LXR linux/scripts/kconfig/list.h

   1#ifndef LIST_H
   2#define LIST_H
   3
   4/*
   5 * Copied from include/linux/...
   6 */
   7
   8#undef offsetof
   9#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
  10
  11/**
  12 * container_of - cast a member of a structure out to the containing structure
  13 * @ptr:        the pointer to the member.
  14 * @type:       the type of the container struct this is embedded in.
  15 * @member:     the name of the member within the struct.
  16 *
  17 */
  18#define container_of(ptr, type, member) ({                      \
  19        const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
  20        (type *)( (char *)__mptr - offsetof(type,member) );})
  21
  22
  23struct list_head {
  24        struct list_head *next, *prev;
  25};
  26
  27
  28#define LIST_HEAD_INIT(name) { &(name), &(name) }
  29
  30#define LIST_HEAD(name) \
  31        struct list_head name = LIST_HEAD_INIT(name)
  32
  33/**
  34 * list_entry - get the struct for this entry
  35 * @ptr:        the &struct list_head pointer.
  36 * @type:       the type of the struct this is embedded in.
  37 * @member:     the name of the list_head within the struct.
  38 */
  39#define list_entry(ptr, type, member) \
  40        container_of(ptr, type, member)
  41
  42/**
  43 * list_for_each_entry  -       iterate over list of given type
  44 * @pos:        the type * to use as a loop cursor.
  45 * @head:       the head for your list.
  46 * @member:     the name of the list_head within the struct.
  47 */
  48#define list_for_each_entry(pos, head, member)                          \
  49        for (pos = list_entry((head)->next, typeof(*pos), member);      \
  50             &pos->member != (head);    \
  51             pos = list_entry(pos->member.next, typeof(*pos), member))
  52
  53/**
  54 * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
  55 * @pos:        the type * to use as a loop cursor.
  56 * @n:          another type * to use as temporary storage
  57 * @head:       the head for your list.
  58 * @member:     the name of the list_head within the struct.
  59 */
  60#define list_for_each_entry_safe(pos, n, head, member)                  \
  61        for (pos = list_entry((head)->next, typeof(*pos), member),      \
  62                n = list_entry(pos->member.next, typeof(*pos), member); \
  63             &pos->member != (head);                                    \
  64             pos = n, n = list_entry(n->member.next, typeof(*n), member))
  65
  66/**
  67 * list_empty - tests whether a list is empty
  68 * @head: the list to test.
  69 */
  70static inline int list_empty(const struct list_head *head)
  71{
  72        return head->next == head;
  73}
  74
  75/*
  76 * Insert a new entry between two known consecutive entries.
  77 *
  78 * This is only for internal list manipulation where we know
  79 * the prev/next entries already!
  80 */
  81static inline void __list_add(struct list_head *_new,
  82                              struct list_head *prev,
  83                              struct list_head *next)
  84{
  85        next->prev = _new;
  86        _new->next = next;
  87        _new->prev = prev;
  88        prev->next = _new;
  89}
  90
  91/**
  92 * list_add_tail - add a new entry
  93 * @new: new entry to be added
  94 * @head: list head to add it before
  95 *
  96 * Insert a new entry before the specified head.
  97 * This is useful for implementing queues.
  98 */
  99static inline void list_add_tail(struct list_head *_new, struct list_head *head)
 100{
 101        __list_add(_new, head->prev, head);
 102}
 103
 104/*
 105 * Delete a list entry by making the prev/next entries
 106 * point to each other.
 107 *
 108 * This is only for internal list manipulation where we know
 109 * the prev/next entries already!
 110 */
 111static inline void __list_del(struct list_head *prev, struct list_head *next)
 112{
 113        next->prev = prev;
 114        prev->next = next;
 115}
 116
 117#define LIST_POISON1  ((void *) 0x00100100)
 118#define LIST_POISON2  ((void *) 0x00200200)
 119/**
 120 * list_del - deletes entry from list.
 121 * @entry: the element to delete from the list.
 122 * Note: list_empty() on entry does not return true after this, the entry is
 123 * in an undefined state.
 124 */
 125static inline void list_del(struct list_head *entry)
 126{
 127        __list_del(entry->prev, entry->next);
 128        entry->next = (struct list_head*)LIST_POISON1;
 129        entry->prev = (struct list_head*)LIST_POISON2;
 130}
 131#endif
 132