xref: /freebsd/lib/libc/iconv/citrus_db_hash.c (revision 389e4940069316fe667ffa263fa7d6390d0a960f)
1 /* $FreeBSD$ */
2 /* $NetBSD: citrus_db_hash.c,v 1.5 2008/02/09 14:56:20 junyoung Exp $ */
3 
4 /*-
5  * SPDX-License-Identifier: BSD-2-Clause
6  *
7  * Copyright (c)2003 Citrus Project,
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #include <sys/types.h>
34 
35 #include <assert.h>
36 #include <stdio.h>
37 #include <string.h>
38 
39 #include "citrus_namespace.h"
40 #include "citrus_types.h"
41 #include "citrus_bcs.h"
42 #include "citrus_region.h"
43 #include "citrus_db_hash.h"
44 
45 uint32_t
46 _citrus_db_hash_std(struct _region *r)
47 {
48 	const uint8_t *p;
49 	uint32_t hash, tmp;
50 	size_t i;
51 
52 	hash = 0;
53 	p = _region_head(r);
54 
55 	for (i = _region_size(r); i > 0; i--) {
56 		hash <<= 4;
57 		hash += _bcs_tolower(*p);
58 		tmp = hash & 0xF0000000;
59 		if (tmp != 0) {
60 			hash ^= tmp;
61 			hash ^= tmp >> 24;
62 		}
63 		p++;
64 	}
65 	return (hash);
66 }
67