//列表項(xiàng)數(shù)據(jù)結(jié)構(gòu)
typedef struct xLIST_ITEM
{
	TickType_t xItemValue;  //輔助值，用作節(jié)點(diǎn)做順序排序
	struct xLIST_ITEM * pxNext;//后繼指針
	struct xLIST_ITEM * pxPrevious;//前驅(qū)指針
	void * pvOwner;      //指向擁有該列表項(xiàng)的內(nèi)核對(duì)象，通常是TCB
	void * pvContainer;  //指向該列表項(xiàng)所在的列表
}ListItem_t;

void vListInitialiseItem(ListItem_t * const pxItem)
{
//初始化該列表項(xiàng)所在列表指針指向NULL，表示還沒插入任何列表
		pxItem->pvContainer = NULL;
}

typedef struct xLIST
{
	UBaseType_t uxNumberOfItems; //指示這條列表上有多少個(gè)列表項(xiàng)
	ListItem_t * pxIndex; //列表項(xiàng)索引指針
	MiniListItem_t xListEnd; //列表最后一個(gè)列表項(xiàng)
}List_t;

typedef struct xMINI_LIST_ITEM
{
	TickType_t xItemValue;//輔助值，用作節(jié)點(diǎn)做順序排序
	struct xLIST_ITEM * pxNext;//后繼指針
	struct xLIST_ITEM * pxPrevious;//前驅(qū)指針
}MiniListItem_t;

void vListInitialise(List_t * const pxList)
{
	//列表索引指向最后一個(gè)節(jié)點(diǎn)
	pxList->pxIndex = (ListItem_t *) &(pxList->xListEnd);
	//將列表最后一個(gè)節(jié)點(diǎn)輔助值設(shè)置為最大，確保該節(jié)點(diǎn)是最后節(jié)點(diǎn)
	pxList->xListEnd.xItemValue = portMAX_DELAY;
	//將最后一個(gè)節(jié)點(diǎn)的前驅(qū)和后繼指針指向自己，表示列表此時(shí)為空
	pxList->xListEnd.pxNext     = (ListItem_t*) &(pxList->xListEnd);
	pxList->xListEnd.pxPrevious = (ListItem_t*) &(pxList->xListEnd);	
	//表示此時(shí)列表中有0個(gè)列表項(xiàng)
	pxList->uxNumberOfItems = (UBaseType_t)0U;
}

void vListInsertEnd(List_t * const pxList,ListItem_t * const pxNewListItem)
{
    //取列表項(xiàng)索引指針，此時(shí)該指針指向最后一個(gè)節(jié)點(diǎn)
	ListItem_t * const pxIndex = pxList->pxIndex;
	//新插入的列表項(xiàng)前驅(qū)指針指向最后一個(gè)節(jié)點(diǎn)
	pxNewListItem->pxNext = pxIndex;
	//新插入的列表項(xiàng)的后繼指針也指向最后一個(gè)節(jié)點(diǎn)
	pxNewListItem->pxPrevious = pxIndex->pxPrevious;
	//列表的最后一個(gè)節(jié)點(diǎn)的后繼指針指向新插入的列表項(xiàng)
	pxNewListItem->pxPrevious->pxNext = pxNewListItem;
	//列表的最后一個(gè)節(jié)點(diǎn)的前驅(qū)指針也指向新插入的列表項(xiàng)
	pxIndex->pxPrevious = pxNewListItem;
	//新插入的列表項(xiàng)是輸入該列表的
	pxNewListItem->pvContainer = (void*) pxList;
	 //該列表中列表項(xiàng)數(shù)目+1
	(pxList->uxNumberOfItems)++;
}

void vListInsert(List_t * const pxList,ListItem_t * const pxNewListItem)
{
	ListItem_t *pxIterator;
	//獲取新插入列表項(xiàng)的輔助值
	const TickType_t xValueOfInsertion = pxNewListItem->xItemValue;
	if(xValueOfInsertion == portMAX_DELAY)
	{
			pxIterator = pxList->xListEnd.pxPrevious;
	}
	else
	{
			for(pxIterator = (ListItem_t*) &(pxList->xListEnd);
		      pxIterator->pxNext->xItemValue <=xValueOfInsertion ;
		      pxIterator = pxIterator->pxNext)
			{
			}
	}
	//對(duì)于下圖此時(shí)pxIterator指向List_item1
	//此時(shí)pxIterator->pxNext是List_item3地址
	pxNewListItem->pxNext = pxIterator->pxNext;//1
	//pxNewListItem->pxNext->pxPrevious是item3的前驅(qū)指針指向新列表項(xiàng)item2
	pxNewListItem->pxNext->pxPrevious = pxNewListItem;
	//新列表項(xiàng)item2的前驅(qū)指針指向pxIterator即item1
	pxNewListItem->pxPrevious = pxIterator;
	//pxIterator即item1的后繼指向新列表項(xiàng)item2
	pxIterator->pxNext = pxNewListItem;
	pxNewListItem->pvContainer = (void*) pxList;
	(pxList->uxNumberOfItems)++;
}

UBaseType_t uxListRemove(ListItem_t * const pxItemToRemove)
{
	//獲取列表項(xiàng)所在列表
	List_t * const pxList = (List_t*)pxItemToRemove->pvContainer;
	//把要?jiǎng)h除的列表項(xiàng)從列表中摘出來
	pxItemToRemove->pxNext->pxPrevious = pxItemToRemove->pxPrevious;
	pxItemToRemove->pxPrevious->pxNext = pxItemToRemove->pxNext;
	if(pxList->pxIndex == pxItemToRemove)
	{
			pxList->pxIndex = pxItemToRemove->pxPrevious;
	}
	//該列表項(xiàng)所有者置空
	pxItemToRemove->pvContainer = NULL;
	(pxList->uxNumberOfItems)--;
	return pxList->uxNumberOfItems;
}

List_t List_Test;
ListItem_t List_Item1;
ListItem_t List_Item2;
ListItem_t List_Item3;
int main(void)
{
	//初始化列表
    vListInitialise(&List_Test);
    //初始化列表項(xiàng)
    vListInitialiseItem(&List_Item1);
	List_Item1.xItemValue = 1;
    vListInitialiseItem(&List_Item2);
	List_Item2.xItemValue = 2;
    vListInitialiseItem(&List_Item3);
	List_Item3.xItemValue = 3;
    vListInsert(&List_Test,&List_Item1);
	vListInsert(&List_Test,&List_Item3);
	vListInsert(&List_Test,&List_Item2);
	while(1);
}