xref: /freebsd/lib/libc/iconv/citrus_db_hash.c (revision ca987d4641cdcd7f27e153db17c5bf064934faf5)
1 /* $FreeBSD$ */
2 /* $NetBSD: citrus_db_hash.c,v 1.5 2008/02/09 14:56:20 junyoung Exp $ */
3 
4 /*-
5  * Copyright (c)2003 Citrus Project,
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 #include <sys/types.h>
32 
33 #include <assert.h>
34 #include <stdio.h>
35 #include <string.h>
36 
37 #include "citrus_namespace.h"
38 #include "citrus_types.h"
39 #include "citrus_bcs.h"
40 #include "citrus_region.h"
41 #include "citrus_db_hash.h"
42 
43 uint32_t
44 _citrus_db_hash_std(struct _region *r)
45 {
46 	const uint8_t *p;
47 	uint32_t hash, tmp;
48 	size_t i;
49 
50 	hash = 0;
51 	p = _region_head(r);
52 
53 	for (i = _region_size(r); i > 0; i--) {
54 		hash <<= 4;
55 		hash += _bcs_tolower(*p);
56 		tmp = hash & 0xF0000000;
57 		if (tmp != 0) {
58 			hash ^= tmp;
59 			hash ^= tmp >> 24;
60 		}
61 		p++;
62 	}
63 	return (hash);
64 }
65