swapcontext.c revision 277317 
1/*
2 * Copyright (c) 2001 Daniel M. Eischen <deischen@freebsd.org>
3 * Copyright (c) 2014 The FreeBSD Foundation.
4 * All rights reserved.
5 *
6 * Portions of this software were developed by Konstantin Belousov
7 * under sponsorship from the FreeBSD Foundation.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Neither the name of the author nor the names of its contributors
15 *    may be used to endorse or promote products derived from this software
16 *    without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31#include <sys/cdefs.h>
32__FBSDID("$FreeBSD: stable/10/lib/libc/sys/swapcontext.c 277317 2015-01-18 11:54:20Z kib $");
33
34#include <sys/param.h>
35#include <sys/signal.h>
36#include <sys/ucontext.h>
37#include <errno.h>
38#include <stddef.h>
39#include "libc_private.h"
40
41__weak_reference(__sys_swapcontext, __swapcontext);
42__sym_compat(swapcontext, __impl_swapcontext, FBSD_1.0);
43__weak_reference(swapcontext, __impl_swapcontext);
44__sym_default(swapcontext, swapcontext, FBSD_1.2);
45
46#pragma weak swapcontext
47int
48swapcontext(ucontext_t *oucp, const ucontext_t *ucp)
49{
50
51	return (((int (*)(ucontext_t *, const ucontext_t *))
52	    __libc_interposing[INTERPOS_swapcontext])(oucp, ucp));
53}
54