pthread_specific.c revision 1.23 
1/*	$NetBSD: pthread_specific.c,v 1.23 2012/09/12 14:55:48 matt Exp $	*/
2
3/*-
4 * Copyright (c) 2001, 2007 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Nathan J. Williams.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33__RCSID("$NetBSD: pthread_specific.c,v 1.23 2012/09/12 14:55:48 matt Exp $");
34
35/* Functions and structures dealing with thread-specific data */
36
37#include "pthread.h"
38#include "pthread_int.h"
39
40#include <string.h>
41#include <sys/lwpctl.h>
42
43#include "../libc/include/extern.h" /* for _sys_setcontext() */
44
45int	pthread_setcontext(const ucontext_t *);
46
47__strong_alias(__libc_thr_setspecific,pthread_setspecific)
48__strong_alias(__libc_thr_getspecific,pthread_getspecific)
49__strong_alias(__libc_thr_curcpu,pthread_curcpu_np)
50
51__strong_alias(setcontext,pthread_setcontext)
52
53int
54pthread_setspecific(pthread_key_t key, const void *value)
55{
56	pthread_t self;
57
58	self = pthread__self();
59	/*
60	 * We can't win here on constness. Having been given a
61	 * "const void *", we can only assign it to other const void *,
62	 * and return it from functions that are const void *, without
63	 * generating a warning.
64	 */
65	/*LINTED const cast*/
66	self->pt_specific[key] = (void *) value;
67	self->pt_havespecific = 1;
68
69	return 0;
70}
71
72void *
73pthread_getspecific(pthread_key_t key)
74{
75
76	return pthread__self()->pt_specific[key];
77}
78
79unsigned int
80pthread_curcpu_np(void)
81{
82
83	return pthread__self()->pt_lwpctl->lc_curcpu;
84}
85
86/*
87 * Override setcontext so that pthread private pointer is preserved
88 */
89int
90pthread_setcontext(const ucontext_t *ucp)
91{
92#ifdef _UC_TLSBASE
93	ucontext_t uc;
94	/*
95	 * Only copy and clear _UC_TLSBASE if it is set.
96	 */
97	if (ucp->uc_flags & _UC_TLSBASE) {
98		uc = *ucp;
99		uc.uc_flags &= ~_UC_TLSBASE;
100		ucp = &uc;
101	}
102#endif /* _UC_TLSBASE */
103	return _sys_setcontext(ucp);
104}
105