list.h

#ifndef FIRM_ADT_LIST_H
#define FIRM_ADT_LIST_H

#include <stdlib.h>

#include "../begin.h"

typedef struct list_head list_head;

#define LIST_HEAD_INIT(name) { &(name), &(name) }

#define LIST_HEAD(name) \
    struct list_head name = LIST_HEAD_INIT(name)

#define INIT_LIST_HEAD(ptr) do { \
    (ptr)->next = (ptr); (ptr)->prev = (ptr); \
} while (0)

struct list_head {
    struct list_head *next, *prev;
};

#define _list_offsetof(type,member) \
  ((char *) &(((type *) 0)->member) - (char *) 0)

#define _list_container_of(ptr, type, member) \
    ((type *) ((char *) (ptr) - _list_offsetof(type, member)))

static inline void __list_add(struct list_head *new_node,
                              struct list_head *prev,
                              struct list_head *next)
{
    next->prev = new_node;
    new_node->next = next;
    new_node->prev = prev;
    prev->next = new_node;
}

static inline void list_add(struct list_head *new_node, struct list_head *head)
{
    __list_add(new_node, head, head->next);
}

static inline void list_add_tail(struct list_head *new_node, struct list_head *head)
{
    __list_add(new_node, head->prev, head);
}

static inline void __list_del(struct list_head * prev, struct list_head * next)
{
    next->prev = prev;
    prev->next = next;
}

static inline void list_del(struct list_head *entry)
{
    __list_del(entry->prev, entry->next);
    entry->next = NULL;
    entry->prev = NULL;
}


static inline void list_del_init(struct list_head *entry)
{
    __list_del(entry->prev, entry->next);
    INIT_LIST_HEAD(entry);
}

static inline void list_move(struct list_head *list, struct list_head *head)
{
        __list_del(list->prev, list->next);
        list_add(list, head);
}

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 int list_empty(const struct list_head *head)
{
    return head->next == head;
}

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_splice(struct list_head *list, struct list_head *head)
{
    if (!list_empty(list))
        __list_splice(list, head);
}

static inline void list_splice_init(struct list_head *list,
                    struct list_head *head)
{
    if (!list_empty(list)) {
        __list_splice(list, head);
        INIT_LIST_HEAD(list);
    }
}

#define list_entry(ptr, type, member) \
    _list_container_of(ptr, type, member)

#define list_for_each(pos, head) \
    for (pos = (head)->next; pos != (head); pos = pos->next)

#define list_for_each_prev(pos, head) \
    for (pos = (head)->prev; pos != (head); pos = pos->prev)

#define list_for_each_safe(pos, n, head) \
    for (pos = (head)->next, n = pos->next; pos != (head); \
        pos = n, n = pos->next)

#define list_for_each_entry(type, pos, head, member)    \
    for (type *pos = list_entry((head)->next, type, member); \
         &pos->member != (head);                        \
         pos = list_entry(pos->member.next, type, member))

#define list_for_each_entry_reverse(type, pos, head, member) \
    for (type *pos = list_entry((head)->prev, type, member); \
         &pos->member != (head);                             \
         pos = list_entry(pos->member.prev, type, member))


#define list_for_each_entry_safe(type, pos, n, head, member) \
    for (type *pos = list_entry((head)->next, type, member), \
              *n   = list_entry(pos->member.next, type, member); \
         &pos->member != (head);                             \
         pos = n, n = list_entry(n->member.next, type, member))

#include "../end.h"

#endif