1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22/*
23 * Copyright (c) 1999 by Sun Microsystems, Inc.
24 * All rights reserved.
25 */
26
27#ifndef	_ICONV_TM_HASH_H
28#define	_ICONV_TM_HASH_H
29
30#pragma ident	"%Z%%M%	%I%	%E% SMI"
31
32
33#ifdef	__cplusplus
34extern "C" {
35#endif
36
37
38
39static itm_size_t	hash(const char *, itm_size_t, itm_size_t);
40static itm_num_t	hash_dense_encoding(const unsigned char *, itm_size_t,
41				    const unsigned char *,
42				    const unsigned char *);
43
44
45static itm_size_t
46hash(const char *ptr, itm_size_t size, itm_size_t hash_size)
47{
48	itm_size_t	value;
49
50	value = *(ptr++);
51	--size;
52	for (; 0 < size; --size) {
53		value *= 27239;
54		value += *(ptr++);
55	}
56	return (value % hash_size);
57}
58
59static itm_num_t
60hash_dense_encoding(
61	const unsigned char	*byte_seq,
62	itm_size_t		length,
63	const unsigned char	*byte_seq_min,
64	const unsigned char	*byte_seq_max)
65{
66	long		i;
67	itm_num_t	num;
68
69	num = (*byte_seq - *byte_seq_min);
70	byte_seq_min++;
71	byte_seq_max++;
72	for (i = 1, byte_seq++; i < length;
73	    i++, byte_seq++, byte_seq_min++, byte_seq_max++) {
74		if ((*byte_seq < *byte_seq_min) ||
75		    (*byte_seq_max < *byte_seq)) {
76			return (-1);
77		}
78		num *= (*byte_seq_max - *byte_seq_min + 1);
79		num += (*byte_seq - *byte_seq_min);
80	}
81	return (num);
82}
83
84#ifdef	__cplusplus
85}
86#endif
87
88#endif /* !_ICONV_TM_HASH_H */
89