target/linux/s3c24xx/files-2.6.30/drivers/ar6000/include/dl_list.h

   1 /*
   2  *
   3  * Double-link list definitions (adapted from Atheros SDIO stack)
   4  *
   5  * Copyright (c) 2007 Atheros Communications Inc.
   6  * All rights reserved.
   7  *
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License version 2 as
  11  *  published by the Free Software Foundation;
  12  *
  13  *  Software distributed under the License is distributed on an "AS
  14  *  IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
  15  *  implied. See the License for the specific language governing
  16  *  rights and limitations under the License.
  17  *
  18  *
  19  *
  20  */
  21 #ifndef __DL_LIST_H___
  22 #define __DL_LIST_H___
  23
  24 #define A_CONTAINING_STRUCT(address, struct_type, field_name)\
  25             ((struct_type *)((A_UINT32)(address) - (A_UINT32)(&((struct_type *)0)->field_name)))
  26
  27 /* list functions */
  28 /* pointers for the list */
  29 typedef struct _DL_LIST {
  30     struct _DL_LIST *pPrev;
  31     struct _DL_LIST *pNext;
  32 }DL_LIST, *PDL_LIST;
  33 /*
  34  * DL_LIST_INIT , initialize doubly linked list
  35 */
  36 #define DL_LIST_INIT(pList)\
  37     {(pList)->pPrev = pList; (pList)->pNext = pList;}
  38
  39 #define DL_LIST_IS_EMPTY(pList) (((pList)->pPrev == (pList)) && ((pList)->pNext == (pList)))
  40 #define DL_LIST_GET_ITEM_AT_HEAD(pList) (pList)->pNext
  41 #define DL_LIST_GET_ITEM_AT_TAIL(pList) (pList)->pPrev
  42 /*
  43  * ITERATE_OVER_LIST pStart is the list, pTemp is a temp list member
  44  * NOT: do not use this function if the items in the list are deleted inside the
  45  * iteration loop
  46 */
  47 #define ITERATE_OVER_LIST(pStart, pTemp) \
  48     for((pTemp) =(pStart)->pNext; pTemp != (pStart); (pTemp) = (pTemp)->pNext)
  49
  50
  51 /* safe iterate macro that allows the item to be removed from the list
  52  * the iteration continues to the next item in the list
  53  */
  54 #define ITERATE_OVER_LIST_ALLOW_REMOVE(pStart,pItem,st,offset)  \
  55 {                                                       \
  56     PDL_LIST  pTemp;                                     \
  57     pTemp = (pStart)->pNext;                            \
  58     while (pTemp != (pStart)) {                         \
  59         (pItem) = A_CONTAINING_STRUCT(pTemp,st,offset);   \
  60          pTemp = pTemp->pNext;                          \
  61
  62 #define ITERATE_END }}
  63
  64 /*
  65  * DL_ListInsertTail - insert pAdd to the end of the list
  66 */
  67 static INLINE PDL_LIST DL_ListInsertTail(PDL_LIST pList, PDL_LIST pAdd) {
  68         /* insert at tail */
  69     pAdd->pPrev = pList->pPrev;
  70     pAdd->pNext = pList;
  71     pList->pPrev->pNext = pAdd;
  72     pList->pPrev = pAdd;
  73     return pAdd;
  74 }
  75
  76 /*
  77  * DL_ListInsertHead - insert pAdd into the head of the list
  78 */
  79 static INLINE PDL_LIST DL_ListInsertHead(PDL_LIST pList, PDL_LIST pAdd) {
  80         /* insert at head */
  81     pAdd->pPrev = pList;
  82     pAdd->pNext = pList->pNext;
  83     pList->pNext->pPrev = pAdd;
  84     pList->pNext = pAdd;
  85     return pAdd;
  86 }
  87
  88 #define DL_ListAdd(pList,pItem) DL_ListInsertHead((pList),(pItem))
  89 /*
  90  * DL_ListRemove - remove pDel from list
  91 */
  92 static INLINE PDL_LIST DL_ListRemove(PDL_LIST pDel) {
  93     pDel->pNext->pPrev = pDel->pPrev;
  94     pDel->pPrev->pNext = pDel->pNext;
  95         /* point back to itself just to be safe, incase remove is called again */
  96     pDel->pNext = pDel;
  97     pDel->pPrev = pDel;
  98     return pDel;
  99 }
 100
 101 /*
 102  * DL_ListRemoveItemFromHead - get a list item from the head
 103 */
 104 static INLINE PDL_LIST DL_ListRemoveItemFromHead(PDL_LIST pList) {
 105     PDL_LIST pItem = NULL;
 106     if (pList->pNext != pList) {
 107         pItem = pList->pNext;
 108             /* remove the first item from head */
 109         DL_ListRemove(pItem);
 110     }
 111     return pItem;
 112 }
 113
 114 #endif /* __DL_LIST_H___ */