCallCount == 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; + + pxHandle = xQueueCreate( ( unsigned portBASE_TYPE ) uxCountValue, queueSEMAPHORE_QUEUE_ITEM_LENGTH ); + + 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 ) ) + { + 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() ) + { + 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 ) ) + { + 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 ) ) + { + 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( pxHigherPriorityTaskWoken ); + 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. */ + *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 ) ) + { + 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() ) + { + 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 *pxTaskWoken ) +{ +signed portBASE_TYPE xReturn; +unsigned portBASE_TYPE uxSavedInterruptStatus; + + configASSERT( pxQueue ); + configASSERT( pxTaskWoken ); + 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. */ + *pxTaskWoken = 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 ); + vPortFree( pxQueue->pcHead ); + vPortFree( pxQueue ); +} +/*-----------------------------------------------------------*/ + +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 ) ) + { + /* 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 ) + { + 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 ) ) + { + 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 < 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 < 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 + |