pthread_specific.c revision 1.24 
1/*	$NetBSD: pthread_specific.c,v 1.24 2012/11/21 19:19:24 christos 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 1.24 2012/11/21 19:19:24 christos 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	return pthread__add_specific(self, key, value);
66}
67
68void *
69pthread_getspecific(pthread_key_t key)
70{
71
72	return pthread__self()->pt_specific[key].pts_value;
73}
74
75unsigned int
76pthread_curcpu_np(void)
77{
78
79	return pthread__self()->pt_lwpctl->lc_curcpu;
80}
81
82/*
83 * Override setcontext so that pthread private pointer is preserved
84 */
85int
86pthread_setcontext(const ucontext_t *ucp)
87{
88#ifdef _UC_TLSBASE
89	ucontext_t uc;
90	/*
91	 * Only copy and clear _UC_TLSBASE if it is set.
92	 */
93	if (ucp->uc_flags & _UC_TLSBASE) {
94		uc = *ucp;
95		uc.uc_flags &= ~_UC_TLSBASE;
96		ucp = &uc;
97	}
98#endif /* _UC_TLSBASE */
99	return _sys_setcontext(ucp);
100}
101