list.h

#ifndef LIST_HDR
#define LIST_HDR
#include <stddef.h>

#ifdef __cplusplus
extern "C" {
#endif

typedef struct link_s link_t;
typedef struct list_s list_t;

struct link_s {
    link_t *prev;
    link_t *next;
};

struct list_s {
    link_t *head;
    link_t *tail;
};

void list_init(list_t *list);

void list_push_front(list_t *list, link_t *link);
void list_push_back(list_t *list, link_t *link);
void list_insert_before(list_t *list, link_t *before, link_t *link);
void list_insert_after(list_t *list, link_t *after, link_t *link);

link_t *list_pop_front(list_t *list);
link_t *list_pop_back(list_t *list);

link_t *list_head(const list_t *list);
link_t *list_tail(const list_t *list);

link_t *list_next(const link_t *link);
link_t *list_prev(const link_t *link);

#define list_ref(ELEMENT, TYPE, MEMBER) \
    ((TYPE *)((unsigned char *)(ELEMENT) - offsetof(TYPE, MEMBER)))

#ifdef __cplusplus
}
#endif

#endif