xref: /titanic_51/usr/src/contrib/ast/src/lib/libast/aso/asolock.c (revision b4dd7d09880f14016feece03929a224eca1cf39a)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1985-2011 AT&T Intellectual Property          *
5 *                      and is licensed under the                       *
6 *                 Eclipse Public License, Version 1.0                  *
7 *                    by AT&T Intellectual Property                     *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *          http://www.eclipse.org/org/documents/epl-v10.html           *
11 *         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
12 *                                                                      *
13 *              Information and Software Systems Research               *
14 *                            AT&T Research                             *
15 *                           Florham Park NJ                            *
16 *                                                                      *
17 *                 Glenn Fowler <gsf@research.att.com>                  *
18 *                  David Korn <dgk@research.att.com>                   *
19 *                   Phong Vo <kpv@research.att.com>                    *
20 *                                                                      *
21 ***********************************************************************/
22 #pragma prototyped
23 
24 #include "asohdr.h"
25 
26 #if defined(_UWIN) && defined(_BLD_ast)
27 
28 NoN(asolock)
29 
30 #else
31 
32 int
33 asolock(unsigned int volatile* lock, unsigned int key, int type)
34 {
35 	unsigned int	k;
36 
37 	if (key)
38 		switch (type)
39 		{
40 		case ASO_UNLOCK:
41 			return *lock == 0 ? 0 : asocasint(lock, key, 0) == key ? 0 : -1;
42 		case ASO_TRYLOCK:
43 			return *lock == key ? 0 : asocasint(lock, 0, key) == 0 ? 0 : -1;
44 		case ASO_LOCK:
45 			if (*lock == key)
46 				return 0;
47 			/*FALLTHROUGH*/
48 		case ASO_SPINLOCK:
49 			for (k = 0; asocasint(lock, 0, key) != 0; ASOLOOP(k));
50 			return 0;
51 		}
52 	return -1;
53 }
54 
55 #endif
56