xref: /netbsd-src/external/bsd/elftoolchain/dist/libelf/elf_hash.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: elf_hash.c,v 1.3 2016/02/20 02:43:42 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2006,2008 Joseph Koshy
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <libelf.h>
30 
31 #include "_libelf.h"
32 
33 __RCSID("$NetBSD: elf_hash.c,v 1.3 2016/02/20 02:43:42 christos Exp $");
34 ELFTC_VCSID("Id: elf_hash.c 3174 2015-03-27 17:13:41Z emaste ");
35 
36 /*
37  * This elf_hash function is defined by the System V ABI.
38  */
39 
40 unsigned long
41 elf_hash(const void *name)
42 {
43 	unsigned long h, t;
44 	const unsigned char *s;
45 
46 	s = (const unsigned char *) name;
47 	h = t = 0;
48 
49 	for (; *s != '\0'; h = h & ~t) {
50 		h = (h << 4) + *s++;
51 		t = h & 0xF0000000UL;
52 		if (t)
53 			h ^= t >> 24;
54 	}
55 
56 	return (h);
57 }
58