#ifndef EXEC_LISTS_H
#define EXEC_LISTS_H
/*
**      $Filename: exec/lists.h $
**      $Release: 2.04 Includes, V37.4 $
**      $Revision: 36.10 $
**      $Date: 91/03/15 $
**
**      Definitions and macros for use with Exec lists
**
**      (C) Copyright 1985-1999 Amiga, Inc.
**          All Rights Reserved
*/

#ifndef EXEC_NODES_H
#include "exec/nodes.h"
#endif /* EXEC_NODES_H */

/*
 *  Full featured list header.
 */
struct List {
   struct  Node *lh_Head;
   struct  Node *lh_Tail;
   struct  Node *lh_TailPred;
   UBYTE   lh_Type;
   UBYTE   l_pad;
};      /* word aligned */

/*
 * Minimal List Header - no type checking
 */
struct MinList {
   struct  MinNode *mlh_Head;
   struct  MinNode *mlh_Tail;
   struct  MinNode *mlh_TailPred;
};      /* longword aligned */


/*
 *      Check for the presence of any nodes on the given list.  These
 *      macros are even safe to use on lists that are modified by other
 *      tasks.  However; if something is simultaneously changing the
 *      list, the result of the test is unpredictable.
 *
 *      Unless you first arbitrated for ownership of the list, you can't
 *      _depend_ on the contents of the list.  Nodes might have been added
 *      or removed during or after the macro executes.
 *
 *              if( IsListEmpty(list) )         printf("List is empty\n");
 */
#define IsListEmpty(x) \
        ( ((x)->lh_TailPred) == (struct Node *)(x) )

#define IsMsgPortEmpty(x) \
        ( ((x)->mp_MsgList.lh_TailPred) == (struct Node *)(&(x)->mp_MsgList) )


#endif  /* EXEC_LISTS_H */