Wed Jan 3 20:23:42 1996 Roland McGrath <roland@churchy.gnu.ai.mit.edu>

* hurd/catch-signal.c: New file.

	* hurd/intr-msg.c: When restarting RPC, fetch a new reply port.

	* hurd/hurdsig.c: Use new hurdfault.h interface.
	(abort_all_rpcs): Mutate return value to EINTR in threads whose
	replies we will wait for.

	* hurd/hurdkill.c (_hurd_sig_post): When doing pgrp, make sure we
	do ourselves last.

Wed Jan  3 19:17:10 1996  Miles Bader  <miles@gnu.ai.mit.edu>

	* sysdeps/mach/hurd/access.c (__access): Put the uid/gid arguments
	to auth_makeauth() in the right order.

Wed Jan  3 17:19:04 1996  Roland McGrath  <roland@churchy.gnu.ai.mit.edu>

	* sysdeps/generic/strsep.c: Rewritten.

	* sysdeps/mach/hurd/fork.c: Use a different workaround for the
 	suspended page fault deadlock kernel bug: thread_abort our signal
 	thread first thing after proc_dostop.

	* sysdeps/mach/hurd/setgid.c: Rewrote gid frobnication to
	recognize rootness properly.

	* hurd/hurdsig.c: Use new signal preemption interface.
This commit is contained in:
Roland McGrath 1996-01-04 10:00:22 +00:00
parent 67f27f3a02
commit fb8e70d6dd
4 changed files with 185 additions and 33 deletions

View File

@ -1,3 +1,32 @@
Wed Jan 3 20:23:42 1996 Roland McGrath <roland@churchy.gnu.ai.mit.edu>
* hurd/catch-signal.c: New file.
* hurd/intr-msg.c: When restarting RPC, fetch a new reply port.
* hurd/hurdsig.c: Use new hurdfault.h interface.
(abort_all_rpcs): Mutate return value to EINTR in threads whose
replies we will wait for.
* hurd/hurdkill.c (_hurd_sig_post): When doing pgrp, make sure we
do ourselves last.
Wed Jan 3 19:17:10 1996 Miles Bader <miles@gnu.ai.mit.edu>
* sysdeps/mach/hurd/access.c (__access): Put the uid/gid arguments
to auth_makeauth() in the right order.
Wed Jan 3 17:19:04 1996 Roland McGrath <roland@churchy.gnu.ai.mit.edu>
* sysdeps/generic/strsep.c: Rewritten.
* sysdeps/mach/hurd/fork.c: Use a different workaround for the
suspended page fault deadlock kernel bug: thread_abort our signal
thread first thing after proc_dostop.
* sysdeps/mach/hurd/setgid.c: Rewrote gid frobnication to
recognize rootness properly.
Tue Jan 2 00:50:10 1996 Roland McGrath <roland@churchy.gnu.ai.mit.edu>
* hurd/hurd/signal.h (struct hurd_sigstate): New member `preempters'.
@ -6,6 +35,7 @@ Tue Jan 2 00:50:10 1996 Roland McGrath <roland@churchy.gnu.ai.mit.edu>
* hurd/preempt-sig.c: Rewritten with new interface.
* sysdeps/mach/hurd/jmp-unwind.c (_longjmp_unwind): Remove local signal
preempters being unwound past.
* hurd/hurdsig.c: Use new signal preemption interface.
* db: New directory, 4.4 BSD db package incorporated from BSD db-1.85
release.

87
hurd/catch-signal.c Normal file
View File

@ -0,0 +1,87 @@
/* Convenience function to catch expected signals during an operation.
Copyright (C) 1996 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/signal.h>
#include <hurd/sigpreempt.h>
#include <string.h>
#include <assert.h>
error_t
hurd_catch_signal (sigset_t sigset,
unsigned long int first, unsigned long int last,
error_t (*operate) (struct hurd_signal_preempter *),
sighandler_t handler)
{
jmp_buf buf;
void throw (int signo, long int sigcode, struct sigcontext *scp)
{ longjmp (buf, scp->sc_error ?: EGRATUITOUS); }
struct hurd_signal_preempter preempter =
{
sigset, first, last,
NULL, handler == SIG_ERR ? (sighandler_t) &throw : handler,
};
struct hurd_sigstate *const ss = _hurd_self_sigstate ();
error_t error;
if (handler == SIG_ERR)
/* Not our handler; don't bother saving state. */
error = 0;
else
/* This returns again with nonzero value when we preempt a signal. */
error = setjmp (buf);
if (error == 0)
{
/* Install a signal preempter for the thread. */
__spin_lock (&ss->lock);
preempter.next = ss->preempters;
ss->preempters = &preempter;
__spin_unlock (&ss->lock);
/* Try the operation that might crash. */
(*operate) (&preempter);
}
/* Either FUNCTION completed happily and ERROR is still zero, or it hit
an expected signal and `throw' made setjmp return the signal error
code in ERROR. Now we can remove the preempter and return. */
__spin_lock (&ss->lock);
assert (ss->preempters == &preempter);
ss->preempters = preempter.next;
__spin_unlock (&ss->lock);
return error;
}
error_t
hurd_safe_memset (void *dest, int byte, size_t nbytes)
{
error_t operate (struct hurd_signal_preempter *preempter)
{
memset (dest, byte, nbytes);
return 0;
}
return hurd_catch_signal (sigmask (SIGBUS) | sigmask (SIGSEGV),
(vm_address_t) dest, (vm_address_t) dest + nbytes,
&operate, SIG_ERR);
}

View File

@ -121,8 +121,9 @@ _hurd_thread_sigstate (thread_t thread)
#include "thread_state.h"
#include <hurd/msg_server.h>
#include <hurd/msg_reply.h> /* For __msg_sig_post_reply. */
#include <assert.h>
#include <hurd/interrupt.h>
#include <assert.h>
#include <unistd.h>
int _hurd_core_limit; /* XXX */
@ -216,12 +217,9 @@ interrupted_reply_port_location (struct machine_thread_all_state *thread_state,
mach_port_t *portloc = (mach_port_t *) __hurd_threadvar_location_from_sp
(_HURD_THREADVAR_MIG_REPLY, (void *) thread_state->basic.SP);
if (sigthread && _hurdsig_catch_fault (SIGSEGV))
{
assert (_hurdsig_fault_sigcode == (long int) portloc);
/* Faulted trying to read the stack. */
return NULL;
}
if (sigthread && _hurdsig_catch_memory_fault (portloc))
/* Faulted trying to read the stack. */
return NULL;
/* Fault now if this pointer is bogus. */
*(volatile mach_port_t *) portloc = *portloc;
@ -363,9 +361,9 @@ abort_all_rpcs (int signo, struct machine_thread_all_state *state, int live)
reply_ports = alloca (nthreads * sizeof *reply_ports);
nthreads = 0;
for (ss = _hurd_sigstates; ss != NULL; ss = ss->next)
for (ss = _hurd_sigstates; ss != NULL; ss = ss->next, ++nthreads)
if (ss->thread == _hurd_msgport_thread)
reply_ports[nthreads++] = MACH_PORT_NULL;
reply_ports[nthreads] = MACH_PORT_NULL;
else
{
int state_changed;
@ -374,15 +372,26 @@ abort_all_rpcs (int signo, struct machine_thread_all_state *state, int live)
/* Abort any operation in progress with interrupt_operation.
Record the reply port the thread is waiting on.
We will wait for all the replies below. */
reply_ports[nthreads++] = _hurdsig_abort_rpcs (ss, signo, 1,
state, &state_changed,
NULL);
if (state_changed && live)
/* Aborting the RPC needed to change this thread's state,
and it might ever run again. So write back its state. */
__thread_set_state (ss->thread, MACHINE_THREAD_STATE_FLAVOR,
(natural_t *) &state->basic,
MACHINE_THREAD_STATE_COUNT);
reply_ports[nthreads] = _hurdsig_abort_rpcs (ss, signo, 1,
state, &state_changed,
NULL);
if (live)
{
if (reply_ports[nthreads] != MACH_PORT_NULL)
{
/* We will wait for the reply to this RPC below, so the
thread must issue a new RPC rather than waiting for the
reply to the one it sent. */
state->basic.SYSRETURN = EINTR;
state_changed = 1;
}
if (state_changed)
/* Aborting the RPC needed to change this thread's state,
and it might ever run again. So write back its state. */
__thread_set_state (ss->thread, MACHINE_THREAD_STATE_FLAVOR,
(natural_t *) &state->basic,
MACHINE_THREAD_STATE_COUNT);
}
}
/* Wait for replies from all the successfully interrupted RPCs. */
@ -744,10 +753,8 @@ _hurd_internal_post_signal (struct hurd_sigstate *ss,
mach_port_t *loc;
if (_hurdsig_catch_fault (SIGSEGV))
if (_hurdsig_catch_memory_fault (ss->context))
{
assert (_hurdsig_fault_sigcode >= (long int) ss->context &&
_hurdsig_fault_sigcode < (long int) (ss->context + 1));
/* We faulted reading the thread's stack. Forget that
context and pretend it wasn't there. It almost
certainly crash if this handler returns, but that's it's
@ -1176,14 +1183,34 @@ text_set_element (_hurd_reauth_hook, reauth_proc);
const char *
_hurdsig_getenv (const char *variable)
{
if (_hurdsig_catch_fault (SIGSEGV))
if (_hurdsig_catch_memory_fault (__environ))
/* We bombed in getenv. */
return NULL;
else
{
const char *value = getenv (variable);
/* Fault now if VALUE is a bogus string. */
(void) strlen (value);
const size_t len = strlen (variable);
char *value = NULL;
char *volatile *ep = __environ;
while (*ep)
{
const char *p = *ep;
_hurdsig_fault_preempter.first = (long int) p;
_hurdsig_fault_preempter.last = VM_MAX_ADDRESS;
if (! strncmp (p, variable, len) && p[len] == '=')
{
char *value;
size_t valuelen;
p += len + 1;
valuelen = strlen (p);
_hurdsig_fault_preempter.last = (long int) (p + valuelen);
value = malloc (++valuelen);
if (value)
memcpy (value, p, valuelen);
break;
}
_hurdsig_fault_preempter.first = (long int) ++ep;
_hurdsig_fault_preempter.last = (long int) (ep + 1);
}
_hurdsig_end_catch_fault ();
return value;
}

View File

@ -1,5 +1,5 @@
/* Replacement for mach_msg used in interruptible Hurd RPCs.
Copyright (C) 1995 Free Software Foundation, Inc.
Copyright (C) 1995, 1996 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
@ -19,6 +19,7 @@ Cambridge, MA 02139, USA. */
#include <mach.h>
#include <mach/mig_errors.h>
#include <mach/mig_support.h>
#include <hurd/signal.h>
#include "intr-msg.h"
@ -58,12 +59,12 @@ _hurd_intr_rpc_mach_msg (mach_msg_header_t *msg,
if (ss->cancel)
{
err = EINTR;
ss->cancel = 0;
return EINTR;
}
else
err = INTR_MSG_TRAP (msg, option, send_size,
rcv_size, rcv_name, timeout, notify);
err = INTR_MSG_TRAP (msg, option, send_size,
rcv_size, rcv_name, timeout, notify);
switch (err)
{
@ -83,7 +84,14 @@ _hurd_intr_rpc_mach_msg (mach_msg_header_t *msg,
signal thread will have cleared SS->intr_port.
Since it's not cleared, the signal was for another thread,
or SA_RESTART is set. Restart the interrupted call. */
goto message;
{
restart:
if (rcv_name != MACH_PORT_NULL)
/* Make sure we have a valid reply port. The one we were using
may have been destroyed by interruption. */
msg->msgh_local_port = rcv_name = __mig_get_reply_port ();
goto message;
}
/* FALLTHROUGH */
case MACH_RCV_PORT_DIED:
@ -139,7 +147,7 @@ _hurd_intr_rpc_mach_msg (mach_msg_header_t *msg,
if (ss->intr_port != MACH_PORT_NULL)
/* Nope; repeat the RPC.
XXX Resources moved? */
goto message;
goto restart;
else
/* The EINTR return indicates cancellation, so clear the
flag. */