www.freertos.org

Dependents:   mbed_freeRTOS_send

Fork of FreeRTOS by Rohit Grover

Revision:
0:8e57f3e9cc89
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Source/list.c	Fri Jan 24 14:56:04 2014 +0000
@@ -0,0 +1,204 @@
+/*
+    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!
+*/
+
+
+#include <stdlib.h>
+#include "FreeRTOS.h"
+#include "list.h"
+
+/*-----------------------------------------------------------
+ * PUBLIC LIST API documented in list.h
+ *----------------------------------------------------------*/
+
+void vListInitialise( xList * 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 = ( xListItem * ) &( 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 = ( xListItem * ) &( 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 = ( xListItem * ) &( 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 = ( unsigned portBASE_TYPE ) 0U;
+}
+/*-----------------------------------------------------------*/
+
+void vListInitialiseItem( xListItem * const pxItem )
+{
+	/* Make sure the list item is not recorded as being on a list. */
+	pxItem->pvContainer = NULL;
+}
+/*-----------------------------------------------------------*/
+
+void vListInsertEnd( xList * const pxList, xListItem * const pxNewListItem )
+{
+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. */
+	pxIndex = pxList->pxIndex;
+
+	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( xList * const pxList, xListItem * const pxNewListItem )
+{
+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, 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.
+		**********************************************************************/
+
+		for( pxIterator = ( xListItem * ) &( 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 )++;
+}
+/*-----------------------------------------------------------*/
+
+unsigned portBASE_TYPE uxListRemove( xListItem * const 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 )--;
+
+	return pxList->uxNumberOfItems;
+}
+/*-----------------------------------------------------------*/
+