/* | |
FreeRTOS V7.2.0 - Copyright (C) 2012 Real Time Engineers Ltd. | |
*************************************************************************** | |
* * | |
* FreeRTOS tutorial books are available in pdf and paperback. * | |
* Complete, revised, and edited pdf reference manuals are also * | |
* available. * | |
* * | |
* Purchasing FreeRTOS documentation will not only help you, by * | |
* ensuring you get running as quickly as possible and with an * | |
* in-depth knowledge of how to use FreeRTOS, it will also help * | |
* the FreeRTOS project to continue with its mission of providing * | |
* professional grade, cross platform, de facto standard solutions * | |
* for microcontrollers - completely free of charge! * | |
* * | |
* >>> See http://www.FreeRTOS.org/Documentation for details. <<< * | |
* * | |
* Thank you for using FreeRTOS, and thank you for your support! * | |
* * | |
*************************************************************************** | |
This file is part of the FreeRTOS distribution. | |
FreeRTOS is free software; you can redistribute it and/or modify it under | |
the terms of the GNU General Public License (version 2) as published by the | |
Free Software Foundation AND MODIFIED BY the FreeRTOS exception. | |
>>>NOTE<<< The modification to the GPL is included to allow you to | |
distribute a combined work that includes FreeRTOS without being obliged to | |
provide the source code for proprietary components outside of the FreeRTOS | |
kernel. FreeRTOS is distributed in the hope that it will be useful, but | |
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY | |
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
more details. You should have received a copy of the GNU General Public | |
License and the FreeRTOS license exception along with FreeRTOS; if not it | |
can be viewed here: http://www.freertos.org/a00114.html and also obtained | |
by writing to Richard Barry, contact details for whom are available on the | |
FreeRTOS WEB site. | |
1 tab == 4 spaces! | |
*************************************************************************** | |
* * | |
* Having a problem? Start by reading the FAQ "My application does * | |
* not run, what could be wrong? * | |
* * | |
* http://www.FreeRTOS.org/FAQHelp.html * | |
* * | |
*************************************************************************** | |
http://www.FreeRTOS.org - Documentation, training, latest information, | |
license and contact details. | |
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products, | |
including FreeRTOS+Trace - an indispensable productivity tool. | |
Real Time Engineers ltd license FreeRTOS to High Integrity Systems, who sell | |
the code with commercial support, indemnification, and middleware, under | |
the OpenRTOS brand: http://www.OpenRTOS.com. High Integrity Systems also | |
provide a safety engineered and independently SIL3 certified version under | |
the SafeRTOS brand: http://www.SafeRTOS.com. | |
*/ | |
#include <stdlib.h> | |
#include "FreeRTOS.h" | |
#include "list.h" | |
/*----------------------------------------------------------- | |
* PUBLIC LIST API documented in list.h | |
*----------------------------------------------------------*/ | |
void vListInitialise( xList *pxList ) | |
{ | |
/* The list structure contains a list item which is used to mark the | |
end of the list. To initialise the list the list end is inserted | |
as the only list entry. */ | |
pxList->pxIndex = ( xListItem * ) &( pxList->xListEnd ); | |
/* The list end value is the highest possible value in the list to | |
ensure it remains at the end of the list. */ | |
pxList->xListEnd.xItemValue = portMAX_DELAY; | |
/* The list end next and previous pointers point to itself so we know | |
when the list is empty. */ | |
pxList->xListEnd.pxNext = ( xListItem * ) &( pxList->xListEnd ); | |
pxList->xListEnd.pxPrevious = ( xListItem * ) &( pxList->xListEnd ); | |
pxList->uxNumberOfItems = ( unsigned portBASE_TYPE ) 0U; | |
} | |
/*-----------------------------------------------------------*/ | |
void vListInitialiseItem( xListItem *pxItem ) | |
{ | |
/* Make sure the list item is not recorded as being on a list. */ | |
pxItem->pvContainer = NULL; | |
} | |
/*-----------------------------------------------------------*/ | |
void vListInsertEnd( xList *pxList, xListItem *pxNewListItem ) | |
{ | |
volatile xListItem * pxIndex; | |
/* Insert a new list item into pxList, but rather than sort the list, | |
makes the new list item the last item to be removed by a call to | |
pvListGetOwnerOfNextEntry. This means it has to be the item pointed to by | |
the pxIndex member. */ | |
pxIndex = pxList->pxIndex; | |
pxNewListItem->pxNext = pxIndex->pxNext; | |
pxNewListItem->pxPrevious = pxList->pxIndex; | |
pxIndex->pxNext->pxPrevious = ( volatile xListItem * ) pxNewListItem; | |
pxIndex->pxNext = ( volatile xListItem * ) pxNewListItem; | |
pxList->pxIndex = ( volatile xListItem * ) pxNewListItem; | |
/* Remember which list the item is in. */ | |
pxNewListItem->pvContainer = ( void * ) pxList; | |
( pxList->uxNumberOfItems )++; | |
} | |
/*-----------------------------------------------------------*/ | |
void vListInsert( xList *pxList, xListItem *pxNewListItem ) | |
{ | |
volatile xListItem *pxIterator; | |
portTickType xValueOfInsertion; | |
/* Insert the new list item into the list, sorted in ulListItem order. */ | |
xValueOfInsertion = pxNewListItem->xItemValue; | |
/* If the list already contains a list item with the same item value then | |
the new list item should be placed after it. This ensures that TCB's which | |
are stored in ready lists (all of which have the same ulListItem value) | |
get an equal share of the CPU. However, if the xItemValue is the same as | |
the back marker the iteration loop below will not end. This means we need | |
to guard against this by checking the value first and modifying the | |
algorithm slightly if necessary. */ | |
if( xValueOfInsertion == portMAX_DELAY ) | |
{ | |
pxIterator = pxList->xListEnd.pxPrevious; | |
} | |
else | |
{ | |
/* *** NOTE *********************************************************** | |
If you find your application is crashing here then likely causes are: | |
1) Stack overflow - | |
see http://www.freertos.org/Stacks-and-stack-overflow-checking.html | |
2) Incorrect interrupt priority assignment, especially on Cortex-M3 | |
parts where numerically high priority values denote low actual | |
interrupt priories, which can seem counter intuitive. See | |
configMAX_SYSCALL_INTERRUPT_PRIORITY on http://www.freertos.org/a00110.html | |
3) Calling an API function from within a critical section or when | |
the scheduler is suspended. | |
4) Using a queue or semaphore before it has been initialised or | |
before the scheduler has been started (are interrupts firing | |
before vTaskStartScheduler() has been called?). | |
See http://www.freertos.org/FAQHelp.html for more tips. | |
**********************************************************************/ | |
for( pxIterator = ( xListItem * ) &( pxList->xListEnd ); pxIterator->pxNext->xItemValue <= xValueOfInsertion; pxIterator = pxIterator->pxNext ) | |
{ | |
/* There is nothing to do here, we are just iterating to the | |
wanted insertion position. */ | |
} | |
} | |
pxNewListItem->pxNext = pxIterator->pxNext; | |
pxNewListItem->pxNext->pxPrevious = ( volatile xListItem * ) pxNewListItem; | |
pxNewListItem->pxPrevious = pxIterator; | |
pxIterator->pxNext = ( volatile xListItem * ) pxNewListItem; | |
/* Remember which list the item is in. This allows fast removal of the | |
item later. */ | |
pxNewListItem->pvContainer = ( void * ) pxList; | |
( pxList->uxNumberOfItems )++; | |
} | |
/*-----------------------------------------------------------*/ | |
void vListRemove( xListItem *pxItemToRemove ) | |
{ | |
xList * pxList; | |
pxItemToRemove->pxNext->pxPrevious = pxItemToRemove->pxPrevious; | |
pxItemToRemove->pxPrevious->pxNext = pxItemToRemove->pxNext; | |
/* The list item knows which list it is in. Obtain the list from the list | |
item. */ | |
pxList = ( xList * ) pxItemToRemove->pvContainer; | |
/* Make sure the index is left pointing to a valid item. */ | |
if( pxList->pxIndex == pxItemToRemove ) | |
{ | |
pxList->pxIndex = pxItemToRemove->pxPrevious; | |
} | |
pxItemToRemove->pvContainer = NULL; | |
( pxList->uxNumberOfItems )--; | |
} | |
/*-----------------------------------------------------------*/ | |