xref: /netbsd-src/lib/libc/arch/m68k/gen/longjmp.c (revision fad4c9f71477ae11cea2ee75ec82151ac770a534)
1 /*	$NetBSD: longjmp.c,v 1.1 2006/03/09 16:20:27 christos 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 typedef struct {
51 	__greg_t	__data[6];
52 	__greg_t	__addr[4];
53 } __jmp_buf_regs_t;
54 
55 void
56 __longjmp14(jmp_buf env, int val)
57 {
58 	struct sigcontext *sc = (void *)env;
59 	__jmp_buf_regs_t *r = (void *)&sc[1];
60 	ucontext_t uc;
61 
62 	/* Ensure non-zero SP */
63 	if (sc->sc_sp == 0)
64 		goto err;
65 
66 	/* Make return value non-zero */
67 	if (val == 0)
68 		val = 1;
69 
70 	/* Save return value in context */
71 	uc.uc_mcontext.__gregs[_REG_D0] = val;
72 
73 	/*
74 	 * Set _UC_SIGMASK, _UC_CPU and _UC_M68K_UC_USER
75 	 * Set _UC_{SET,CLR}STACK according to SS_ONSTACK
76 	 */
77 	uc.uc_flags = _UC_SIGMASK | _UC_CPU | _UC_M68K_UC_USER |
78 		(sc->sc_onstack ? _UC_SETSTACK : _UC_CLRSTACK);
79 
80 	/* Clear uc_link */
81 	uc.uc_link = 0;
82 
83 	/* Copy signal mask */
84 	uc.uc_sigmask = sc->sc_mask;
85 
86 	/* Copy SP/PC/PS/FP */
87 	uc.uc_mcontext.__gregs[_REG_A7] = sc->sc_sp;
88 	uc.uc_mcontext.__gregs[_REG_PC] = sc->sc_pc;
89 	uc.uc_mcontext.__gregs[_REG_PS] = sc->sc_ps;
90 	uc.uc_mcontext.__gregs[_REG_A6] = sc->sc_fp;
91 
92 	/* Copy remaining non-scratch regs. */
93 	memcpy(&uc.uc_mcontext.__gregs[_REG_D2],
94 	    &r->__data, sizeof(r->__data));
95 	memcpy(&uc.uc_mcontext.__gregs[_REG_A2],
96 	    &r->__addr, sizeof(r->__addr));
97 
98 	setcontext(&uc);
99  err:
100 	longjmperror();
101 	abort();
102 	/* NOTREACHED */
103 }
104