1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate * CDDL HEADER START
3*0Sstevel@tonic-gate *
4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance
7*0Sstevel@tonic-gate * with the License.
8*0Sstevel@tonic-gate *
9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate * and limitations under the License.
13*0Sstevel@tonic-gate *
14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate *
20*0Sstevel@tonic-gate * CDDL HEADER END
21*0Sstevel@tonic-gate */
22*0Sstevel@tonic-gate /* Copyright (c) 1984 AT&T */
23*0Sstevel@tonic-gate /* All Rights Reserved */
24*0Sstevel@tonic-gate
25*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" /* from S5R2 1.2 */
26*0Sstevel@tonic-gate
27*0Sstevel@tonic-gate /*LINTLIBRARY*/
28*0Sstevel@tonic-gate /*
29*0Sstevel@tonic-gate * Tree search algorithm, generalized from Knuth (6.2.2) Algorithm T.
30*0Sstevel@tonic-gate *
31*0Sstevel@tonic-gate * The NODE * arguments are declared in the lint files as char *,
32*0Sstevel@tonic-gate * because the definition of NODE isn't available to the user.
33*0Sstevel@tonic-gate */
34*0Sstevel@tonic-gate
35*0Sstevel@tonic-gate #include <search.h>
36*0Sstevel@tonic-gate typedef char *POINTER;
37*0Sstevel@tonic-gate typedef struct node { POINTER key; struct node *llink, *rlink; } NODE;
38*0Sstevel@tonic-gate
39*0Sstevel@tonic-gate #define NULL 0
40*0Sstevel@tonic-gate
41*0Sstevel@tonic-gate
42*0Sstevel@tonic-gate /* tfind - find a node, or return 0 */
43*0Sstevel@tonic-gate NODE *
tfind(key,rootp,compar)44*0Sstevel@tonic-gate tfind(key, rootp, compar)
45*0Sstevel@tonic-gate POINTER key; /* Key to be located */
46*0Sstevel@tonic-gate register NODE **rootp; /* Address of the root of the tree */
47*0Sstevel@tonic-gate int (*compar)(); /* Comparison function */
48*0Sstevel@tonic-gate {
49*0Sstevel@tonic-gate if (rootp == NULL)
50*0Sstevel@tonic-gate return (NULL);
51*0Sstevel@tonic-gate while (*rootp != NULL) { /* T1: */
52*0Sstevel@tonic-gate int r = (*compar)(key, (*rootp)->key); /* T2: */
53*0Sstevel@tonic-gate if (r == 0)
54*0Sstevel@tonic-gate return (*rootp); /* Key found */
55*0Sstevel@tonic-gate rootp = (r < 0) ?
56*0Sstevel@tonic-gate &(*rootp)->llink : /* T3: Take left branch */
57*0Sstevel@tonic-gate &(*rootp)->rlink; /* T4: Take right branch */
58*0Sstevel@tonic-gate }
59*0Sstevel@tonic-gate return (NODE *)(NULL);
60*0Sstevel@tonic-gate }
61