#define xbt_fifo_getFirstitem(l) ((l)?(l)->head:NULL)
#define xbt_fifo_getNextitem(i) ((i)?(i)->next:NULL)
#define xbt_fifo_getPrevitem(i) ((i)?(i)->prev:NULL)
#define xbt_fifo_getItemcontent(i) ((i)?(i)->content:NULL)
#define xbt_fifo_Itemcontent(i) ((i)->content)
#define xbt_fifo_setItemcontent(i,v) (i->content=v)
#define xbt_fifo_getFirstitem(l) ((l)?(l)->head:NULL)
#define xbt_fifo_getNextitem(i) ((i)?(i)->next:NULL)
#define xbt_fifo_getPrevitem(i) ((i)?(i)->prev:NULL)
#define xbt_fifo_getItemcontent(i) ((i)?(i)->content:NULL)
#define xbt_fifo_Itemcontent(i) ((i)->content)
#define xbt_fifo_setItemcontent(i,v) (i->content=v)