1/*	$NetBSD: tfind.c,v 1.2 1999/09/16 11:45:37 lukem 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: tfind.c,v 1.2 1999/09/16 11:45:37 lukem Exp $");
16#endif /* LIBC_SCCS and not lint */
17#endif
18__FBSDID("$FreeBSD: stable/11/lib/libc/stdlib/tfind.c 308090 2016-10-29 14:41:22Z ed $");
19
20#define _SEARCH_PRIVATE
21#include <stdlib.h>
22#include <search.h>
23
24/*
25 * find a node, or return 0
26 *
27 * vkey   - key to be found
28 * vrootp - address of the tree root
29 */
30posix_tnode *
31tfind(const void *vkey, posix_tnode * const *rootp,
32    int (*compar)(const void *, const void *))
33{
34
35	if (rootp == NULL)
36		return NULL;
37
38	while (*rootp != NULL) {		/* T1: */
39		int r;
40
41		if ((r = (*compar)(vkey, (*rootp)->key)) == 0)	/* T2: */
42			return *rootp;		/* key found */
43		rootp = (r < 0) ?
44		    &(*rootp)->llink :		/* T3: follow left branch */
45		    &(*rootp)->rlink;		/* T4: follow right branch */
46	}
47	return NULL;
48}
49