#include <malloc.h>
#include <assert.h>

typedef struct link_type
{
   struct link_type *next;    /* Next link in the list   */
   void             *entity;  /* Entity owned by link    */
}  link_t;

typedef struct list_type
{
   link_t  *first;           /* First link in the list */
   link_t  *last;            /* Last link in the list  */
   link_t  *current;
}  list_t;

/* Prototypes for list management functions */
/* malloc a new list header and initialize it */

list_t *list_init(
void);

/* Add an element to the end of a list */

void list_add(
list_t *list,
void   *entity);

/* Delete all of the list control structures and */
/* the entities they control                     */

void list_del(
list_t *list);

void list_reset(
list_t *list);

int list_not_end(
list_t *list);

void list_next_link(
list_t *list);

void *list_get_entity(
list_t *list);