| 1 |
gbeauche |
1.1 |
/* |
| 2 |
|
|
* sigsegv.cpp - SIGSEGV signals support |
| 3 |
|
|
* |
| 4 |
|
|
* Derived from Bruno Haible's work on his SIGSEGV library for clisp |
| 5 |
|
|
* <http://clisp.sourceforge.net/> |
| 6 |
|
|
* |
| 7 |
|
|
* Basilisk II (C) 1997-2001 Christian Bauer |
| 8 |
|
|
* |
| 9 |
|
|
* This program is free software; you can redistribute it and/or modify |
| 10 |
|
|
* it under the terms of the GNU General Public License as published by |
| 11 |
|
|
* the Free Software Foundation; either version 2 of the License, or |
| 12 |
|
|
* (at your option) any later version. |
| 13 |
|
|
* |
| 14 |
|
|
* This program is distributed in the hope that it will be useful, |
| 15 |
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 16 |
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 17 |
|
|
* GNU General Public License for more details. |
| 18 |
|
|
* |
| 19 |
|
|
* You should have received a copy of the GNU General Public License |
| 20 |
|
|
* along with this program; if not, write to the Free Software |
| 21 |
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 22 |
|
|
*/ |
| 23 |
|
|
|
| 24 |
|
|
#ifdef HAVE_UNISTD_H |
| 25 |
|
|
#include <unistd.h> |
| 26 |
|
|
#endif |
| 27 |
|
|
|
| 28 |
|
|
#ifdef HAVE_CONFIG_H |
| 29 |
|
|
#include "config.h" |
| 30 |
|
|
#endif |
| 31 |
|
|
|
| 32 |
|
|
#include <signal.h> |
| 33 |
|
|
#include "sigsegv.h" |
| 34 |
|
|
|
| 35 |
|
|
// Return value type of a signal handler (standard type if not defined) |
| 36 |
|
|
#ifndef RETSIGTYPE |
| 37 |
|
|
#define RETSIGTYPE void |
| 38 |
|
|
#endif |
| 39 |
|
|
|
| 40 |
|
|
// Type of the system signal handler |
| 41 |
|
|
typedef RETSIGTYPE (*signal_handler)(int); |
| 42 |
|
|
|
| 43 |
|
|
// User's SIGSEGV handler |
| 44 |
|
|
static sigsegv_handler_t sigsegv_user_handler = 0; |
| 45 |
|
|
|
| 46 |
|
|
// Actual SIGSEGV handler installer |
| 47 |
|
|
static bool sigsegv_do_install_handler(int sig); |
| 48 |
|
|
|
| 49 |
|
|
|
| 50 |
|
|
/* |
| 51 |
|
|
* OS-dependant SIGSEGV signals support section |
| 52 |
|
|
*/ |
| 53 |
|
|
|
| 54 |
|
|
#if HAVE_SIGINFO_T |
| 55 |
|
|
// Generic extended signal handler |
| 56 |
|
|
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
| 57 |
|
|
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, siginfo_t *sip, void * |
| 58 |
|
|
#define SIGSEGV_FAULT_ADDRESS sip->si_addr |
| 59 |
|
|
#endif |
| 60 |
|
|
|
| 61 |
|
|
#if HAVE_SIGCONTEXT_SUBTERFUGE |
| 62 |
|
|
// Linux kernels prior to 2.4 ? |
| 63 |
|
|
#if defined(__linux__) |
| 64 |
|
|
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
| 65 |
|
|
#if (defined(i386) || defined(__i386__)) |
| 66 |
|
|
#include <asm/sigcontext.h> |
| 67 |
|
|
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, struct sigcontext scs |
| 68 |
|
|
#define SIGSEGV_FAULT_ADDRESS scs.cr2 |
| 69 |
|
|
#define SIGSEGV_FAULT_INSTRUCTION scs.eip |
| 70 |
|
|
#endif |
| 71 |
|
|
#if (defined(sparc) || defined(__sparc__)) |
| 72 |
|
|
#include <asm/sigcontext.h> |
| 73 |
|
|
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext* scp, char* addr |
| 74 |
|
|
#define SIGSEGV_FAULT_ADDRESS addr |
| 75 |
|
|
#endif |
| 76 |
|
|
#if (defined(powerpc) || defined(__powerpc__)) |
| 77 |
|
|
#include <asm/sigcontext.h> |
| 78 |
|
|
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, struct sigcontext* scp |
| 79 |
|
|
#define SIGSEGV_FAULT_ADDRESS scp->regs->dar |
| 80 |
|
|
#define SIGSEGV_FAULT_INSTRUCTION scp->regs->nip |
| 81 |
|
|
#endif |
| 82 |
|
|
#endif |
| 83 |
|
|
|
| 84 |
|
|
// Irix 5 or 6 on MIPS |
| 85 |
|
|
#if (defined(sgi) || defined(__sgi)) && (defined(SYSTYPE_SVR4) || defined(__SYSTYPE_SVR4)) |
| 86 |
|
|
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp |
| 87 |
|
|
#define SIGSEGV_FAULT_ADDRESS scp->sc_badvaddr |
| 88 |
|
|
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
| 89 |
|
|
#endif |
| 90 |
|
|
|
| 91 |
|
|
// OSF/1 on Alpha |
| 92 |
|
|
#if defined(__osf__) |
| 93 |
|
|
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp |
| 94 |
|
|
#define SIGSEGV_FAULT_ADDRESS scp->sc_traparg_a0 |
| 95 |
|
|
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
| 96 |
|
|
#endif |
| 97 |
|
|
|
| 98 |
|
|
// AIX |
| 99 |
|
|
#if defined(_AIX) |
| 100 |
|
|
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp |
| 101 |
|
|
#define SIGSEGV_FAULT_ADDRESS scp->sc_jmpbuf.jmp_context.o_vaddr |
| 102 |
|
|
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
| 103 |
|
|
#endif |
| 104 |
|
|
|
| 105 |
|
|
// NetBSD or FreeBSD |
| 106 |
|
|
#if defined(__NetBSD__) || defined(__FreeBSD__) |
| 107 |
|
|
#if (defined(m68k) || defined(__m68k__)) |
| 108 |
|
|
#include <m68k/frame.h> |
| 109 |
|
|
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp |
| 110 |
|
|
#define SIGSEGV_FAULT_ADDRESS ({ \ |
| 111 |
|
|
struct sigstate { \ |
| 112 |
|
|
int ss_flags; \ |
| 113 |
|
|
struct frame ss_frame; \ |
| 114 |
|
|
}; \ |
| 115 |
|
|
struct sigstate *state = (struct sigstate *)scp->sc_ap; \ |
| 116 |
|
|
char *fault_addr; \ |
| 117 |
|
|
switch (state->ss_frame.f_format) { \ |
| 118 |
|
|
case 7: /* 68040 access error */ \ |
| 119 |
|
|
/* "code" is sometimes unreliable (i.e. contains NULL or a bogus address), reason unknown */ \ |
| 120 |
|
|
fault_addr = state->ss_frame.f_fmt7.f_fa; \ |
| 121 |
|
|
break; \ |
| 122 |
|
|
default: \ |
| 123 |
|
|
fault_addr = (char *)code; \ |
| 124 |
|
|
break; \ |
| 125 |
|
|
} \ |
| 126 |
|
|
fault_addr; \ |
| 127 |
|
|
}) |
| 128 |
|
|
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
| 129 |
|
|
#else |
| 130 |
|
|
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, void *scp, char *addr |
| 131 |
|
|
#define SIGSEGV_FAULT_ADDRESS addr |
| 132 |
|
|
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGBUS) |
| 133 |
|
|
#endif |
| 134 |
|
|
#endif |
| 135 |
|
|
#endif |
| 136 |
|
|
|
| 137 |
|
|
// Fallbacks |
| 138 |
|
|
#ifndef SIGSEGV_FAULT_INSTRUCTION |
| 139 |
|
|
#define SIGSEGV_FAULT_INSTRUCTION SIGSEGV_INVALID_PC |
| 140 |
|
|
#endif |
| 141 |
|
|
|
| 142 |
|
|
|
| 143 |
|
|
/* |
| 144 |
|
|
* SIGSEGV global handler |
| 145 |
|
|
*/ |
| 146 |
|
|
|
| 147 |
|
|
static void sigsegv_handler(SIGSEGV_FAULT_HANDLER_ARGLIST) |
| 148 |
|
|
{ |
| 149 |
|
|
// Call user's handler and reinstall the global handler, if required |
| 150 |
|
|
if (sigsegv_user_handler((sigsegv_address_t)SIGSEGV_FAULT_ADDRESS, (sigsegv_address_t)SIGSEGV_FAULT_INSTRUCTION)) { |
| 151 |
|
|
#if (defined(HAVE_SIGACTION) ? defined(SIGACTION_NEED_REINSTALL) : defined(SIGNAL_NEED_REINSTALL)) |
| 152 |
|
|
sigsegv_do_install_handler(sig); |
| 153 |
|
|
#endif |
| 154 |
|
|
} |
| 155 |
|
|
else { |
| 156 |
|
|
// FAIL: reinstall default handler for "safe" crash |
| 157 |
|
|
#define FAULT_HANDLER(sig) signal(sig, SIG_DFL); |
| 158 |
|
|
SIGSEGV_ALL_SIGNALS |
| 159 |
|
|
#undef FAULT_HANDLER |
| 160 |
|
|
} |
| 161 |
|
|
} |
| 162 |
|
|
|
| 163 |
|
|
|
| 164 |
|
|
/* |
| 165 |
|
|
* SIGSEGV handler initialization |
| 166 |
|
|
*/ |
| 167 |
|
|
|
| 168 |
|
|
#if defined(HAVE_SIGINFO_T) |
| 169 |
|
|
static bool sigsegv_do_install_handler(int sig) |
| 170 |
|
|
{ |
| 171 |
|
|
// Setup SIGSEGV handler to process writes to frame buffer |
| 172 |
|
|
#ifdef HAVE_SIGACTION |
| 173 |
|
|
struct sigaction vosf_sa; |
| 174 |
|
|
sigemptyset(&vosf_sa.sa_mask); |
| 175 |
|
|
vosf_sa.sa_sigaction = sigsegv_handler; |
| 176 |
|
|
vosf_sa.sa_flags = SA_SIGINFO; |
| 177 |
|
|
return (sigaction(sig, &vosf_sa, 0) == 0); |
| 178 |
|
|
#else |
| 179 |
|
|
return (signal(sig, (signal_handler)sigsegv_handler) != SIG_ERR); |
| 180 |
|
|
#endif |
| 181 |
|
|
} |
| 182 |
|
|
#elif defined(HAVE_SIGCONTEXT_SUBTERFUGE) |
| 183 |
|
|
static bool sigsegv_do_install_handler(int sig) |
| 184 |
|
|
{ |
| 185 |
|
|
// Setup SIGSEGV handler to process writes to frame buffer |
| 186 |
|
|
#ifdef HAVE_SIGACTION |
| 187 |
|
|
struct sigaction vosf_sa; |
| 188 |
|
|
sigemptyset(&vosf_sa.sa_mask); |
| 189 |
|
|
vosf_sa.sa_handler = (signal_handler)sigsegv_handler; |
| 190 |
|
|
#if !EMULATED_68K && defined(__NetBSD__) |
| 191 |
|
|
sigaddset(&vosf_sa.sa_mask, SIGALRM); |
| 192 |
|
|
vosf_sa.sa_flags = SA_ONSTACK; |
| 193 |
|
|
#else |
| 194 |
|
|
vosf_sa.sa_flags = 0; |
| 195 |
|
|
#endif |
| 196 |
|
|
return (sigaction(sig, &vosf_sa, 0) == 0); |
| 197 |
|
|
#else |
| 198 |
|
|
return (signal(sig, (signal_handler)sigsegv_handler) != SIG_ERR); |
| 199 |
|
|
#endif |
| 200 |
|
|
} |
| 201 |
|
|
#endif |
| 202 |
|
|
|
| 203 |
|
|
bool sigsegv_install_handler(sigsegv_handler_t handler) |
| 204 |
|
|
{ |
| 205 |
|
|
#if defined(HAVE_SIGINFO_T) || defined(HAVE_SIGCONTEXT_SUBTERFUGE) |
| 206 |
|
|
sigsegv_user_handler = handler; |
| 207 |
|
|
bool success = true; |
| 208 |
|
|
#define FAULT_HANDLER(sig) success = success && sigsegv_do_install_handler(sig); |
| 209 |
|
|
SIGSEGV_ALL_SIGNALS |
| 210 |
|
|
#undef FAULT_HANDLER |
| 211 |
|
|
return success; |
| 212 |
|
|
#else |
| 213 |
|
|
// FAIL: no siginfo_t nor sigcontext subterfuge is available |
| 214 |
|
|
return false; |
| 215 |
|
|
#endif |
| 216 |
|
|
} |
| 217 |
|
|
|
| 218 |
|
|
|
| 219 |
|
|
/* |
| 220 |
|
|
* SIGSEGV handler deinitialization |
| 221 |
|
|
*/ |
| 222 |
|
|
|
| 223 |
|
|
void sigsegv_deinstall_handler(void) |
| 224 |
|
|
{ |
| 225 |
|
|
sigsegv_user_handler = 0; |
| 226 |
|
|
#define FAULT_HANDLER(sig) signal(sig, SIG_DFL); |
| 227 |
|
|
SIGSEGV_ALL_SIGNALS |
| 228 |
|
|
#undef FAULT_HANDLER |
| 229 |
|
|
} |
| 230 |
|
|
|
| 231 |
|
|
/* |
| 232 |
|
|
* Test program used for configure/test |
| 233 |
|
|
*/ |
| 234 |
|
|
|
| 235 |
|
|
#ifdef CONFIGURE_TEST |
| 236 |
|
|
#include <stdio.h> |
| 237 |
|
|
#include <stdlib.h> |
| 238 |
|
|
#include <unistd.h> |
| 239 |
|
|
#include <fcntl.h> |
| 240 |
|
|
#include <sys/mman.h> |
| 241 |
|
|
|
| 242 |
|
|
static caddr_t page = 0; |
| 243 |
|
|
static int page_size; |
| 244 |
|
|
static int handler_called = 0; |
| 245 |
|
|
|
| 246 |
|
|
static bool sigsegv_test_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address) |
| 247 |
|
|
{ |
| 248 |
|
|
handler_called++; |
| 249 |
|
|
if ((fault_address - 123) != page) |
| 250 |
|
|
exit(1); |
| 251 |
|
|
if (mprotect((caddr_t)((unsigned long)fault_address & -page_size), page_size, PROT_READ | PROT_WRITE) != 0) |
| 252 |
|
|
exit(1); |
| 253 |
|
|
return true; |
| 254 |
|
|
} |
| 255 |
|
|
|
| 256 |
|
|
int main(void) |
| 257 |
|
|
{ |
| 258 |
|
|
int zero_fd = open("/dev/zero", O_RDWR); |
| 259 |
|
|
if (zero_fd < 0) |
| 260 |
|
|
return 1; |
| 261 |
|
|
|
| 262 |
|
|
page_size = getpagesize(); |
| 263 |
|
|
page = (caddr_t)mmap(0, page_size, PROT_READ, MAP_PRIVATE, zero_fd, 0); |
| 264 |
|
|
if (page == MAP_FAILED) |
| 265 |
|
|
return 1; |
| 266 |
|
|
|
| 267 |
|
|
if (!sigsegv_install_handler(sigsegv_test_handler)) |
| 268 |
|
|
return 1; |
| 269 |
|
|
|
| 270 |
|
|
page[123] = 45; |
| 271 |
|
|
page[123] = 45; |
| 272 |
|
|
|
| 273 |
|
|
if (handler_called != 1) |
| 274 |
|
|
return 1; |
| 275 |
|
|
|
| 276 |
|
|
return 0; |
| 277 |
|
|
} |
| 278 |
|
|
#endif |
