1 /* $NetBSD: twalk.c,v 1.4 2012/03/20 16:38:45 matt Exp $ */
4 * Tree search generalized from Knuth (6.2.2) Algorithm T just like
5 * the AT&T man page says.
7 * The node_t structure is for internal use only, lint doesn't grok it.
9 * Written by reading the System V Interface Definition, not the code.
11 * Totally public domain.
14 #include <sys/cdefs.h>
16 #if defined(LIBC_SCCS) && !defined(lint)
17 __RCSID("$NetBSD: twalk.c,v 1.4 2012/03/20 16:38:45 matt Exp $");
18 #endif /* LIBC_SCCS and not lint */
20 __FBSDID("$FreeBSD$");
22 #define _SEARCH_PRIVATE
26 typedef void (*cmp_fn_t)(const void *, VISIT, int);
28 /* Walk the nodes of a tree */
30 trecurse(const node_t *root, /* Root of the tree to be walked */
31 cmp_fn_t action, int level)
34 if (root->llink == NULL && root->rlink == NULL)
35 (*action)(root, leaf, level);
37 (*action)(root, preorder, level);
38 if (root->llink != NULL)
39 trecurse(root->llink, action, level + 1);
40 (*action)(root, postorder, level);
41 if (root->rlink != NULL)
42 trecurse(root->rlink, action, level + 1);
43 (*action)(root, endorder, level);
47 /* Walk the nodes of a tree */
49 twalk(const void *vroot, cmp_fn_t action) /* Root of the tree to be walked */
51 if (vroot != NULL && action != NULL)
52 trecurse(vroot, action, 0);