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Diffstat (limited to 'rtos/FreeRTOS/Source/list.c')
| -rw-r--r-- | rtos/FreeRTOS/Source/list.c | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/rtos/FreeRTOS/Source/list.c b/rtos/FreeRTOS/Source/list.c new file mode 100644 index 0000000..307f956 --- /dev/null +++ b/rtos/FreeRTOS/Source/list.c @@ -0,0 +1,204 @@ +/* + FreeRTOS V8.0.0 - Copyright (C) 2014 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! +*/ + + +#include <stdlib.h> +#include "FreeRTOS.h" +#include "list.h" + +/*----------------------------------------------------------- + * PUBLIC LIST API documented in list.h + *----------------------------------------------------------*/ + +void vListInitialise( List_t * const 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 = ( ListItem_t * ) &( pxList->xListEnd ); /*lint !e826 !e740 The mini list structure is used as the list end to save RAM. This is checked and valid. */ + + /* 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 = ( ListItem_t * ) &( pxList->xListEnd ); /*lint !e826 !e740 The mini list structure is used as the list end to save RAM. This is checked and valid. */ + pxList->xListEnd.pxPrevious = ( ListItem_t * ) &( pxList->xListEnd );/*lint !e826 !e740 The mini list structure is used as the list end to save RAM. This is checked and valid. */ + + pxList->uxNumberOfItems = ( UBaseType_t ) 0U; +} +/*-----------------------------------------------------------*/ + +void vListInitialiseItem( ListItem_t * const pxItem ) +{ + /* Make sure the list item is not recorded as being on a list. */ + pxItem->pvContainer = NULL; +} +/*-----------------------------------------------------------*/ + +void vListInsertEnd( List_t * const pxList, ListItem_t * const pxNewListItem ) +{ +ListItem_t * const pxIndex = pxList->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 + listGET_OWNER_OF_NEXT_ENTRY(). */ + pxNewListItem->pxNext = pxIndex; + pxNewListItem->pxPrevious = pxIndex->pxPrevious; + pxIndex->pxPrevious->pxNext = pxNewListItem; + pxIndex->pxPrevious = pxNewListItem; + + /* Remember which list the item is in. */ + pxNewListItem->pvContainer = ( void * ) pxList; + + ( pxList->uxNumberOfItems )++; +} +/*-----------------------------------------------------------*/ + +void vListInsert( List_t * const pxList, ListItem_t * const pxNewListItem ) +{ +ListItem_t *pxIterator; +const TickType_t xValueOfInsertion = pxNewListItem->xItemValue; + + /* Insert the new list item into the list, sorted in xItemValue order. + + 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 xItemValue 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, or calling an API function that does + not end in "FromISR" from an interrupt. + 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, and ensure + configASSERT() is defined! http://www.freertos.org/a00110.html#configASSERT + **********************************************************************/ + + for( pxIterator = ( ListItem_t * ) &( pxList->xListEnd ); pxIterator->pxNext->xItemValue <= xValueOfInsertion; pxIterator = pxIterator->pxNext ) /*lint !e826 !e740 The mini list structure is used as the list end to save RAM. This is checked and valid. */ + { + /* There is nothing to do here, we are just iterating to the + wanted insertion position. */ + } + } + + pxNewListItem->pxNext = pxIterator->pxNext; + pxNewListItem->pxNext->pxPrevious = pxNewListItem; + pxNewListItem->pxPrevious = pxIterator; + pxIterator->pxNext = pxNewListItem; + + /* Remember which list the item is in. This allows fast removal of the + item later. */ + pxNewListItem->pvContainer = ( void * ) pxList; + + ( pxList->uxNumberOfItems )++; +} +/*-----------------------------------------------------------*/ + +UBaseType_t uxListRemove( ListItem_t * const pxItemToRemove ) +{ +/* The list item knows which list it is in. Obtain the list from the list +item. */ +List_t * const pxList = ( List_t * ) pxItemToRemove->pvContainer; + + pxItemToRemove->pxNext->pxPrevious = pxItemToRemove->pxPrevious; + pxItemToRemove->pxPrevious->pxNext = pxItemToRemove->pxNext; + + /* Make sure the index is left pointing to a valid item. */ + if( pxList->pxIndex == pxItemToRemove ) + { + pxList->pxIndex = pxItemToRemove->pxPrevious; + } + else + { + mtCOVERAGE_TEST_MARKER(); + } + + pxItemToRemove->pvContainer = NULL; + ( pxList->uxNumberOfItems )--; + + return pxList->uxNumberOfItems; +} +/*-----------------------------------------------------------*/ + |