usbh_list.h

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#ifndef _LIST_H_
#define _LIST_H_
 
/*
 * Simple doubly linked list implementation.
 *
 * Some of the internal functions ("__xxx") are useful when
 * manipulating whole lists rather than single entries, as
 * sometimes we already know the next/prev entries and we can
 * generate better code by using them directly rather than
 * using the generic single-entry routines.
 */
 
typedef struct list_head
{
    struct list_head *next, *prev;
} USB_LIST_T;
 
#define LIST_HEAD_INIT(name) { &(name), &(name) }
 
#define LIST_HEAD(name) \
    USB_LIST_T name = LIST_HEAD_INIT(name)
 
#define INIT_LIST_HEAD(ptr) do { \
    (ptr)->next = (ptr); (ptr)->prev = (ptr); \
} while (0)
 
/*
 * Insert a new entry between two known consecutive entries.
 *
 * This is only for internal list manipulation where we know
 * the prev/next entries already!
 */
 
static __inline void __list_add(USB_LIST_T * new,
                                USB_LIST_T * prev,
                                USB_LIST_T * next)
{
    next->prev = new;
    new->next = next;
    new->prev = prev;
    prev->next = new;
}
 
static __inline void list_add(USB_LIST_T *new, USB_LIST_T *head)
{
    __list_add(new, head, head->next);
}
 
static __inline void list_add_tail(USB_LIST_T *new, USB_LIST_T *head)
{
    __list_add(new, head->prev, head);
}
 
/*
 * Delete a list entry by making the prev/next entries
 * point to each other.
 *
 * This is only for internal list manipulation where we know
 * the prev/next entries already!
 */
static __inline void __list_del(USB_LIST_T * prev,
                                USB_LIST_T * next)
{
    next->prev = prev;
    prev->next = next;
}
 
static __inline void list_del(USB_LIST_T *entry)
{
    __list_del(entry->prev, entry->next);
}
 
static __inline void list_del_init(USB_LIST_T *entry)
{
    __list_del(entry->prev, entry->next);
    INIT_LIST_HEAD(entry);
}
 
static __inline int list_empty(USB_LIST_T *head)
{
    return head->next == head;
}
 
static __inline void list_splice(USB_LIST_T *list, USB_LIST_T *head)
{
    USB_LIST_T *first = list->next;
 
    if(first != list)
    {
        USB_LIST_T *last = list->prev;
        USB_LIST_T *at = head->next;
 
        first->prev = head;
        head->next = first;
 
        last->next = at;
        at->prev = last;
    }
}
 
#define list_entry(ptr, type, member) \
    ((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member)))
 
#define list_for_each(pos, head) \
    for (pos = (head)->next; pos != (head); pos = pos->next)
 
 
#define list_for_each_safe(pos, n, head) \
    for (pos = (head)->next, n = pos->next; pos != (head); \
        pos = n, n = pos->next)
 
 
static __inline void __list_splice(struct list_head *list, struct list_head *head)
{
    struct list_head *first = list->next;
    struct list_head *last = list->prev;
    struct list_head *at = head->next;
 
    first->prev = head;
    head->next = first;
 
    last->next = at;
    at->prev = last;
}
 
 
static __inline void list_move_tail(struct list_head *list,  struct list_head *head)
{
    __list_del(list->prev, list->next);
    list_add_tail(list, head);
}
 
 
static __inline void list_move(struct list_head *list, struct list_head *head)
{
    __list_del(list->prev, list->next);
    list_add(list, head);
}
 
 
#endif  /* _LIST_H_ */