xref: /illumos-gate/usr/src/lib/libc/amd64/gen/siglongjmp.c (revision 0250c53ad267726f2438e3c6556199a0bbf588a2)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * Copyright 2023 Oxide Computer Company
29  */
30 
31 #include "lint.h"
32 #include <sys/types.h>
33 #include <sys/ucontext.h>
34 #include <setjmp.h>
35 #include <ucontext.h>
36 #include <strings.h>
37 #include <upanic.h>
38 #include "sigjmp_struct.h"
39 #include "libc.h"
40 
41 #pragma weak _siglongjmp = siglongjmp
42 
43 void
44 siglongjmp(sigjmp_buf env, int val)
45 {
46 	const char *msg = "siglongjmp(): setcontext() returned";
47 	ucontext_t *ucp = SIGJMP2UCONTEXT(env);
48 
49 	if (val)
50 		ucp->uc_mcontext.gregs[REG_R0] = val;
51 	else
52 		ucp->uc_mcontext.gregs[REG_R0] = 1;
53 
54 	/*
55 	 * While unlikely, it is possible that setcontext() may fail for some
56 	 * reason. If that happens, we will kill the process.
57 	 */
58 	(void) setcontext(ucp);
59 	upanic(msg, strlen(msg) + 1);
60 }
61