LXR linux/tools/usb/usbip/libsrc/list.h

   1#ifndef _LIST_H
   2#define _LIST_H
   3
   4/* Stripped down implementation of linked list taken
   5 * from the Linux Kernel.
   6 */
   7
   8/*
   9 * Simple doubly linked list implementation.
  10 *
  11 * Some of the internal functions ("__xxx") are useful when
  12 * manipulating whole lists rather than single entries, as
  13 * sometimes we already know the next/prev entries and we can
  14 * generate better code by using them directly rather than
  15 * using the generic single-entry routines.
  16 */
  17
  18struct list_head {
  19        struct list_head *next, *prev;
  20};
  21
  22#define LIST_HEAD_INIT(name) { &(name), &(name) }
  23
  24#define LIST_HEAD(name) \
  25        struct list_head name = LIST_HEAD_INIT(name)
  26
  27static inline void INIT_LIST_HEAD(struct list_head *list)
  28{
  29        list->next = list;
  30        list->prev = list;
  31}
  32
  33/*
  34 * Insert a new entry between two known consecutive entries.
  35 *
  36 * This is only for internal list manipulation where we know
  37 * the prev/next entries already!
  38 */
  39static inline void __list_add(struct list_head *new,
  40                              struct list_head *prev,
  41                              struct list_head *next)
  42{
  43        next->prev = new;
  44        new->next = next;
  45        new->prev = prev;
  46        prev->next = new;
  47}
  48
  49/**
  50 * list_add - add a new entry
  51 * @new: new entry to be added
  52 * @head: list head to add it after
  53 *
  54 * Insert a new entry after the specified head.
  55 * This is good for implementing stacks.
  56 */
  57static inline void list_add(struct list_head *new, struct list_head *head)
  58{
  59        __list_add(new, head, head->next);
  60}
  61
  62/*
  63 * Delete a list entry by making the prev/next entries
  64 * point to each other.
  65 *
  66 * This is only for internal list manipulation where we know
  67 * the prev/next entries already!
  68 */
  69static inline void __list_del(struct list_head * prev, struct list_head * next)
  70{
  71        next->prev = prev;
  72        prev->next = next;
  73}
  74
  75#define POISON_POINTER_DELTA 0
  76#define LIST_POISON1  ((void *) 0x00100100 + POISON_POINTER_DELTA)
  77#define LIST_POISON2  ((void *) 0x00200200 + POISON_POINTER_DELTA)
  78
  79/**
  80 * list_del - deletes entry from list.
  81 * @entry: the element to delete from the list.
  82 * Note: list_empty() on entry does not return true after this, the entry is
  83 * in an undefined state.
  84 */
  85static inline void __list_del_entry(struct list_head *entry)
  86{
  87        __list_del(entry->prev, entry->next);
  88}
  89
  90static inline void list_del(struct list_head *entry)
  91{
  92        __list_del(entry->prev, entry->next);
  93        entry->next = LIST_POISON1;
  94        entry->prev = LIST_POISON2;
  95}
  96
  97/**
  98 * list_entry - get the struct for this entry
  99 * @ptr:        the &struct list_head pointer.
 100 * @type:       the type of the struct this is embedded in.
 101 * @member:     the name of the list_head within the struct.
 102 */
 103#define list_entry(ptr, type, member) \
 104        container_of(ptr, type, member)
 105/**
 106 * list_for_each        -       iterate over a list
 107 * @pos:        the &struct list_head to use as a loop cursor.
 108 * @head:       the head for your list.
 109 */
 110#define list_for_each(pos, head) \
 111        for (pos = (head)->next; pos != (head); pos = pos->next)
 112
 113/**
 114 * list_for_each_safe - iterate over a list safe against removal of list entry
 115 * @pos:        the &struct list_head to use as a loop cursor.
 116 * @n:          another &struct list_head to use as temporary storage
 117 * @head:       the head for your list.
 118 */
 119#define list_for_each_safe(pos, n, head) \
 120        for (pos = (head)->next, n = pos->next; pos != (head); \
 121                pos = n, n = pos->next)
 122
 123#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
 124
 125/**
 126 * container_of - cast a member of a structure out to the containing structure
 127 * @ptr:        the pointer to the member.
 128 * @type:       the type of the container struct this is embedded in.
 129 * @member:     the name of the member within the struct.
 130 *
 131 */
 132#define container_of(ptr, type, member) ({                      \
 133        const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
 134        (type *)( (char *)__mptr - offsetof(type,member) );})
 135
 136#endif
 137