lib/libc/citrus/citrus_db_hash.c

   1 /* $FreeBSD: head/lib/libc/iconv/citrus_db_hash.c 219019 2011-02-25 00:04:39Z gabor $ */
   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 }