diff options
| -rw-r--r-- | ChangeLog | 30 | ||||
| -rw-r--r-- | hurd/catch-signal.c | 87 | ||||
| -rw-r--r-- | hurd/hurdsig.c | 77 | ||||
| -rw-r--r-- | hurd/intr-msg.c | 24 |
4 files changed, 185 insertions, 33 deletions
@@ -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. diff --git a/hurd/catch-signal.c b/hurd/catch-signal.c new file mode 100644 index 0000000..3e8ee6c --- /dev/null +++ b/hurd/catch-signal.c @@ -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); +} diff --git a/hurd/hurdsig.c b/hurd/hurdsig.c index 290dba8..6085ab1 100644 --- a/hurd/hurdsig.c +++ b/hurd/hurdsig.c @@ -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; } diff --git a/hurd/intr-msg.c b/hurd/intr-msg.c index 41f43e1..9362731 100644 --- a/hurd/intr-msg.c +++ b/hurd/intr-msg.c @@ -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" @@ -45,7 +46,7 @@ _hurd_intr_rpc_mach_msg (mach_msg_header_t *msg, return EINTR when some other thread gets a signal, in which case we want to restart our call. */ ss->intr_port = msg->msgh_remote_port; - + /* A signal may arrive here, after intr_port is set, but before the mach_msg system call. The signal handler might do an interruptible RPC, and clobber intr_port; then it would not be @@ -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. */ |