1/* $NetBSD: longjmp.c,v 1.5 2024/02/20 00:09:31 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 * 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 <stddef.h> 39 40#define __LIBC12_SOURCE__ 41#include <setjmp.h> 42#include <compat/include/setjmp.h> 43 44#include "assym.h" 45#include "sparc_longjmp.h" 46 47/* 48 * check that offsets in the above structures match their usage in the 49 * setjmp() side of this setup. a jmp_buf is the 12-word contents of 50 * the sigcontext structure, plus 2 more words for g4 and g7. 51 */ 52__CTASSERT(_SIZEOF_SC + _JB_G4 == offsetof(struct __jmp_buf,regs.g4)); 53__CTASSERT(_SIZEOF_SC + _JB_G7 == offsetof(struct __jmp_buf,regs.g7)); 54__CTASSERT(sizeof(jmp_buf) >= sizeof(struct __jmp_buf)); 55 56/* 57 * Use setcontext to reload the stack pointer, program counter <pc,npc>, and 58 * set the return value in %o0. The %i and %l registers will be reloaded 59 * from the place to which %sp points. 60 */ 61void 62__longjmp14(jmp_buf env, int val) 63{ 64 struct __jmp_buf *context = (void *)env; 65 struct sigcontext *sc = &context->sc; 66 struct __jmp_buf_regs_t *r = &context->regs; 67 ucontext_t uc; 68 69 /* Ensure non-zero SP */ 70 if (sc->sc_sp == 0) 71 goto err; 72 73 /* Initialise the context */ 74 memset(&uc, 0, sizeof(uc)); 75 76 /* 77 * Set _UC_{SET,CLR}STACK according to SS_ONSTACK. 78 * 79 * Restore the signal mask with sigprocmask() instead of _UC_SIGMASK, 80 * since libpthread may want to interpose on signal handling. 81 */ 82 uc.uc_flags = _UC_CPU | (sc->sc_onstack ? _UC_SETSTACK : _UC_CLRSTACK); 83 84 sigprocmask(SIG_SETMASK, &sc->sc_mask, NULL); 85 86 /* Extract PSR, PC, NPC and SP from jmp_buf */ 87 uc.uc_mcontext.__gregs[_REG_PSR] = sc->sc_psr; 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_O6] = sc->sc_sp; 91 uc.uc_mcontext.__gregs[_REG_G2] = sc->sc_g1; 92 uc.uc_mcontext.__gregs[_REG_G3] = sc->sc_npc; 93 uc.uc_mcontext.__gregs[_REG_G4] = r->g4; 94 uc.uc_mcontext.__gregs[_REG_G7] = r->g7; 95 96 /* Set the return value; make sure it's non-zero */ 97 uc.uc_mcontext.__gregs[_REG_O0] = (val != 0 ? val : 1); 98 99 setcontext(&uc); 100 101err: 102 longjmperror(); 103 abort(); 104 /* NOTREACHED */ 105} 106