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-rw-r--r--hurd/hurdfault.c143
1 files changed, 143 insertions, 0 deletions
diff --git a/hurd/hurdfault.c b/hurd/hurdfault.c
new file mode 100644
index 0000000000..e8b54660b9
--- /dev/null
+++ b/hurd/hurdfault.c
@@ -0,0 +1,143 @@
+/* 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");
+}
+