Initial revision
authorroland <roland>
Sun, 4 Sep 1994 04:57:08 +0000 (04:57 +0000)
committerroland <roland>
Sun, 4 Sep 1994 04:57:08 +0000 (04:57 +0000)
hurd/hurdfault.c [new file with mode: 0644]

diff --git a/hurd/hurdfault.c b/hurd/hurdfault.c
new file mode 100644 (file)
index 0000000..14a465f
--- /dev/null
@@ -0,0 +1,135 @@
+/* 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/fault.h>
+#include <string.h>
+#include <setjmp.h>
+#include "thread_state.h"
+
+jmp_buf _hurdsig_fault_env;
+
+static mach_port_t forward_sigexc;
+
+int _hurdsig_fault_expect_signo;
+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, sigcode, error;
+
+  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_error);
+
+  return signo == _hurdsig_fault_expect_signo ? 0 : EGREGIOUS;
+}
+
+static void
+faulted (void)
+{
+  struct
+    {
+      mach_msg_header_t header;
+      char buf[64];
+    } request;
+  struct
+    {
+      mach_msg_header_t header;
+      mach_msg_type_t type;
+      int result;
+    } reply;
+
+ /* Wait for the exception_raise message forwarded by the proc server.  */
+
+ if (__mach_msg (&request->head, MACH_RCV_MSG, 0,
+                 sizeof request, 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->header.msgh_remote_port != MACH_PORT_NULL)
+       __mach_msg (&reply->head, MACH_SEND_MSG, reply->header.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_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,
+                                (int *) &state, MACHINE_THREAD_STATE_COUNT)))
+    __libc_fatal ("hurd: proc won't handle signal thread exceptions\n");
+}
+