xref: /freebsd/contrib/elftoolchain/libelf/elf_hash.c (revision 3f05af05ace08ae28892ecfd28b000822a5d7ae0)
1 /*-
2  * Copyright (c) 2006,2008 Joseph Koshy
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 
29 #include <libelf.h>
30 
31 #include "_libelf.h"
32 
33 ELFTC_VCSID("$Id: elf_hash.c 2225 2011-11-26 18:55:54Z jkoshy $");
34 
35 /*
36  * This elf_hash function is defined by the System V ABI.
37  */
38 
39 unsigned long
40 elf_hash(const char *name)
41 {
42 	unsigned long h, t;
43 	const unsigned char *s;
44 
45 	s = (const unsigned char *) name;
46 	h = t = 0;
47 
48 	for (; *s != '\0'; h = h & ~t) {
49 		h = (h << 4) + *s++;
50 		t = h & 0xF0000000UL;
51 		if (t)
52 			h ^= t >> 24;
53 	}
54 
55 	return (h);
56 }
57