/*     
 * list.h
 *
 * x-kernel v3.3
 *
 * Copyright (c) 1993,1991,1990,1996  Arizona Board of Regents
 *
 * $Revision: 1.2 $
 * $Date: 1996/01/29 20:25:55 $
 */


/* A generic singly-linked list */

#ifndef list_h
#define list_h

struct list_entry {
    struct list_entry *next;	/* next element */
};

struct list_head {
    struct list_entry *head;	/* first element */
    struct list_entry *tail;	/* last  element */
};

typedef struct list_head  *list_t;
typedef struct list_entry *list_entry_t;

/*
 * enlist puts "elt" on the "list".
 * delist returns the first element in the "list".
 */

#define enlist(list,elt) enlist_tail(list, elt)
#define delist(list)     delist_head(list)


#ifdef __STDC__

list_entry_t delist_head( list_t );
list_entry_t delist_head_strong( list_t );
list_entry_t delist_tail( list_t );
void         enlist_head( list_t, list_entry_t );
void         enlist_tail( list_t, list_entry_t );
void        list_init( list_t );


#else

list_entry_t delist_head();
list_entry_t delist_head_strong();
list_entry_t delist_tail();
void         enlist_head();
void         enlist_tail();
void         list_init();

#endif /* __STDC__ */

#endif /* list_h */