1 /* $NetBSD: longjmp.c,v 1.3 2011/04/30 23:41:12 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 <stddef.h> 39 40 #define __LIBC12_SOURCE__ 41 #include <setjmp.h> 42 #include <compat/include/setjmp.h> 43 44 struct __jmp_buf_regs_t { 45 __greg_t g4; 46 __greg_t g7; 47 __greg_t save_mask; 48 }; 49 50 /* 51 * setjmp.S uses hard coded offsets into the jump_buf, 52 * make sure any changes cause a compile failure here 53 */ 54 __CTASSERT(56 == offsetof(struct __jmp_buf_regs_t,save_mask) + 55 sizeof(struct sigcontext)); 56 __CTASSERT(sizeof(sigjmp_buf) >= sizeof(struct __jmp_buf_regs_t) + 57 sizeof(struct sigcontext)); 58 59 /* 60 * Use setcontext to reload the stack pointer, program counter <pc,npc>, and 61 * set the return value in %o0. The %i and %l registers will be reloaded 62 * from the place to which %sp points. 63 */ 64 void 65 __longjmp14(jmp_buf env, int val) 66 { 67 struct sigcontext *sc = (void *)env; 68 struct __jmp_buf_regs_t *r = (void*)&sc[1]; 69 ucontext_t uc; 70 71 /* Ensure non-zero SP */ 72 if (sc->sc_sp == 0) 73 goto err; 74 75 /* Initialise the context */ 76 memset(&uc, 0, sizeof(uc)); 77 78 /* 79 * Set _UC_{SET,CLR}STACK according to SS_ONSTACK. 80 * 81 * Restore the signal mask with sigprocmask() instead of _UC_SIGMASK, 82 * since libpthread may want to interpose on signal handling. 83 */ 84 uc.uc_flags = _UC_CPU | (sc->sc_onstack ? _UC_SETSTACK : _UC_CLRSTACK); 85 86 sigprocmask(SIG_SETMASK, &sc->sc_mask, NULL); 87 88 /* Extract PSR, PC, NPC and SP from jmp_buf */ 89 uc.uc_mcontext.__gregs[_REG_PSR] = sc->sc_psr; 90 uc.uc_mcontext.__gregs[_REG_PC] = sc->sc_pc; 91 uc.uc_mcontext.__gregs[_REG_nPC] = sc->sc_pc+4; 92 uc.uc_mcontext.__gregs[_REG_O6] = sc->sc_sp; 93 uc.uc_mcontext.__gregs[_REG_G2] = sc->sc_g1; 94 uc.uc_mcontext.__gregs[_REG_G3] = sc->sc_npc; 95 uc.uc_mcontext.__gregs[_REG_G4] = r->g4; 96 uc.uc_mcontext.__gregs[_REG_G7] = r->g7; 97 98 /* Set the return value; make sure it's non-zero */ 99 uc.uc_mcontext.__gregs[_REG_O0] = (val != 0 ? val : 1); 100 101 setcontext(&uc); 102 103 err: 104 longjmperror(); 105 abort(); 106 /* NOTREACHED */ 107 } 108