Add event_groups.c and associated functions in other core files.
Added xTimerPendCallbackFromISR() to provide a centralised deferred interrupt handling mechanism. Add xPortGetLowestEverFreeHeapSize() to heap_4.c.pull/1/head
parent
faed443e82
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/*
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FreeRTOS V7.6.0 - Copyright (C) 2013 Real Time Engineers Ltd.
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All rights reserved
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VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
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***************************************************************************
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* *
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* FreeRTOS provides completely free yet professionally developed, *
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* robust, strictly quality controlled, supported, and cross *
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* platform software that has become a de facto standard. *
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* *
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* Help yourself get started quickly and support the FreeRTOS *
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* project by purchasing a FreeRTOS tutorial book, reference *
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* manual, or both from: http://www.FreeRTOS.org/Documentation *
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* *
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* Thank you! *
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* *
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***************************************************************************
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This file is part of the FreeRTOS distribution.
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FreeRTOS is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License (version 2) as published by the
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Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception.
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>>! NOTE: The modification to the GPL is included to allow you to distribute
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>>! a combined work that includes FreeRTOS without being obliged to provide
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>>! the source code for proprietary components outside of the FreeRTOS
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>>! kernel.
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FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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FOR A PARTICULAR PURPOSE. Full license text is available from the following
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link: http://www.freertos.org/a00114.html
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1 tab == 4 spaces!
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***************************************************************************
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* *
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* Having a problem? Start by reading the FAQ "My application does *
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* not run, what could be wrong?" *
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* *
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* http://www.FreeRTOS.org/FAQHelp.html *
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* *
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***************************************************************************
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http://www.FreeRTOS.org - Documentation, books, training, latest versions,
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license and Real Time Engineers Ltd. contact details.
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http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
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including FreeRTOS+Trace - an indispensable productivity tool, a DOS
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||||
compatible FAT file system, and our tiny thread aware UDP/IP stack.
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||||
|
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http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
|
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Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS
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||||
licenses offer ticketed support, indemnification and middleware.
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||||
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http://www.SafeRTOS.com - High Integrity Systems also provide a safety
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engineered and independently SIL3 certified version for use in safety and
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mission critical applications that require provable dependability.
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1 tab == 4 spaces!
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*/
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/* Standard includes. */
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#include <stdlib.h>
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/* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
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all the API functions to use the MPU wrappers. That should only be done when
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task.h is included from an application file. */
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#define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
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/* FreeRTOS includes. */
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#include "FreeRTOS.h"
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#include "task.h"
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#include "timers.h"
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#include "event_groups.h"
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/* Lint e961 and e750 are suppressed as a MISRA exception justified because the
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MPU ports require MPU_WRAPPERS_INCLUDED_FROM_API_FILE to be defined for the
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header files above, but not in this file, in order to generate the correct
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privileged Vs unprivileged linkage and placement. */
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#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE /*lint !e961 !e750. */
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#if ( INCLUDE_xEventGroupSetBitFromISR == 1 ) && ( configUSE_TIMERS == 0 )
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#error configUSE_TIMERS must be set to 1 to make the xEventGroupSetBitFromISR() function available.
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#endif
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#if ( INCLUDE_xEventGroupSetBitFromISR == 1 ) && ( INCLUDE_xTimerPendCallbackFromISR == 0 )
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#error INCLUDE_xTimerPendCallbackFromISR must also be set to one to make the xEventGroupSetBitFromISR() function available.
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#endif
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#if configUSE_16_BIT_TICKS == 1
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#define taskCLEAR_EVENTS_ON_EXIT_BIT 0x0100U
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#define taskUNBLOCKED_DUE_TO_BIT_SET_BIT 0x0200U
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#define taskWAIT_FOR_ALL_BITS 0x0400U
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#define taskEVENT_BITS_CONTROL_BYTES 0xff00U
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#else
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#define taskCLEAR_EVENTS_ON_EXIT_BIT 0x01000000UL
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#define taskUNBLOCKED_DUE_TO_BIT_SET_BIT 0x02000000UL
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#define taskWAIT_FOR_ALL_BITS 0x04000000UL
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#define taskEVENT_BITS_CONTROL_BYTES 0xff000000UL
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#endif
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typedef struct EventBitsDefinition
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{
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xEventBitsType uxEventBits;
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xList xTasksWaitingForBits; /*< List of tasks waiting for a bit to be set. */
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} xEVENT_BITS;
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/* Used internally only. */
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typedef struct EVENT_GROUP_CALLBACK_PARAMTERS
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{
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xEventGroupHandle xTargetEventGroup;
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xEventBitsType xBitsToSet;
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} xEventGroupCallbackParameters;
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/*-----------------------------------------------------------*/
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xEventGroupHandle xEventGroupCreate( void )
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{
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xEVENT_BITS *pxEventBits;
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pxEventBits = pvPortMalloc( sizeof( xEVENT_BITS ) );
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if( pxEventBits != NULL )
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{
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pxEventBits->uxEventBits = 0;
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vListInitialise( &( pxEventBits->xTasksWaitingForBits ) );
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}
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return ( xEventGroupHandle ) pxEventBits;
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}
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/*-----------------------------------------------------------*/
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xEventBitsType xEventGroupSync( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToSet, xEventBitsType uxBitsToWaitFor, portTickType xBlockTime )
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{
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xEventBitsType uxOriginalBitValue, uxReturn;
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xEVENT_BITS *pxEventBits = ( xEVENT_BITS * ) xEventGroup;
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portBASE_TYPE xYieldedAlready;
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vTaskSuspendAll();
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{
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uxOriginalBitValue = pxEventBits->uxEventBits;
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( void ) xEventGroupSetBits( xEventGroup, uxBitsToSet );
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if( ( ( uxOriginalBitValue | uxBitsToSet ) & uxBitsToWaitFor ) == uxBitsToWaitFor )
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{
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/* All the rendezvous bits will have been set once this task set
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its bits - no need to block. */
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uxReturn = ( uxOriginalBitValue | uxBitsToSet );
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/* Rendezvous always clear the bits. They will have been cleared
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already unless this is the only task in the rendezvous. */
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pxEventBits->uxEventBits &= uxBitsToWaitFor;
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xBlockTime = 0;
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}
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else
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{
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if( xBlockTime != ( portTickType ) 0 )
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{
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/* Store the bits that the calling task is waiting for in the
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task's event list item so the kernel knows when a match is
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found. Then enter the blocked state. */
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vTaskPlaceOnUnorderedEventList( &( pxEventBits->xTasksWaitingForBits ), ( uxBitsToWaitFor | taskCLEAR_EVENTS_ON_EXIT_BIT | taskWAIT_FOR_ALL_BITS ), xBlockTime );
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}
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else
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{
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/* The rendezvous bits were not set, but no block time was
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specified - just return the current event bit value. */
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uxReturn = pxEventBits->uxEventBits;
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}
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}
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}
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xYieldedAlready = xTaskResumeAll();
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if( xBlockTime != ( portTickType ) 0 )
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{
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if( xYieldedAlready == pdFALSE )
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{
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portYIELD_WITHIN_API();
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}
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/* The task blocked to wait for its required bits to be set - at this
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point either the required bits were set or the block time expired. If
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the required bits were set they will have been stored in the task's
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event list item, and they should now be retrieved then cleared. */
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uxReturn = uxTaskResetEventItemValue();
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if( ( uxReturn & taskUNBLOCKED_DUE_TO_BIT_SET_BIT ) == ( xEventBitsType ) 0 )
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{
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/* The task timed out, just return the current event bit value. */
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uxReturn = pxEventBits->uxEventBits;
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}
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else
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{
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/* The task unblocked because the bits were set. Clear the control
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bits before returning the value. */
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uxReturn &= ~taskEVENT_BITS_CONTROL_BYTES;
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}
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}
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return uxReturn;
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}
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/*-----------------------------------------------------------*/
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xEventBitsType xEventGroupWaitBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToWaitFor, portBASE_TYPE xClearOnExit, portBASE_TYPE xWaitForAllBits, portTickType xBlockTime )
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{
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xEVENT_BITS *pxEventBits = ( xEVENT_BITS * ) xEventGroup;
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const xEventBitsType uxCurrentEventBits = pxEventBits->uxEventBits;
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xEventBitsType uxReturn, uxControlBits = 0;
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/* Check the user is not attempting to wait on the bits used by the kernel
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itself, and that at least one bit is being requested. */
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configASSERT( ( uxBitsToWaitFor & taskEVENT_BITS_CONTROL_BYTES ) == 0 );
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configASSERT( uxBitsToWaitFor != 0 );
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taskENTER_CRITICAL();
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{
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if( xWaitForAllBits == pdFALSE )
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{
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/* Task only has to wait for one bit within uxBitsToWaitFor to be set. Is
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one already set? */
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if( ( uxCurrentEventBits & uxBitsToWaitFor ) != ( xEventBitsType ) 0 )
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{
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/* At least one of the bits was set. No need to block. */
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xBlockTime = 0;
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}
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}
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else
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{
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/* Task has to wait for all the bits in uxBitsToWaitFor to be set. Are they
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set already? */
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if( ( uxCurrentEventBits & uxBitsToWaitFor ) == uxBitsToWaitFor )
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{
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/* All the bits were set, no need to block. */
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xBlockTime = 0;
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}
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}
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/* The task can return now if either its wait condition is already met
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or the requested block time is 0. */
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if( xBlockTime == ( portTickType ) 0 )
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{
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/* No need to block, just set the return value. */
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uxReturn = uxCurrentEventBits;
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if( xClearOnExit != pdFALSE )
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{
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/* The user requested the bits be cleared again prior to exiting
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this function. */
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pxEventBits->uxEventBits &= ~uxBitsToWaitFor;
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}
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}
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else
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{
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/* The task is going to block to wait for its required bits to be
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set. uxControlBits are used to remember the specified behaviour of
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this call to xEventGroupWaitBits() - for use when the event bits
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unblock the task. */
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if( xClearOnExit != pdFALSE )
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{
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uxControlBits |= taskCLEAR_EVENTS_ON_EXIT_BIT;
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}
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if( xWaitForAllBits != pdFALSE )
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{
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uxControlBits |= taskWAIT_FOR_ALL_BITS;
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}
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/* Store the bits that the calling task is waiting for in the
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task's event list item so the kernel knows when a match is
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found. Then enter the blocked state. */
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vTaskPlaceOnUnorderedEventList( &( pxEventBits->xTasksWaitingForBits ), ( uxBitsToWaitFor | uxControlBits ), xBlockTime );
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portYIELD_WITHIN_API();
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}
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}
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taskEXIT_CRITICAL();
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if( xBlockTime != ( portTickType ) 0 )
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{
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/* The task blocked to wait for its required bits to be set - at this
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point either the required bits were set or the block time expired. If
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the required bits were set they will have been stored in the task's
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event list item, and they should now be retrieved then cleared. */
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uxReturn = uxTaskResetEventItemValue();
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if( ( uxReturn & taskUNBLOCKED_DUE_TO_BIT_SET_BIT ) == ( xEventBitsType ) 0 )
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{
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/* The task timed out, just return the current event bit value. */
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uxReturn = pxEventBits->uxEventBits;
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}
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else
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{
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/* The task unblocked because the bits were set. Clear the control
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bits before returning the value. */
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uxReturn &= ~taskEVENT_BITS_CONTROL_BYTES;
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}
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}
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return uxReturn;
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}
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/*-----------------------------------------------------------*/
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xEventBitsType xEventGroupClearBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToClear )
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{
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xEVENT_BITS *pxEventBits = ( xEVENT_BITS * ) xEventGroup;
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xEventBitsType uxReturn;
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/* Check the user is not attempting to clear the bits used by the kernel
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itself. */
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configASSERT( ( uxBitsToClear & taskEVENT_BITS_CONTROL_BYTES ) == 0 );
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uxBitsToClear = ~uxBitsToClear;
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taskENTER_CRITICAL();
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{
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/* The value returned is the event group value prior to the bits being
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cleared. */
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uxReturn = pxEventBits->uxEventBits;
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/* Clear the bits. */
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pxEventBits->uxEventBits &= uxBitsToClear;
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}
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taskEXIT_CRITICAL();
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return uxReturn;
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}
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/*-----------------------------------------------------------*/
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xEventBitsType xEventGroupSetBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToSet )
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{
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xListItem *pxListItem, *pxNext;
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xListItem const *pxListEnd;
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xList *pxList;
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xEventBitsType uxBitsToClear = 0, uxBitsWaitedFor, uxControlBits;
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xEVENT_BITS *pxEventBits = ( xEVENT_BITS * ) xEventGroup;
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portBASE_TYPE xMatchFound = pdFALSE;
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/* Check the user is not attempting to set the bits used by the kernel
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itself. */
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configASSERT( ( uxBitsToSet & taskEVENT_BITS_CONTROL_BYTES ) == 0 );
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pxList = &( pxEventBits->xTasksWaitingForBits );
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pxListEnd = listGET_END_MARKER( pxList ); /*lint !e826 !e740 The mini list structure is used as the list end to save RAM. This is checked and valid. */
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pxListItem = listGET_HEAD_ENTRY( pxList );
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vTaskSuspendAll();
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{
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/* Set the bits. */
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pxEventBits->uxEventBits |= uxBitsToSet;
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/* See if the new bit value should unblock any tasks. */
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while( pxListItem != pxListEnd )
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{
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pxNext = listGET_NEXT( pxListItem );
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uxBitsWaitedFor = listGET_LIST_ITEM_VALUE( pxListItem );
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/* Split the bits waited for from the control bits. */
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uxControlBits = uxBitsWaitedFor & taskEVENT_BITS_CONTROL_BYTES;
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uxBitsWaitedFor &= ~taskEVENT_BITS_CONTROL_BYTES;
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if( ( uxControlBits & taskWAIT_FOR_ALL_BITS ) == ( xEventBitsType ) 0 )
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{
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/* Just looking for single bit being set. */
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if( ( uxBitsWaitedFor & pxEventBits->uxEventBits ) != ( xEventBitsType ) 0 )
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{
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xMatchFound = pdTRUE;
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}
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}
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else if( ( uxBitsWaitedFor & pxEventBits->uxEventBits ) == uxBitsWaitedFor )
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{
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/* All bits are set. */
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xMatchFound = pdTRUE;
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}
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else
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{
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/* Need all bits to be set, but not all the bits were set. */
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}
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if( xMatchFound != pdFALSE )
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{
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/* The bits match. Should the bits be cleared on exit? */
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if( ( uxControlBits & taskCLEAR_EVENTS_ON_EXIT_BIT ) != ( xEventBitsType ) 0 )
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{
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uxBitsToClear |= uxBitsWaitedFor;
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}
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/* Store the actual event flag value in the task's event list
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item before removing the task from the event list. The
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taskUNBLOCKED_DUE_TO_BIT_SET_BIT bit is set so the task knows
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that is was unblocked due to its required bits matching, rather
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than because it timed out. */
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( void ) xTaskRemoveFromUnorderedEventList( pxListItem, pxEventBits->uxEventBits | taskUNBLOCKED_DUE_TO_BIT_SET_BIT );
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}
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/* Move onto the next list item. Note pxListItem->pxNext is not
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used here as the list item may have been removed from the event list
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and inserted into the ready/pending reading list. */
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pxListItem = pxNext;
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}
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/* Clear any bits that matched when the taskCLEAR_EVENTS_ON_EXIT_BIT
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bit was set in the control word. */
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pxEventBits->uxEventBits &= ~uxBitsToClear;
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}
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( void ) xTaskResumeAll();
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return pxEventBits->uxEventBits;
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}
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/*-----------------------------------------------------------*/
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void vEventGroupDelete( xEventGroupHandle xEventGroup )
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{
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xEVENT_BITS *pxEventBits = ( xEVENT_BITS * ) xEventGroup;
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const xList *pxTasksWaitingForBits = &( pxEventBits->xTasksWaitingForBits );
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vTaskSuspendAll();
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{
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while( listCURRENT_LIST_LENGTH( pxTasksWaitingForBits ) > ( unsigned portBASE_TYPE ) 0 )
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{
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/* Unblock the task, returning 0 as the event list is being deleted
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and cannot therefore have any bits set. */
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configASSERT( pxTasksWaitingForBits->xListEnd.pxNext != ( xListItem * ) &( pxTasksWaitingForBits->xListEnd ) );
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( void ) xTaskRemoveFromUnorderedEventList( pxTasksWaitingForBits->xListEnd.pxNext, ( portTickType ) 0 );
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}
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vPortFree( pxEventBits );
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}
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( void ) xTaskResumeAll();
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}
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/*-----------------------------------------------------------*/
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/* For internal use only - execute a 'set bits' command that was pended from
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an interrupt. */
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void vEventGroupSetBitsCallback( void *pvEventGroup, unsigned long ulBitsToSet )
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{
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( void ) xEventGroupSetBits( pvEventGroup, ( xEventBitsType ) ulBitsToSet );
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}
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@ -0,0 +1,625 @@
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/*
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||||
FreeRTOS V7.6.0 - Copyright (C) 2013 Real Time Engineers Ltd.
|
||||
All rights reserved
|
||||
|
||||
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
|
||||
|
||||
***************************************************************************
|
||||
* *
|
||||
* FreeRTOS provides completely free yet professionally developed, *
|
||||
* robust, strictly quality controlled, supported, and cross *
|
||||
* platform software that has become a de facto standard. *
|
||||
* *
|
||||
* Help yourself get started quickly and support the FreeRTOS *
|
||||
* project by purchasing a FreeRTOS tutorial book, reference *
|
||||
* manual, or both from: http://www.FreeRTOS.org/Documentation *
|
||||
* *
|
||||
* Thank you! *
|
||||
* *
|
||||
***************************************************************************
|
||||
|
||||
This file is part of the FreeRTOS distribution.
|
||||
|
||||
FreeRTOS is free software; you can redistribute it and/or modify it under
|
||||
the terms of the GNU General Public License (version 2) as published by the
|
||||
Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception.
|
||||
|
||||
>>! NOTE: The modification to the GPL is included to allow you to distribute
|
||||
>>! a combined work that includes FreeRTOS without being obliged to provide
|
||||
>>! the source code for proprietary components outside of the FreeRTOS
|
||||
>>! kernel.
|
||||
|
||||
FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
|
||||
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
||||
FOR A PARTICULAR PURPOSE. Full license text is available from the following
|
||||
link: http://www.freertos.org/a00114.html
|
||||
|
||||
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, books, training, latest versions,
|
||||
license and Real Time Engineers Ltd. contact details.
|
||||
|
||||
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
|
||||
including FreeRTOS+Trace - an indispensable productivity tool, a DOS
|
||||
compatible FAT file system, and our tiny thread aware UDP/IP stack.
|
||||
|
||||
http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
|
||||
Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS
|
||||
licenses offer ticketed support, indemnification and middleware.
|
||||
|
||||
http://www.SafeRTOS.com - High Integrity Systems also provide a safety
|
||||
engineered and independently SIL3 certified version for use in safety and
|
||||
mission critical applications that require provable dependability.
|
||||
|
||||
1 tab == 4 spaces!
|
||||
*/
|
||||
|
||||
#ifndef EVENT_GROUPS_H
|
||||
#define EVENT_GROUPS_H
|
||||
|
||||
#ifndef INC_FREERTOS_H
|
||||
#error "include FreeRTOS.h" must appear in source files before "include event_groups.h"
|
||||
#endif
|
||||
|
||||
#include "timers.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
/**
|
||||
* An event group is a collection of bits to which an application can assign a
|
||||
* meaning. For example, an application may create an event group to convey
|
||||
* the status of various CAN bus related events in which bit 0 might mean "A CAN
|
||||
* message has been received and is ready for processing", bit 1 might mean "The
|
||||
* application has queued a message that is ready for sending onto the CAN
|
||||
* network", and bit 2 might mean "it is time to send a SYNC message onto the
|
||||
* CAN network" etc. A task can then test the bit values to see which events
|
||||
* are active, and optionally enter the Blocked state to wait for a specified
|
||||
* bit or a group of specified bits to be active. To continue the CAN bus
|
||||
* example, a CAN controlling task can enter the Blocked state (and therefore
|
||||
* not consume any processing time) until either bit 0, bit 1 or bit 2 are
|
||||
* active, at which time the bit that was actually active would inform the task
|
||||
* which action it had to take (process a received message, send a message, or
|
||||
* send a SYNC).
|
||||
*
|
||||
* The event groups implementation contains intelligence to avoid race
|
||||
* conditions that would otherwise occur were an application to use a simple
|
||||
* variable for the same purpose. This is particularly important with respect
|
||||
* to when a bit within an event group is to be cleared, and when bits have to
|
||||
* be set and then tested atomically - as is the case where event groups are
|
||||
* used to create a synchronisation point between multiple tasks (a
|
||||
* 'rendezvous').
|
||||
*
|
||||
* \defgroup EventGroup
|
||||
*/
|
||||
|
||||
|
||||
|
||||
/**
|
||||
* event_groups.h
|
||||
*
|
||||
* Type by which event groups are referenced. For example, a call to
|
||||
* xEventGroupCreate() returns an xEventGroupHandle variable that can then
|
||||
* be used as a parameter to other event group functions.
|
||||
*
|
||||
* \defgroup xEventGroupHandle xEventGroupHandle
|
||||
* \ingroup EventGroup
|
||||
*/
|
||||
typedef void * xEventGroupHandle;
|
||||
|
||||
/**
|
||||
* event_groups.h
|
||||
*<pre>
|
||||
xEventGroupHandle xEventGroupCreate( void );
|
||||
</pre>
|
||||
*
|
||||
* Create a new event group. This function cannot be called from an interrupt.
|
||||
*
|
||||
* Although event groups are not related to ticks, for internal implementation
|
||||
* reasons the number of bits available for use in an event group is dependent
|
||||
* on the configUSE_16_BIT_TICKS setting in FreeRTOSConfig.h. If
|
||||
* configUSE_16_BIT_TICKS is 1 then each event group contains 8 usable bits (bit
|
||||
* 0 to bit 7). If configUSE_16_BIT_TICKS is set to 0 then each event group has
|
||||
* 24 usable bits (bit 0 to bit 23). The xEventBitsType type is used to store
|
||||
* event bits within an event group.
|
||||
*
|
||||
* @return If the event group was created then a handle to the event group is
|
||||
* returned. If there was insufficient FreeRTOS heap available to create the
|
||||
* event group then NULL is returned. See http://www.freertos.org/a00111.html
|
||||
*
|
||||
* Example usage:
|
||||
<pre>
|
||||
// Declare a variable to hold the created event group.
|
||||
xEventGroupHandle xCreatedEventGroup;
|
||||
|
||||
// Attempt to create the event group.
|
||||
xCreatedEventGroup = xEventGroupCreate();
|
||||
|
||||
// Was the event group created successfully?
|
||||
if( xCreatedEventGroup == NULL )
|
||||
{
|
||||
// The event group was not created because there was insufficient
|
||||
// FreeRTOS heap available.
|
||||
}
|
||||
else
|
||||
{
|
||||
// The event group was created.
|
||||
}
|
||||
</pre>
|
||||
* \defgroup xEventGroupCreate xEventGroupCreate
|
||||
* \ingroup EventGroup
|
||||
*/
|
||||
xEventGroupHandle xEventGroupCreate( void ) PRIVILEGED_FUNCTION;
|
||||
|
||||
/**
|
||||
* event_groups.h
|
||||
*<pre>
|
||||
xEventBitsType xEventGroupWaitBits( xEventGroupHandle xEventGroup,
|
||||
xEventBitsType uxBitsToWaitFor,
|
||||
portBASE_TYPE xClearOnExit,
|
||||
portBASE_TYPE xWaitForAllBits,
|
||||
portTickType xBlockTime );
|
||||
</pre>
|
||||
*
|
||||
* [Potentially] block to wait for one or more bits to be set within a
|
||||
* previously created event group.
|
||||
*
|
||||
* This function cannot be called from an interrupt.
|
||||
*
|
||||
* @param xEventGroup The event group in which the bits are being tested. The
|
||||
* event group must have previously been created using a call to
|
||||
* xEventGroupCreate().
|
||||
*
|
||||
* @param uxBitsToWaitFor A bitwise value that indicates the bit or bits to test
|
||||
* inside the event group. For example, to wait for bit 0 and/or bit 2 set
|
||||
* uxBitsToWaitFor to 0x05. To wait for bits 0 and/or bit 1 and/or bit 2 set
|
||||
* uxBitsToWaitFor to 0x07. Etc.
|
||||
*
|
||||
* @param xClearOnExit If xClearOnExit is set to pdTRUE then any bits within
|
||||
* uxBitsToWaitFor that are set within the event group will be cleared before
|
||||
* xEventGroupWaitBits() returns. If xClearOnExit is set to pdFALSE then the
|
||||
* bits set in the event group are not altered when the call to
|
||||
* xEventGroupWaitBits() returns.
|
||||
*
|
||||
* @param xWaitForAllBits If xWaitForAllBits is set to pdTRUE then
|
||||
* xEventGroupWaitBits() will return when either all the bits in uxBitsToWaitFor
|
||||
* are set or the specified block time expires. If xWaitForAllBits is set to
|
||||
* pdFALSE then xEventGroupWaitBits() will return when any one of the bits set
|
||||
* in uxBitsToWaitFor is set or the specified block time expires.
|
||||
*
|
||||
* @param xBlockTime The maximum amount of time (specified in 'ticks') to wait
|
||||
* for one/all (depending on the xWaitForAllBits value) of the bits specified by
|
||||
* uxBitsToWaitFor to become set.
|
||||
*
|
||||
* @return The value of the event group at the time either the bits being waited
|
||||
* for became set, or the block time expired. Test the return value to know
|
||||
* which bits were set. If xEventGroupWaitBits() returned because its timeout
|
||||
* expired then not all the bits being waited for will be set. If
|
||||
* xEventGroupWaitBits() returned because the bits it was waiting for were set
|
||||
* then the returned value is the event group value before any bits were
|
||||
* automatically cleared because the xClearOnExit parameter was set to pdTRUE.
|
||||
*
|
||||
* Example usage:
|
||||
<pre>
|
||||
#define BIT_0 ( 1 << 0 )
|
||||
#define BIT_4 ( 1 << 4 )
|
||||
|
||||
void aFunction( xEventGroupHandle xEventGroup )
|
||||
{
|
||||
xEventBitsType uxBits;
|
||||
const portTickType xBlockTime = 100 / portTICK_RATE_MS;
|
||||
|
||||
// Wait a maximum of 100ms for either bit 0 or bit 4 to be set within
|
||||
// the event group. Clear the bits before exiting.
|
||||
uxBits = xEventGroupWaitBits(
|
||||
xEventGroup, // The event group being tested.
|
||||
BIT_0 | BIT_4, // The bits within the event group to wait for.
|
||||
pdTRUE, // BIT_0 and BIT_4 should be cleared before returning.
|
||||
pdFALSE, // Don't wait for both bits, either bit will do.
|
||||
xBlockTime ); // Wait a maximum of 100ms for either bit to be set.
|
||||
|
||||
if( ( uxBits & ( BIT_0 | BIT_4 ) ) == ( BIT_0 | BIT_4 ) )
|
||||
{
|
||||
// xEventGroupWaitBits() returned because both bits were set.
|
||||
}
|
||||
else if( ( uxBits & BIT_0 ) != 0 )
|
||||
{
|
||||
// xEventGroupWaitBits() returned because just BIT_0 was set.
|
||||
}
|
||||
else if( ( uxBits & BIT_4 ) != 0 )
|
||||
{
|
||||
// xEventGroupWaitBits() returned because just BIT_4 was set.
|
||||
}
|
||||
else
|
||||
{
|
||||
// xEventGroupWaitBits() returned because xBlockTime ticks passed
|
||||
// without either BIT_0 or BIT_4 becoming set.
|
||||
}
|
||||
}
|
||||
</pre>
|
||||
* \defgroup xEventGroupWaitBits xEventGroupWaitBits
|
||||
* \ingroup EventGroup
|
||||
*/
|
||||
xEventBitsType xEventGroupWaitBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToWaitFor, portBASE_TYPE xClearOnExit, portBASE_TYPE xWaitForAllBits, portTickType xBlockTime ) PRIVILEGED_FUNCTION;
|
||||
|
||||
/**
|
||||
* event_groups.h
|
||||
*<pre>
|
||||
xEventBitsType xEventGroupClearBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToClear );
|
||||
</pre>
|
||||
*
|
||||
* Clear bits within an event group. This function cannot be called from an
|
||||
* interrupt.
|
||||
*
|
||||
* @param xEventGroup The event group in which the bits are to be cleared.
|
||||
*
|
||||
* @param uxBitsToClear A bitwise value that indicates the bit or bits to clear
|
||||
* in the event group. For example, to clear bit 3 only, set uxBitsToClear to
|
||||
* 0x08. To clear bit 3 and bit 0 set uxBitsToClear to 0x09.
|
||||
*
|
||||
* @return The value of the event group before the specified bits were cleared.
|
||||
*
|
||||
* Example usage:
|
||||
<pre>
|
||||
#define BIT_0 ( 1 << 0 )
|
||||
#define BIT_4 ( 1 << 4 )
|
||||
|
||||
void aFunction( xEventGroupHandle xEventGroup )
|
||||
{
|
||||
xEventBitsType uxBits;
|
||||
|
||||
// Clear bit 0 and bit 4 in xEventGroup.
|
||||
uxBits = xEventGroupClearBits(
|
||||
xEventGroup, // The event group being updated.
|
||||
BIT_0 | BIT_4 );// The bits being cleared.
|
||||
|
||||
if( ( uxBits & ( BIT_0 | BIT_4 ) ) == ( BIT_0 | BIT_4 ) )
|
||||
{
|
||||
// Both bit 0 and bit 4 were set before the call to
|
||||
// xEventGroupClearBits() was called. Both will now be clear (not
|
||||
// set).
|
||||
}
|
||||
else if( ( uxBits & BIT_0 ) != 0 )
|
||||
{
|
||||
// Bit 0 was set before xEventGroupClearBits() was called. It will
|
||||
// now be clear.
|
||||
}
|
||||
else if( ( uxBits & BIT_4 ) != 0 )
|
||||
{
|
||||
// Bit 4 was set before xEventGroupClearBits() was called. It will
|
||||
// now be clear.
|
||||
}
|
||||
else
|
||||
{
|
||||
// Neither bit 0 nor bit 4 were set in the first place.
|
||||
}
|
||||
}
|
||||
</pre>
|
||||
* \defgroup xEventGroupClearBits xEventGroupClearBits
|
||||
* \ingroup EventGroup
|
||||
*/
|
||||
xEventBitsType xEventGroupClearBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToClear ) PRIVILEGED_FUNCTION;
|
||||
|
||||
/**
|
||||
* event_groups.h
|
||||
*<pre>
|
||||
xEventBitsType xEventGroupSetBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToSet );
|
||||
</pre>
|
||||
*
|
||||
* Set bits within an event group.
|
||||
* This function cannot be called from an interrupt. xEventGroupSetBitsFromISR()
|
||||
* is a version that can be called from an interrupt.
|
||||
*
|
||||
* Setting bits in an event group will automatically unblock tasks that are
|
||||
* blocked waiting for the bits.
|
||||
*
|
||||
* @param xEventGroup The event group in which the bits are to be set.
|
||||
*
|
||||
* @param uxBitsToSet A bitwise value that indicates the bit or bits to set.
|
||||
* For example, to set bit 3 only, set uxBitsToSet to 0x08. To set bit 3
|
||||
* and bit 0 set uxBitsToSet to 0x09.
|
||||
*
|
||||
* @return The value of the event group at the time the call to
|
||||
* xEventGroupSetBits() returns. There are two reasons why the returned value
|
||||
* might have the bits specified by the uxBitsToSet parameter cleared. First,
|
||||
* if setting a bit results in a task that was waiting for the bit leaving the
|
||||
* blocked state then it is possible the bit will be cleared automatically
|
||||
* (see the xClearBitOnExit parameter of xEventGroupWaitBits()). Second, any
|
||||
* unblocked (or otherwise Ready state) task that has a priority above that of
|
||||
* the task that called xEventGroupSetBits() will execute and may change the
|
||||
* event group value before the call to xEventGroupSetBits() returns.
|
||||
*
|
||||
* Example usage:
|
||||
<pre>
|
||||
#define BIT_0 ( 1 << 0 )
|
||||
#define BIT_4 ( 1 << 4 )
|
||||
|
||||
void aFunction( xEventGroupHandle xEventGroup )
|
||||
{
|
||||
xEventBitsType uxBits;
|
||||
|
||||
// Set bit 0 and bit 4 in xEventGroup.
|
||||
uxBits = xEventGroupSetBits(
|
||||
xEventGroup, // The event group being updated.
|
||||
BIT_0 | BIT_4 );// The bits being set.
|
||||
|
||||
if( ( uxBits & ( BIT_0 | BIT_4 ) ) == ( BIT_0 | BIT_4 ) )
|
||||
{
|
||||
// Both bit 0 and bit 4 remained set when the function returned.
|
||||
}
|
||||
else if( ( uxBits & BIT_0 ) != 0 )
|
||||
{
|
||||
// Bit 0 remained set when the function returned, but bit 4 was
|
||||
// cleared. It might be that bit 4 was cleared automatically as a
|
||||
// task that was waiting for bit 4 was removed from the Blocked
|
||||
// state.
|
||||
}
|
||||
else if( ( uxBits & BIT_4 ) != 0 )
|
||||
{
|
||||
// Bit 4 remained set when the function returned, but bit 0 was
|
||||
// cleared. It might be that bit 0 was cleared automatically as a
|
||||
// task that was waiting for bit 0 was removed from the Blocked
|
||||
// state.
|
||||
}
|
||||
else
|
||||
{
|
||||
// Neither bit 0 nor bit 4 remained set. It might be that a task
|
||||
// was waiting for either or both of the bits to be set, and the
|
||||
// bits were cleared as the task left the Blocked state.
|
||||
}
|
||||
}
|
||||
</pre>
|
||||
* \defgroup xEventGroupSetBits xEventGroupSetBits
|
||||
* \ingroup EventGroup
|
||||
*/
|
||||
xEventBitsType xEventGroupSetBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToSet ) PRIVILEGED_FUNCTION;
|
||||
|
||||
/**
|
||||
* event_groups.h
|
||||
*<pre>
|
||||
xEventBitsType xEventGroupSetBitsFromISR( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToSet, portBASE_TYPE *pxHigherPriorityTaskWoken );
|
||||
</pre>
|
||||
*
|
||||
* A version of xEventGroupSetBits() that can be called from an interrupt.
|
||||
*
|
||||
* Setting bits in an event group is not a deterministic operation because there
|
||||
* are an unknown number of tasks that may be waiting for the bit or bits being
|
||||
* set. FreeRTOS does not allow nondeterministic operations to be performed in
|
||||
* interrupts or from critical sections. Therefore xEventGroupSetBitFromISR()
|
||||
* sends a message to the timer task to have the set operation performed in the
|
||||
* context of the timer task - where a scheduler lock is used in place of a
|
||||
* critical section.
|
||||
*
|
||||
* @param xEventGroup The event group in which the bits are to be set.
|
||||
*
|
||||
* @param uxBitsToSet A bitwise value that indicates the bit or bits to set.
|
||||
* For example, to set bit 3 only, set uxBitsToSet to 0x08. To set bit 3
|
||||
* and bit 0 set uxBitsToSet to 0x09.
|
||||
*
|
||||
* @ pxHigherPriorityTaskWoken As mentioned above, calling this function will
|
||||
* result in a message being sent to the timer daemon task. If the priority of
|
||||
* the timer daemon task is higher than the priority of the currently running
|
||||
* task (the task the interrupt interrupted) then *pxHigherPriorityTaskWoken
|
||||
* will be set to pdTRUE by xEventGroupSetBitsFromISR(), indicating that a
|
||||
* context switch should be requested before the interrupt exits. For that
|
||||
* reason *pxHigherPriorityTaskWoken must be initialised to pdFALSE. See the
|
||||
* example code below.
|
||||
*
|
||||
* @return If the callback request was registered successfully then pdPASS is
|
||||
* returned, otherwise pdFALSE is returned. pdFALSE will be returned if the
|
||||
* timer service queue was full.
|
||||
*
|
||||
* Example usage:
|
||||
<pre>
|
||||
#define BIT_0 ( 1 << 0 )
|
||||
#define BIT_4 ( 1 << 4 )
|
||||
|
||||
// An event group which it is assume has already been created by a call to
|
||||
// xEventGroupCreate().
|
||||
xEventGroupHandle xEventGroup;
|
||||
|
||||
void anInterruptHandler( void )
|
||||
{
|
||||
portBASE_TYPE xHigherPriorityTaskWoken;
|
||||
|
||||
// xHigherPriorityTaskWoken must be initialised to pdFALSE;
|
||||
xHigherPriorityTaskWoken = pdFALSE;
|
||||
|
||||
// Set bit 0 and bit 4 in xEventGroup.
|
||||
uxBits = xEventGroupSetBitsFromISR(
|
||||
xEventGroup, // The event group being updated.
|
||||
BIT_0 | BIT_4 // The bits being set.
|
||||
&xHigherPriorityTaskWoken );
|
||||
|
||||
// If xHigherPriorityTaskWoken is now set to pdTRUE then a context
|
||||
// switch should be requested. The macro used is port specific and will
|
||||
// be either portYIELD_FROM_ISR() or portEND_SWITCHING_ISR() - refer to
|
||||
// the documentation page for the port being used.
|
||||
portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
|
||||
}
|
||||
</pre>
|
||||
* \defgroup xEventGroupSetBitsFromISR xEventGroupSetBitsFromISR
|
||||
* \ingroup EventGroup
|
||||
*/
|
||||
#define xEventGroupSetBitsFromISR( xEventGroup, uxBitsToSet, pxHigherPriorityTaskWoken ) xTimerPendCallbackFromISR( vEventGroupSetBitsCallback, ( void * ) xEventGroup, ( unsigned long ) uxBitsToSet, pxHigherPriorityTaskWoken )
|
||||
|
||||
/**
|
||||
* event_groups.h
|
||||
*<pre>
|
||||
xEventBitsType xEventGroupSync( xEventGroupHandle xEventGroup,
|
||||
xEventBitsType uxBitsToSet,
|
||||
xEventBitsType uxBitsToWaitFor,
|
||||
portTickType xBlockTime );
|
||||
</pre>
|
||||
*
|
||||
* Atomically set bits within an event group, then wait for a combination of
|
||||
* bits to be set within the same event group. This functionality is typically
|
||||
* used to synchronise multiple tasks, where each task has to wait for the other
|
||||
* tasks to reach a synchronisation point before proceeding.
|
||||
*
|
||||
* This function cannot be used from an interrupt.
|
||||
*
|
||||
* The function will return before its block time expires if the bits specified
|
||||
* by the uxBitsToWait parameter are set, or become set within that time. In
|
||||
* this case all the bits specified by uxBitsToWait will be automatically
|
||||
* cleared before the function returns.
|
||||
*
|
||||
* @param xEventGroup The event group in which the bits are being tested. The
|
||||
* event group must have previously been created using a call to
|
||||
* xEventGroupCreate().
|
||||
*
|
||||
* @param uxBitsToSet The bits to set in the event group before determining
|
||||
* if, and possibly waiting for, all the bits specified by the uxBitsToWait
|
||||
* parameter are set.
|
||||
*
|
||||
* @param uxBitsToWaitFor A bitwise value that indicates the bit or bits to test
|
||||
* inside the event group. For example, to wait for bit 0 and bit 2 set
|
||||
* uxBitsToWaitFor to 0x05. To wait for bits 0 and bit 1 and bit 2 set
|
||||
* uxBitsToWaitFor to 0x07. Etc.
|
||||
*
|
||||
* @param xBlockTime The maximum amount of time (specified in 'ticks') to wait
|
||||
* for all of the bits specified by uxBitsToWaitFor to become set.
|
||||
*
|
||||
* @return The value of the event group at the time either the bits being waited
|
||||
* for became set, or the block time expired. Test the return value to know
|
||||
* which bits were set. If xEventGroupSync() returned because its timeout
|
||||
* expired then not all the bits being waited for will be set. If
|
||||
* xEventGroupSync() returned because all the bits it was waiting for were
|
||||
* set then the returned value is the event group value before any bits were
|
||||
* automatically cleared.
|
||||
*
|
||||
* Example usage:
|
||||
<pre>
|
||||
// Bits used by the three tasks.
|
||||
#define TASK_0_BIT ( 1 << 0 )
|
||||
#define TASK_1_BIT ( 1 << 1 )
|
||||
#define TASK_2_BIT ( 1 << 2 )
|
||||
|
||||
#define ALL_SYNC_BITS ( TASK_0_BIT | TASK_1_BIT | TASK_2_BIT )
|
||||
|
||||
// Use an event group to synchronise three tasks. It is assumed this event
|
||||
// group has already been created elsewhere.
|
||||
xEventGroupHandle xEventBits;
|
||||
|
||||
void vTask0( void *pvParameters )
|
||||
{
|
||||
xEventBitsType uxReturn;
|
||||
portTickType xBlockTime = 100 / portTICK_RATE_MS;
|
||||
|
||||
for( ;; )
|
||||
{
|
||||
// Perform task functionality here.
|
||||
|
||||
// Set bit 0 in the event flag to note this task has reached the
|
||||
// sync point. The other two tasks will set the other two bits defined
|
||||
// by ALL_SYNC_BITS. All three tasks have reached the synchronisation
|
||||
// point when all the ALL_SYNC_BITS are set. Wait a maximum of 100ms
|
||||
// for this to happen.
|
||||
uxReturn = xEventGroupSync( xEventBits, TASK_0_BIT, ALL_SYNC_BITS, xBlockTime );
|
||||
|
||||
if( ( uxReturn & ALL_SYNC_BITS ) == ALL_SYNC_BITS )
|
||||
{
|
||||
// All three tasks reached the synchronisation point before the call
|
||||
// to xEventGroupSync() timed out.
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
void vTask1( void *pvParameters )
|
||||
{
|
||||
for( ;; )
|
||||
{
|
||||
// Perform task functionality here.
|
||||
|
||||
// Set bit 1 in the event flag to note this task has reached the
|
||||
// synchronisation point. The other two tasks will set the other two
|
||||
// bits defined by ALL_SYNC_BITS. All three tasks have reached the
|
||||
// synchronisation point when all the ALL_SYNC_BITS are set. Wait
|
||||
// indefinitely for this to happen.
|
||||
xEventGroupSync( xEventBits, TASK_1_BIT, ALL_SYNC_BITS, portMAX_DELAY );
|
||||
|
||||
// xEventGroupSync() was called with an indefinite block time, so
|
||||
// this task will only reach here if the syncrhonisation was made by all
|
||||
// three tasks, so there is no need to test the return value.
|
||||
}
|
||||
}
|
||||
|
||||
void vTask2( void *pvParameters )
|
||||
{
|
||||
for( ;; )
|
||||
{
|
||||
// Perform task functionality here.
|
||||
|
||||
// Set bit 2 in the event flag to note this task has reached the
|
||||
// synchronisation point. The other two tasks will set the other two
|
||||
// bits defined by ALL_SYNC_BITS. All three tasks have reached the
|
||||
// synchronisation point when all the ALL_SYNC_BITS are set. Wait
|
||||
// indefinitely for this to happen.
|
||||
xEventGroupSync( xEventBits, TASK_2_BIT, ALL_SYNC_BITS, portMAX_DELAY );
|
||||
|
||||
// xEventGroupSync() was called with an indefinite block time, so
|
||||
// this task will only reach here if the syncrhonisation was made by all
|
||||
// three tasks, so there is no need to test the return value.
|
||||
}
|
||||
}
|
||||
|
||||
</pre>
|
||||
* \defgroup xEventGroupSync xEventGroupSync
|
||||
* \ingroup EventGroup
|
||||
*/
|
||||
xEventBitsType xEventGroupSync( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToSet, xEventBitsType uxBitsToWaitFor, portTickType xBlockTime ) PRIVILEGED_FUNCTION;
|
||||
|
||||
|
||||
/**
|
||||
* event_groups.h
|
||||
*<pre>
|
||||
xEventBitsType xEventGroupGetBits( xEventGroupHandle xEventGroup );
|
||||
</pre>
|
||||
*
|
||||
* Returns the current value of the bits in an event group. This function
|
||||
* cannot be used from an interrupt.
|
||||
*
|
||||
* @param xEventGroup The event group being queried.
|
||||
*
|
||||
* @return The event group bits at the time xEventGroupGetBits() was called.
|
||||
*
|
||||
* \defgroup xEventGroupGetBits xEventGroupGetBits
|
||||
* \ingroup EventGroup
|
||||
*/
|
||||
#define xEventGroupGetBits( xEventGroup ) xEventGroupClearBits( xEventGroup, 0 )
|
||||
|
||||
/**
|
||||
* event_groups.h
|
||||
*<pre>
|
||||
void xEventGroupDelete( xEventGroupHandle xEventGroup );
|
||||
</pre>
|
||||
*
|
||||
* Delete an event group that was previously created by a call to
|
||||
* xEventGroupCreate(). Tasks that are blocked on the event group will be
|
||||
* unblocked and obtain 0 as the event group's value.
|
||||
*
|
||||
* @param xEventGroup The event group being deleted.
|
||||
*/
|
||||
void vEventGroupDelete( xEventGroupHandle xEventGroup );
|
||||
|
||||
/* For internal use only. */
|
||||
void vEventGroupSetBitsCallback( void *pvEventGroup, unsigned long ulBitsToSet );
|
||||
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif /* EVENT_GROUPS_H */
|
||||
|
||||
|
Loading…
Reference in New Issue