Line data    Source code

       1             : /*
       2             :  * Doubly-linked list
       3             :  * Copyright (c) 2009, Jouni Malinen <j@w1.fi>
       4             :  *
       5             :  * This software may be distributed under the terms of the BSD license.
       6             :  * See README for more details.
       7             :  */
       8             : 
       9             : #ifndef LIST_H
      10             : #define LIST_H
      11             : 
      12             : /**
      13             :  * struct dl_list - Doubly-linked list
      14             :  */
      15             : struct dl_list {
      16             :         struct dl_list *next;
      17             :         struct dl_list *prev;
      18             : };
      19             : 
      20       12607 : static inline void dl_list_init(struct dl_list *list)
      21             : {
      22       12607 :         list->next = list;
      23       12607 :         list->prev = list;
      24       12607 : }
      25             : 
      26     2869762 : static inline void dl_list_add(struct dl_list *list, struct dl_list *item)
      27             : {
      28     2869762 :         item->next = list->next;
      29     2869762 :         item->prev = list;
      30     2869762 :         list->next->prev = item;
      31     2869762 :         list->next = item;
      32     2869762 : }
      33             : 
      34       22637 : static inline void dl_list_add_tail(struct dl_list *list, struct dl_list *item)
      35             : {
      36       22637 :         dl_list_add(list->prev, item);
      37       22637 : }
      38             : 
      39     2869701 : static inline void dl_list_del(struct dl_list *item)
      40             : {
      41     2869701 :         item->next->prev = item->prev;
      42     2869701 :         item->prev->next = item->next;
      43     2869701 :         item->next = NULL;
      44     2869701 :         item->prev = NULL;
      45     2869701 : }
      46             : 
      47     2898109 : static inline int dl_list_empty(struct dl_list *list)
      48             : {
      49     2898109 :         return list->next == list;
      50             : }
      51             : 
      52         204 : static inline unsigned int dl_list_len(struct dl_list *list)
      53             : {
      54             :         struct dl_list *item;
      55         204 :         int count = 0;
      56        1047 :         for (item = list->next; item != list; item = item->next)
      57         843 :                 count++;
      58         204 :         return count;
      59             : }
      60             : 
      61             : #ifndef offsetof
      62             : #define offsetof(type, member) ((long) &((type *) 0)->member)
      63             : #endif
      64             : 
      65             : #define dl_list_entry(item, type, member) \
      66             :         ((type *) ((char *) item - offsetof(type, member)))
      67             : 
      68             : #define dl_list_first(list, type, member) \
      69             :         (dl_list_empty((list)) ? NULL : \
      70             :          dl_list_entry((list)->next, type, member))
      71             : 
      72             : #define dl_list_last(list, type, member) \
      73             :         (dl_list_empty((list)) ? NULL : \
      74             :          dl_list_entry((list)->prev, type, member))
      75             : 
      76             : #define dl_list_for_each(item, list, type, member) \
      77             :         for (item = dl_list_entry((list)->next, type, member); \
      78             :              &item->member != (list); \
      79             :              item = dl_list_entry(item->member.next, type, member))
      80             : 
      81             : #define dl_list_for_each_safe(item, n, list, type, member) \
      82             :         for (item = dl_list_entry((list)->next, type, member), \
      83             :                      n = dl_list_entry(item->member.next, type, member); \
      84             :              &item->member != (list); \
      85             :              item = n, n = dl_list_entry(n->member.next, type, member))
      86             : 
      87             : #define dl_list_for_each_reverse(item, list, type, member) \
      88             :         for (item = dl_list_entry((list)->prev, type, member); \
      89             :              &item->member != (list); \
      90             :              item = dl_list_entry(item->member.prev, type, member))
      91             : 
      92             : #define DEFINE_DL_LIST(name) \
      93             :         struct dl_list name = { &(name), &(name) }
      94             : 
      95             : #endif /* LIST_H */