xref: /netbsd-src/lib/libc/arch/sparc64/gen/longjmp.c (revision 1b9578b8c2c1f848eeb16dabbfd7d1f0d9fdefbd)
1 /*	$NetBSD: longjmp.c,v 1.6 2011/04/30 23:39:08 martin 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  *
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 "namespace.h"
33 #include <sys/types.h>
34 #include <ucontext.h>
35 #include <signal.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <stdio.h>
39 #include <stddef.h>
40 
41 #define __LIBC12_SOURCE__
42 #include <setjmp.h>
43 #include <compat/include/setjmp.h>
44 
45 typedef struct {
46 	__greg_t	g3;
47 	__greg_t	g6;
48 	__greg_t	g7;
49 	__greg_t	dummy;
50 	__greg_t	save_mask;
51 } __jmp_buf_regs_t;
52 
53 /*
54  * setjmp.S uses hard coded offsets into the jump_buf,
55  * make sure any changes cause a compile failure here
56  */
57 __CTASSERT(0x68 == offsetof(__jmp_buf_regs_t,save_mask)+
58 	sizeof(struct sigcontext));
59 __CTASSERT(sizeof(sigjmp_buf) >= sizeof(__jmp_buf_regs_t) +
60 	sizeof(struct sigcontext));
61 
62 void
63 __longjmp14(jmp_buf env, int val)
64 {
65 	struct sigcontext *sc = (void *)env;
66 	__jmp_buf_regs_t *r = (void *)&sc[1];
67 	ucontext_t uc;
68 
69 	/* Ensure non-zero SP */
70 	if (sc->sc_sp == 0)
71 		goto err;
72 
73 	/*
74 	 * Set _UC_CPU. No FPU data saved, so we can't restore
75 	 * that. Set _UC_{SET,CLR}STACK according to SS_ONSTACK
76 	 */
77 	memset(&uc, 0, sizeof(uc));
78 	uc.uc_flags = _UC_CPU | (sc->sc_onstack ? _UC_SETSTACK : _UC_CLRSTACK);
79 
80 	/*
81 	 * Set the signal mask - this is a weak symbol, so don't use
82 	 * _UC_SIGMASK in the mcontext, libpthread might override sigprocmask.
83 	 */
84 	sigprocmask(SIG_SETMASK, &sc->sc_mask, NULL);
85 
86 	/* Fill other registers */
87 	uc.uc_mcontext.__gregs[_REG_CCR] = sc->sc_tstate;
88 	uc.uc_mcontext.__gregs[_REG_PC] = sc->sc_pc;
89 	uc.uc_mcontext.__gregs[_REG_nPC] = sc->sc_pc+4;
90 	uc.uc_mcontext.__gregs[_REG_G1] = sc->sc_g1;
91 	uc.uc_mcontext.__gregs[_REG_G2] = sc->sc_o0;
92 	uc.uc_mcontext.__gregs[_REG_G3] = r->g3;
93 	uc.uc_mcontext.__gregs[_REG_G4] = 0;
94 	uc.uc_mcontext.__gregs[_REG_G5] = 0;
95 	uc.uc_mcontext.__gregs[_REG_G6] = r->g6;
96 	uc.uc_mcontext.__gregs[_REG_G7] = r->g7;
97 	uc.uc_mcontext.__gregs[_REG_O6] = sc->sc_sp;
98 
99 
100 	/* Make return value non-zero */
101 	if (val == 0)
102 		val = 1;
103 
104 	/* Save return value in context */
105 	uc.uc_mcontext.__gregs[_REG_O0] = val;
106 
107 	setcontext(&uc);
108 
109  err:
110 	longjmperror();
111 	abort();
112 	/* NOTREACHED */
113 }
114