reactos/drivers/usb/cromwell/linux/list.h

   1 #ifndef _BOOT_LIST_H
   2 #define _BOOT_LIST_H
   3
   4 /*
   5  * Simple doubly linked list implementation.
   6  *
   7  * Some of the internal functions ("__xxx") are useful when
   8  * manipulating whole lists rather than single entries, as
   9  * sometimes we already know the next/prev entries and we can
  10  * generate better code by using them directly rather than
  11  * using the generic single-entry routines.
  12  */
  13
  14 struct list_head {
  15         struct list_head *next, *prev;
  16 };
  17
  18 #define LIST_HEAD_INIT(name) { &(name), &(name) }
  19
  20 #define LIST_HEAD(name) \
  21         struct list_head name = LIST_HEAD_INIT(name)
  22
  23 #define INIT_LIST_HEAD(ptr) do { \
  24         (ptr)->next = (ptr); (ptr)->prev = (ptr); \
  25 } while (0)
  26
  27 /*
  28  * Insert a new entry between two known consecutive entries.
  29  *
  30  * This is only for internal list manipulation where we know
  31  * the prev/next entries already!
  32  */
  33 static inline void __list_add(struct list_head *new,
  34                               struct list_head *prev,
  35                               struct list_head *next)
  36 {
  37         next->prev = new;
  38         new->next = next;
  39         new->prev = prev;
  40         prev->next = new;
  41 }
  42
  43 /**
  44  * list_add - add a new entry
  45  * @new: new entry to be added
  46  * @head: list head to add it after
  47  *
  48  * Insert a new entry after the specified head.
  49  * This is good for implementing stacks.
  50  */
  51 static inline void list_add(struct list_head *new, struct list_head *head)
  52 {
  53         __list_add(new, head, head->next);
  54 }
  55
  56 /**
  57  * list_add_tail - add a new entry
  58  * @new: new entry to be added
  59  * @head: list head to add it before
  60  *
  61  * Insert a new entry before the specified head.
  62  * This is useful for implementing queues.
  63  */
  64 static inline void list_add_tail(struct list_head *new, struct list_head *head)
  65 {
  66         __list_add(new, head->prev, head);
  67 }
  68
  69 /*
  70  * Delete a list entry by making the prev/next entries
  71  * point to each other.
  72  *
  73  * This is only for internal list manipulation where we know
  74  * the prev/next entries already!
  75  */
  76 static inline void __list_del(struct list_head *prev, struct list_head *next)
  77 {
  78         next->prev = prev;
  79         prev->next = next;
  80 }
  81
  82 /**
  83  * list_del - deletes entry from list.
  84  * @entry: the element to delete from the list.
  85  * Note: list_empty on entry does not return true after this, the entry is in an undefined state.
  86  */
  87 static inline void list_del(struct list_head *entry)
  88 {
  89         __list_del(entry->prev, entry->next);
  90         entry->next = (void *) 0;
  91         entry->prev = (void *) 0;
  92 }
  93
  94 /**
  95  * list_del_init - deletes entry from list and reinitialize it.
  96  * @entry: the element to delete from the list.
  97  */
  98 static inline void list_del_init(struct list_head *entry)
  99 {
 100         __list_del(entry->prev, entry->next);
 101         INIT_LIST_HEAD(entry);
 102 }
 103
 104 /**
 105  * list_move - delete from one list and add as another's head
 106  * @list: the entry to move
 107  * @head: the head that will precede our entry
 108  */
 109 static inline void list_move(struct list_head *list, struct list_head *head)
 110 {
 111         __list_del(list->prev, list->next);
 112         list_add(list, head);
 113 }
 114
 115 /**
 116  * list_move_tail - delete from one list and add as another's tail
 117  * @list: the entry to move
 118  * @head: the head that will follow our entry
 119  */
 120 static inline void list_move_tail(struct list_head *list,
 121                                   struct list_head *head)
 122 {
 123         __list_del(list->prev, list->next);
 124         list_add_tail(list, head);
 125 }
 126
 127 /**
 128  * list_empty - tests whether a list is empty
 129  * @head: the list to test.
 130  */
 131 static inline int list_empty(struct list_head *head)
 132 {
 133         return head->next == head;
 134 }
 135
 136 static inline void __list_splice(struct list_head *list,
 137                                  struct list_head *head)
 138 {
 139         struct list_head *first = list->next;
 140         struct list_head *last = list->prev;
 141         struct list_head *at = head->next;
 142
 143         first->prev = head;
 144         head->next = first;
 145
 146         last->next = at;
 147         at->prev = last;
 148 }
 149
 150 /**
 151  * list_splice - join two lists
 152  * @list: the new list to add.
 153  * @head: the place to add it in the first list.
 154  */
 155 static inline void list_splice(struct list_head *list, struct list_head *head)
 156 {
 157         if (!list_empty(list))
 158                 __list_splice(list, head);
 159 }
 160
 161 /**
 162  * list_splice_init - join two lists and reinitialise the emptied list.
 163  * @list: the new list to add.
 164  * @head: the place to add it in the first list.
 165  *
 166  * The list at @list is reinitialised
 167  */
 168 static inline void list_splice_init(struct list_head *list,
 169                                     struct list_head *head)
 170 {
 171         if (!list_empty(list)) {
 172                 __list_splice(list, head);
 173                 INIT_LIST_HEAD(list);
 174         }
 175 }
 176
 177 /**
 178  * list_entry - get the struct for this entry
 179  * @ptr:        the &struct list_head pointer.
 180  * @type:       the type of the struct this is embedded in.
 181  * @member:     the name of the list_struct within the struct.
 182  */
 183 #define list_entry(ptr, type, member) \
 184         ((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member)))
 185
 186 /**
 187  * list_for_each        -       iterate over a list
 188  * @pos:        the &struct list_head to use as a loop counter.
 189  * @head:       the head for your list.
 190  */
 191 #define list_for_each(pos, head) \
 192         for (pos = (head)->next; pos != (head); \
 193                 pos = pos->next)
 194 /**
 195  * list_for_each_prev   -       iterate over a list backwards
 196  * @pos:        the &struct list_head to use as a loop counter.
 197  * @head:       the head for your list.
 198  */
 199 #define list_for_each_prev(pos, head) \
 200         for (pos = (head)->prev; pos != (head); \
 201                 pos = pos->prev)
 202
 203 /**
 204  * list_for_each_safe   -       iterate over a list safe against removal of list entry
 205  * @pos:        the &struct list_head to use as a loop counter.
 206  * @n:          another &struct list_head to use as temporary storage
 207  * @head:       the head for your list.
 208  */
 209 #define list_for_each_safe(pos, n, head) \
 210         for (pos = (head)->next, n = pos->next; pos != (head); \
 211                 pos = n, n = pos->next)
 212
 213 /**
 214  * list_for_each_entry  -       iterate over list of given type
 215  * @pos:        the type * to use as a loop counter.
 216  * @head:       the head for your list.
 217  * @member:     the name of the list_struct within the struct.
 218  */
 219 #define list_for_each_entry(pos, head, member)                          \
 220         for (pos = list_entry((head)->next, typeof(*pos), member)       \
 221              &pos->member != (head);                                    \
 222              pos = list_entry(pos->member.next, typeof(*pos), member))
 223
 224 #endif