259 	gen_node *	link;  member
357 #define DECL_DLIST_LINK(entrytype, link)			\  argument
361 } link
363 #define INIT_DLIST(listhead, link)				\  argument
365 	(listhead).link.f = &(listhead);			\
366 	(listhead).link.b = &(listhead);			\
369 #define HEAD_DLIST(listhead, link)				\  argument
371 		(&(listhead) != (listhead).link.f)		\
372 		    ? (listhead).link.f				\
376 #define TAIL_DLIST(listhead, link)				\  argument
378 		(&(listhead) != (listhead).link.b)		\
379 		    ? (listhead).link.b				\
383 #define NEXT_DLIST(listhead, entry, link)			\  argument
385 		(&(listhead) != (entry)->link.f)		\
386 		    ? (entry)->link.f				\
390 #define PREV_DLIST(listhead, entry, link)			\  argument
392 		(&(listhead) != (entry)->link.b)		\
393 		    ? (entry)->link.b				\
397 #define LINK_DLIST(listhead, pentry, link)			\  argument
399 	(pentry)->link.f = (listhead).link.f;			\
400 	(pentry)->link.b = &(listhead);				\
401 	(listhead).link.f->link.b = (pentry);			\
402 	(listhead).link.f = (pentry);				\
405 #define LINK_TAIL_DLIST(listhead, pentry, link)			\  argument
407 	(pentry)->link.b = (listhead).link.b;			\
408 	(pentry)->link.f = &(listhead);				\
409 	(listhead).link.b->link.f = (pentry);			\
410 	(listhead).link.b = (pentry);				\
413 #define UNLINK_DLIST(ptounlink, link)				\  argument
415 	(ptounlink)->link.b->link.f = (ptounlink)->link.f;	\
416 	(ptounlink)->link.f->link.b = (ptounlink)->link.b;	\
417 	MAYBE_Z_LISTS((ptounlink)->link.b);			\
418 	MAYBE_Z_LISTS((ptounlink)->link.f);			\
421 #define ITER_DLIST_BEGIN(listhead, iter, link, entrytype)	\  argument
425 	for ((iter) = (listhead).link.f;			\
427 	     && ((i_dl_nextiter = (iter)->link.f), TRUE);	\
433 #define REV_ITER_DLIST_BEGIN(listhead, iter, link, entrytype)	\  argument
437 	for ((iter) = (listhead).link.b;			\
439 	     && ((i_dl_nextiter = (iter)->link.b), TRUE);	\