29 #define TREE_INIT_NODE(elm, field) do { \  argument
30 	(elm)->field.tn_parent = NULL; \
31 	(elm)->field.tn_first = NULL; \
32 	(elm)->field.tn_last = NULL; \
33 	(elm)->field.tn_younger = NULL; \
34 	(elm)->field.tn_older = NULL; \
37 #define TREE_INSERT_CHILD(treeelm, elm, field) do { \  argument
38 	(elm)->field.tn_parent = (treeelm); \
40 		(treeelm)->field.tn_last->field.tn_younger = (elm); \
41 		(elm)->field.tn_older = (treeelm)->field.tn_last; \
43 	(treeelm)->field.tn_last = (elm); \
45 		(treeelm)->field.tn_first = (elm); \
48 #define TREE_INSERT_YOUNGER(treeelm, elm, field) do { \  argument
49 	(elm)->field.tn_parent = (treeelm)->field.tn_parent; \
51 		(elm)->field.tn_younger = (treeelm)->field.tn_younger; \
52 		(elm)->field.tn_younger->field.tn_older = (elm); \
55 		(treeelm)->field.tn_parent->field.tn_last = (elm); \
56 	(treeelm)->field.tn_younger = (elm); \
57 	(elm)->field.tn_older = (treeelm); \
60 #define TREE_INSERT_OLDER(treeelm, elm, field) do { \  argument
61 	(elm)->field.tn_parent = (treeelm)->field.tn_parent; \
63 		(elm)->field.tn_older = (treeelm)->field.tn_older; \
64 		(elm)->field.tn_older->field.tn_younger = (elm); \
67 		(treeelm)->field.tn_parent->field.tn_first = (elm); \
68 	(treeelm)->field.tn_older = (elm); \
69 	(elm)->field.tn_younger = (treeelm); \
72 #define TREE_DETACH(elm, field) do { \  argument
73 	if ((elm)->field.tn_parent) { \
74 		if ((elm)->field.tn_parent->field.tn_first == (elm)) \
75 			(elm)->field.tn_parent->field.tn_first = (elm)->field.tn_younger; \
76 		if ((elm)->field.tn_parent->field.tn_last == (elm)) \
77 			(elm)->field.tn_parent->field.tn_last = (elm)->field.tn_older; \
79 	if ((elm)->field.tn_younger) \
80 		(elm)->field.tn_younger->field.tn_older = (elm)->field.tn_older; \
81 	if ((elm)->field.tn_older) \
82 		(elm)->field.tn_older->field.tn_younger = (elm)->field.tn_younger; \
83 	(elm)->field.tn_older = (elm)->field.tn_younger = NULL; \
84 	(elm)->field.tn_parent = NULL; \