学步园

//已知链表地址,怎么得到链表所属的结构体的地址.

pOpenHead = CONTAINING_RECORD( pEntry, HW_OPEN_INFO, llist);

//链表类型为llist,所属上层结构体为HW_OPEN_INFO,pEntry就是已分配内存的链表的地址

/*
#define CONTAINING_RECORD(address, type, field) ((type *)( \
                          (LPBYTE)(address) - \
                          (LPBYTE)(&((type *)0)->field)))
*/
 

/*
typedef struct __HW_OPEN_INFO {
    PHW_INDEP_INFO  pSerialHead;    // @field Pointer back to our HW_INDEP_INFO
    DWORD	        AccessCode;     // @field What permissions was this opened with
    DWORD	        ShareMode;      // @field What Share Mode was this opened with
    DWORD           StructUsers;    // @field Count of threads currently using struct.
	COMM_EVENTS		CommEvents;		// @field Contains all info for serial event handling
    LIST_ENTRY      llist;          // @field Linked list of OPEN_INFOs
	} HW_OPEN_INFO, *PHW_OPEN_INFO;

*/

//链表怎么初始化和 插入的: 答链表头必须要用InitializeListHead初始化,要插入的节点不需要,

typedef struct _LIST_ENTRY {
    struct _LIST_ENTRY  * Flink;
 int a;
    struct _LIST_ENTRY  * Blink;
} LIST_ENTRY,*PLIST_ENTRY;

EX_ListHead是一个_LIST_ENTRY结构体变量,那么EX_ListHead.Flink和EX_ListHead.Flink->Blink代表什么?

答:EX_ListHead.Flink和代表一个_LIST_ENTRY类型的指针,这个指针站4个字节位于EX_ListHead变量的空间内,

EX_ListHead.Flink->Blink,如果令EX_ListHead.Flink=X, 那么EX_ListHead.Flink->Blink相当于X.Blink

//定义2个变量

LIST_ENTRY      OpenList;       // @field Head of linked list of OPEN_INFOs  
LIST_ENTRY llist;

LIST_ENTRY llist2;

    InitializeListHead( &OpenList );
    InsertHeadList(&OpenList,&llist);

//他们2个关系如图

    InsertHeadList(&OpenList,&llist2);

//他们3个关系如图:

附录:

#define InitializeListHead(ListHead) \
    ((ListHead)->Flink = (ListHead)->Blink = (ListHead) )

#define IsListEmpty(ListHead) \
    (( ((ListHead)->Flink == (ListHead)) ? TRUE : FALSE ) )

#define RemoveHeadList(ListHead) \
    (ListHead)->Flink;\
    {\
    PLIST_ENTRY FirstEntry;\
    FirstEntry = (ListHead)->Flink;\
    FirstEntry->Flink->Blink = (ListHead);\
    (ListHead)->Flink = FirstEntry->Flink;\
    }

#define RemoveEntryList(Entry) do {\
    PLIST_ENTRY _EX_Entry;\
    _EX_Entry = (Entry);\
    _EX_Entry->Blink->Flink = _EX_Entry->Flink;\
    _EX_Entry->Flink->Blink = _EX_Entry->Blink;\
    } while(0);

_inline
PLIST_ENTRY
RemoveTailList(PLIST_ENTRY ListHead)
{
    PLIST_ENTRY _Tail_Entry;
    _Tail_Entry = ListHead->Blink;
    RemoveEntryList(_Tail_Entry);
    return _Tail_Entry;
}

#define InsertTailList(_ListHead,_Entry) do {\
      PLIST_ENTRY _EX_ListHead = _ListHead; \
      PLIST_ENTRY _EX_Blink = _EX_ListHead->Blink; \
      (_Entry)->Flink = _EX_ListHead; \
      (_Entry)->Blink = _EX_Blink; \
      _EX_Blink->Flink = _Entry; \
      _EX_ListHead->Blink = _Entry; \
    } while(0);

#define InsertHeadList(_ListHead,_Entry) do {\
      PLIST_ENTRY _EX_ListHead = _ListHead; \
      PLIST_ENTRY _EX_Flink = _EX_ListHead->Flink; \
      (_Entry)->Flink = _EX_Flink; \
      (_Entry)->Blink = _EX_ListHead; \
      _EX_Flink->Blink = _Entry; \
      _EX_ListHead->Flink = _Entry; \
    } while (0);