1/*	$NetBSD: longjmp.c,v 1.6 2016/01/24 16:01:43 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 and Matt Thomas.
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
39#include <machine/regnum.h>
40
41#define __LIBC12_SOURCE__
42#include <setjmp.h>
43#include <compat/include/setjmp.h>
44
45void
46__longjmp14(jmp_buf env, int val)
47{
48	struct sigcontext *sc = (void *)env;
49	ucontext_t uc;
50
51	/* Ensure non-zero SP and sigcontext magic number is present */
52	if (sc->sc_regs[_R_SP] == 0 || sc->sc_regs[_R_ZERO] != (__register_t)0xACEDBADEU)
53		goto err;
54
55	/* Ensure non-zero return value */
56	if (val == 0)
57		val = 1;
58
59	/*
60	 * Set _UC_{SET,CLR}STACK according to SS_ONSTACK.
61	 *
62	 * Restore the signal mask with sigprocmask() instead of _UC_SIGMASK,
63	 * since libpthread may want to interpose on signal handling.
64	 */
65	uc.uc_flags = _UC_CPU | (sc->sc_onstack ? _UC_SETSTACK : _UC_CLRSTACK);
66
67	sigprocmask(SIG_SETMASK, &sc->sc_mask, NULL);
68
69	/* Clear uc_link */
70	uc.uc_link = 0;
71
72	/* Save return value in context */
73	uc.uc_mcontext.__gregs[_REG_V0] = val;
74
75	/* Copy saved registers */
76	uc.uc_mcontext.__gregs[_REG_S0] = sc->sc_regs[_R_S0];
77	uc.uc_mcontext.__gregs[_REG_S1] = sc->sc_regs[_R_S1];
78	uc.uc_mcontext.__gregs[_REG_S2] = sc->sc_regs[_R_S2];
79	uc.uc_mcontext.__gregs[_REG_S3] = sc->sc_regs[_R_S3];
80	uc.uc_mcontext.__gregs[_REG_S4] = sc->sc_regs[_R_S4];
81	uc.uc_mcontext.__gregs[_REG_S5] = sc->sc_regs[_R_S5];
82	uc.uc_mcontext.__gregs[_REG_S6] = sc->sc_regs[_R_S6];
83	uc.uc_mcontext.__gregs[_REG_S7] = sc->sc_regs[_R_S7];
84	uc.uc_mcontext.__gregs[_REG_S8] = sc->sc_regs[_R_S8];
85#if defined(__mips_n32) || defined(__mips_n64)
86	uc.uc_mcontext.__gregs[_REG_GP] = sc->sc_regs[_R_GP];
87#endif
88	uc.uc_mcontext.__gregs[_REG_SP] = sc->sc_regs[_R_SP];
89	uc.uc_mcontext.__gregs[_REG_RA] = sc->sc_regs[_R_RA];
90	uc.uc_mcontext.__gregs[_REG_EPC] = sc->sc_pc;
91
92	/* Copy FP state */
93	if (sc->sc_fpused) {
94		/* FP saved regs are $f20 .. $f31 */
95		memcpy(&uc.uc_mcontext.__fpregs.__fp_r.__fp_regs[20],
96		    &sc->sc_fpregs[20], 32 - 20);
97		uc.uc_mcontext.__fpregs.__fp_csr =
98		    sc->sc_fpregs[_R_FSR - _FPBASE];
99		/* XXX sc_fp_control */
100		uc.uc_flags |= _UC_FPU;
101	}
102
103	setcontext(&uc);
104 err:
105	longjmperror();
106	abort();
107	/* NOTREACHED */
108}
109