glibc/hurd/hurdfault.c
1995-02-18 01:27:10 +00:00

144 lines
4.3 KiB
C

/* Handle faults in the signal thread.
Copyright (C) 1994 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <hurd.h>
#include <hurd/signal.h>
#include "hurdfault.h"
#include <errno.h>
#include <string.h>
#include <setjmp.h>
#include <stdio.h>
#include "thread_state.h"
#include "faultexc.h" /* mig-generated header for our exc server. */
jmp_buf _hurdsig_fault_env;
static mach_port_t forward_sigexc;
int _hurdsig_fault_expect_signo;
long int _hurdsig_fault_sigcode;
int _hurdsig_fault_sigerror;
kern_return_t
_hurdsig_fault_catch_exception_raise (mach_port_t port,
thread_t thread,
task_t task,
int exception,
int code,
int subcode)
{
int signo;
if (port != forward_sigexc ||
thread != _hurd_msgport_thread || task != __mach_task_self ())
return EPERM; /* Strange bogosity. */
/* Call the machine-dependent function to translate the Mach exception
codes into a signal number and subcode. */
_hurd_exception2signal (exception, code, subcode, &signo,
&_hurdsig_fault_sigcode, &_hurdsig_fault_sigerror);
return signo == _hurdsig_fault_expect_signo ? 0 : EGREGIOUS;
}
static void
faulted (void)
{
struct
{
mach_msg_header_t head;
char buf[64];
} request;
struct
{
mach_msg_header_t head;
mach_msg_type_t type;
int result;
} reply;
extern int _hurdsig_fault_exc_server (mach_msg_header_t *,
mach_msg_header_t *);
/* Wait for the exception_raise message forwarded by the proc server. */
if (__mach_msg (&request.head, MACH_RCV_MSG, 0,
sizeof request, forward_sigexc,
MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL)
!= MACH_MSG_SUCCESS)
__libc_fatal ("msg receive failed on signal thread exc\n");
/* Run the exc demuxer which should call the server function above.
That function returns 0 if the exception was expected. */
switch (_hurdsig_fault_exc_server (&request.head, &reply.head))
{
case KERN_SUCCESS:
if (reply.head.msgh_remote_port != MACH_PORT_NULL)
__mach_msg (&reply.head, MACH_SEND_MSG, reply.head.msgh_size,
0, MACH_PORT_NULL, MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
break;
default:
__mach_msg_destroy (&request.head);
case MIG_NO_REPLY:
}
_hurdsig_fault_expect_signo = 0;
longjmp (_hurdsig_fault_env, 1);
}
static char faultstack[1024];
/* Send exceptions for the signal thread to the proc server.
It will forward the message on to our message port,
and then restore the thread's state to code which
does `longjmp (_hurd_sigthread_fault_env, 1)'. */
void
_hurdsig_fault_init (void)
{
error_t err;
struct machine_thread_state state;
mach_port_t sigexc;
if (err = __mach_port_allocate (__mach_task_self (),
MACH_PORT_RIGHT_RECEIVE, &sigexc))
__libc_fatal ("hurd: Can't create receive right for signal thread exc\n");
if (err = __mach_port_allocate (__mach_task_self (),
MACH_PORT_RIGHT_RECEIVE, &forward_sigexc))
__libc_fatal ("hurd: Can't create receive right for signal thread exc\n");
memset (&state, 0, sizeof state);
MACHINE_THREAD_STATE_SET_PC (&state, faulted);
MACHINE_THREAD_STATE_SET_SP (&state, faultstack, sizeof faultstack);
#if 0 /* Don't confuse gdb. */
__thread_set_special_port (_hurd_msgport_thread,
THREAD_EXCEPTION_PORT, sigexc);
#endif
if (err = __USEPORT
(PROC,
__proc_handle_exceptions (port,
sigexc,
forward_sigexc, MACH_MSG_TYPE_MAKE_SEND,
MACHINE_THREAD_STATE_FLAVOR,
(natural_t *) &state,
MACHINE_THREAD_STATE_COUNT)))
__libc_fatal ("hurd: proc won't handle signal thread exceptions\n");
}