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             : #define DL_LIST_HEAD_INIT(l) { &(l), &(l) }
      21             : 
      22       24585 : static inline void dl_list_init(struct dl_list *list)
      23             : {
      24       24585 :         list->next = list;
      25       24585 :         list->prev = list;
      26       24585 : }
      27             : 
      28     4797681 : static inline void dl_list_add(struct dl_list *list, struct dl_list *item)
      29             : {
      30     4797681 :         item->next = list->next;
      31     4797681 :         item->prev = list;
      32     4797681 :         list->next->prev = item;
      33     4797681 :         list->next = item;
      34     4797681 : }
      35             : 
      36       35175 : static inline void dl_list_add_tail(struct dl_list *list, struct dl_list *item)
      37             : {
      38       35175 :         dl_list_add(list->prev, item);
      39       35175 : }
      40             : 
      41     4797600 : static inline void dl_list_del(struct dl_list *item)
      42             : {
      43     4797600 :         item->next->prev = item->prev;
      44     4797600 :         item->prev->next = item->next;
      45     4797600 :         item->next = NULL;
      46     4797600 :         item->prev = NULL;
      47     4797600 : }
      48             : 
      49     5498709 : static inline int dl_list_empty(struct dl_list *list)
      50             : {
      51     5498709 :         return list->next == list;
      52             : }
      53             : 
      54        1061 : static inline unsigned int dl_list_len(struct dl_list *list)
      55             : {
      56             :         struct dl_list *item;
      57        1061 :         int count = 0;
      58        2893 :         for (item = list->next; item != list; item = item->next)
      59        1832 :                 count++;
      60        1061 :         return count;
      61             : }
      62             : 
      63             : #ifndef offsetof
      64             : #define offsetof(type, member) ((long) &((type *) 0)->member)
      65             : #endif
      66             : 
      67             : #define dl_list_entry(item, type, member) \
      68             :         ((type *) ((char *) item - offsetof(type, member)))
      69             : 
      70             : #define dl_list_first(list, type, member) \
      71             :         (dl_list_empty((list)) ? NULL : \
      72             :          dl_list_entry((list)->next, type, member))
      73             : 
      74             : #define dl_list_last(list, type, member) \
      75             :         (dl_list_empty((list)) ? NULL : \
      76             :          dl_list_entry((list)->prev, type, member))
      77             : 
      78             : #define dl_list_for_each(item, list, type, member) \
      79             :         for (item = dl_list_entry((list)->next, type, member); \
      80             :              &item->member != (list); \
      81             :              item = dl_list_entry(item->member.next, type, member))
      82             : 
      83             : #define dl_list_for_each_safe(item, n, list, type, member) \
      84             :         for (item = dl_list_entry((list)->next, type, member), \
      85             :                      n = dl_list_entry(item->member.next, type, member); \
      86             :              &item->member != (list); \
      87             :              item = n, n = dl_list_entry(n->member.next, type, member))
      88             : 
      89             : #define dl_list_for_each_reverse(item, list, type, member) \
      90             :         for (item = dl_list_entry((list)->prev, type, member); \
      91             :              &item->member != (list); \
      92             :              item = dl_list_entry(item->member.prev, type, member))
      93             : 
      94             : #define DEFINE_DL_LIST(name) \
      95             :         struct dl_list name = { &(name), &(name) }
      96             : 
      97             : #endif /* LIST_H */