static void
faulthandler_user(int signum)
{
user_signal_t *user;
int save_errno = errno;
user = &user_signals[signum];
if (!user->enabled)
return;
faulthandler_dump_traceback(user->fd, user->all_threads, user->interp);
#ifdef HAVE_SIGACTION
if (user->chain) {
(void)sigaction(signum, &user->previous, NULL);
errno = save_errno;
/* call the previous signal handler */
raise(signum);
save_errno = errno;
(void)faulthandler_register(signum, user->chain, NULL);
errno = save_errno;
}
#else
if (user->chain) {
errno = save_errno;
/* call the previous signal handler */
user->previous(signum);
}
#endif
}
static LONG WINAPI
faulthandler_exc_handler(struct _EXCEPTION_POINTERS *exc_info)
{
const int fd = fatal_error.fd;
DWORD code = exc_info->ExceptionRecord->ExceptionCode;
DWORD flags = exc_info->ExceptionRecord->ExceptionFlags;
/* only log fatal exceptions */
if (flags & EXCEPTION_NONCONTINUABLE) {
/* call the next exception handler */
return EXCEPTION_CONTINUE_SEARCH;
}
PUTS(fd, "Windows fatal exception: ");
switch (code)
{
/* only format most common errors */
case EXCEPTION_ACCESS_VIOLATION: PUTS(fd, "access violation"); break;
case EXCEPTION_FLT_DIVIDE_BY_ZERO: PUTS(fd, "float divide by zero"); break;
case EXCEPTION_FLT_OVERFLOW: PUTS(fd, "float overflow"); break;
case EXCEPTION_INT_DIVIDE_BY_ZERO: PUTS(fd, "int divide by zero"); break;
case EXCEPTION_INT_OVERFLOW: PUTS(fd, "integer overflow"); break;
case EXCEPTION_IN_PAGE_ERROR: PUTS(fd, "page error"); break;
case EXCEPTION_STACK_OVERFLOW: PUTS(fd, "stack overflow"); break;
default:
PUTS(fd, "code ");
_Py_DumpDecimal(fd, code);
}
PUTS(fd, "\n\n");
if (code == EXCEPTION_ACCESS_VIOLATION) {
/* disable signal handler for SIGSEGV */
size_t i;
for (i=0; i < faulthandler_nsignals; i++) {
fault_handler_t *handler = &faulthandler_handlers[i];
if (handler->signum == SIGSEGV) {
faulthandler_disable_fatal_handler(handler);
break;
}
}
}
faulthandler_dump_traceback(fd, fatal_error.all_threads,
fatal_error.interp);
/* call the next exception handler */
return EXCEPTION_CONTINUE_SEARCH;
}
static void
faulthandler_fatal_error(int signum)
{
const int fd = fatal_error.fd;
unsigned int i;
fault_handler_t *handler = NULL;
int save_errno = errno;
if (!fatal_error.enabled)
return;
for (i=0; i < faulthandler_nsignals; i++) {
handler = &faulthandler_handlers[i];
if (handler->signum == signum)
break;
}
if (handler == NULL) {
/* faulthandler_nsignals == 0 (unlikely) */
return;
}
/* restore the previous handler */
#ifdef HAVE_SIGACTION
(void)sigaction(signum, &handler->previous, NULL);
#else
(void)signal(signum, handler->previous);
#endif
handler->enabled = 0;
PUTS(fd, "Fatal Python error: ");
PUTS(fd, handler->name);
PUTS(fd, "\n\n");
faulthandler_dump_traceback(fd, fatal_error.all_threads,
fatal_error.interp);
errno = save_errno;
#ifdef MS_WINDOWS
if (signum == SIGSEGV) {
/* don't explicitly call the previous handler for SIGSEGV in this signal
handler, because the Windows signal handler would not be called */
return;
}
#endif
/* call the previous signal handler: it is called immediately if we use
sigaction() thanks to SA_NODEFER flag, otherwise it is deferred */
raise(signum);
}
