1/*	$NetBSD: twalk.c,v 1.4 2012/03/20 16:38:45 matt Exp $	*/
2
3/*
4 * Tree search generalized from Knuth (6.2.2) Algorithm T just like
5 * the AT&T man page says.
6 *
7 * Written by reading the System V Interface Definition, not the code.
8 *
9 * Totally public domain.
10 */
11
12#include <sys/cdefs.h>
13#if 0
14#if defined(LIBC_SCCS) && !defined(lint)
15__RCSID("$NetBSD: twalk.c,v 1.4 2012/03/20 16:38:45 matt Exp $");
16#endif /* LIBC_SCCS and not lint */
17#endif
18#define _SEARCH_PRIVATE
19#include <search.h>
20#include <stdlib.h>
21
22typedef void (*cmp_fn_t)(const posix_tnode *, VISIT, int);
23
24/* Walk the nodes of a tree */
25static void
26trecurse(const posix_tnode *root, cmp_fn_t action, int level)
27{
28
29	if (root->llink == NULL && root->rlink == NULL)
30		(*action)(root, leaf, level);
31	else {
32		(*action)(root, preorder, level);
33		if (root->llink != NULL)
34			trecurse(root->llink, action, level + 1);
35		(*action)(root, postorder, level);
36		if (root->rlink != NULL)
37			trecurse(root->rlink, action, level + 1);
38		(*action)(root, endorder, level);
39	}
40}
41
42/* Walk the nodes of a tree */
43void
44twalk(const posix_tnode *vroot, cmp_fn_t action)
45{
46	if (vroot != NULL && action != NULL)
47		trecurse(vroot, action, 0);
48}
49