xref: /freebsd/lib/libc/iconv/citrus_db_hash.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
1 /* $NetBSD: citrus_db_hash.c,v 1.5 2008/02/09 14:56:20 junyoung Exp $ */
2 
3 /*-
4  * SPDX-License-Identifier: BSD-2-Clause
5  *
6  * Copyright (c)2003 Citrus Project,
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 #include <sys/types.h>
33 
34 #include <assert.h>
35 #include <stdio.h>
36 #include <string.h>
37 
38 #include "citrus_namespace.h"
39 #include "citrus_types.h"
40 #include "citrus_bcs.h"
41 #include "citrus_region.h"
42 #include "citrus_db_hash.h"
43 
44 uint32_t
45 _citrus_db_hash_std(struct _region *r)
46 {
47 	const uint8_t *p;
48 	uint32_t hash, tmp;
49 	size_t i;
50 
51 	hash = 0;
52 	p = _region_head(r);
53 
54 	for (i = _region_size(r); i > 0; i--) {
55 		hash <<= 4;
56 		hash += _bcs_tolower(*p);
57 		tmp = hash & 0xF0000000;
58 		if (tmp != 0) {
59 			hash ^= tmp;
60 			hash ^= tmp >> 24;
61 		}
62 		p++;
63 	}
64 	return (hash);
65 }
66