xref: /netbsd-src/lib/libc/arch/sparc/gen/longjmp.c (revision d48f14661dda8638fee055ba15d35bdfb29b9fa8)
1 /*	$NetBSD: longjmp.c,v 1.1 2005/10/15 22:11:22 uwe Exp $	*/
2 
3 /*-
4  * Copyright (c) 2003 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Christian Limpach.
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  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include "namespace.h"
40 #include <sys/types.h>
41 #include <ucontext.h>
42 #include <signal.h>
43 #include <stdlib.h>
44 #include <string.h>
45 
46 #define __LIBC12_SOURCE__
47 #include <setjmp.h>
48 #include <compat/include/setjmp.h>
49 
50 /*
51  * Use setcontext to reload the stack pointer, program counter <pc,npc>, and
52  * set the return value in %o0.  The %i and %l registers will be reloaded
53  * from the place to which %sp points.
54  */
55 void
56 __longjmp14(jmp_buf env, int val)
57 {
58 	struct sigcontext *sc = (void *)env;
59 	ucontext_t uc;
60 
61 	/* Ensure non-zero SP */
62 	if (sc->sc_sp == 0)
63 		goto err;
64 
65 	/* Initialise the fields we're going to use */
66 	uc.uc_link = 0;
67 
68 	/*
69 	 * Set _UC_{SET,CLR}STACK according to SS_ONSTACK.
70 	 *
71 	 * Restore the signal mask with sigprocmask() instead of _UC_SIGMASK,
72 	 * since libpthread may want to interpose on signal handling.
73 	 */
74 	uc.uc_flags = _UC_CPU | (sc->sc_onstack ? _UC_SETSTACK : _UC_CLRSTACK);
75 
76 	sigprocmask(SIG_SETMASK, &sc->sc_mask, NULL);
77 
78 	/* Extract PSR, PC, NPC and SP from jmp_buf */
79 	uc.uc_mcontext.__gregs[_REG_PSR] = sc->sc_psr;
80 	uc.uc_mcontext.__gregs[_REG_PC] = sc->sc_pc;
81 	uc.uc_mcontext.__gregs[_REG_nPC] = sc->sc_npc;
82 	uc.uc_mcontext.__gregs[_REG_O6] = sc->sc_sp;
83 
84 	/* Set the return value; make sure it's non-zero */
85 	uc.uc_mcontext.__gregs[_REG_O0] = (val != 0 ? val : 1);
86 
87 	setcontext(&uc);
88 
89 err:
90 	longjmperror();
91 	abort();
92 	/* NOTREACHED */
93 }
94