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diff --git a/sysdeps/mach/hurd/hppa/trampoline.c b/sysdeps/mach/hurd/hppa/trampoline.c
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+/* Set thread_state for sighandler, and sigcontext to recover. HPPA version.
+ Copyright (C) 1995, 1997, 1998 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 Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <hurd/signal.h>
+#include "thread_state.h"
+#include <assert.h>
+#include <errno.h>
+#include "hurdfault.h"
+
+
+struct mach_msg_trap_regargs
+ {
+ /* These first four arguments are in registers 26..23. */
+ mach_msg_size_t rcv_size; /* arg3 */
+ mach_msg_size_t send_size; /* arg2 */
+ mach_msg_option_t option; /* arg1 */
+ mach_msg_header_t *msg; /* arg0 */
+ };
+
+struct sigcontext *
+_hurd_setup_sighandler (struct hurd_sigstate *ss, __sighandler_t handler,
+ int signo, long int sigcode,
+ volatile int rpc_wait,
+ struct machine_thread_all_state *state)
+{
+ __label__ trampoline, rpc_wait_trampoline;
+ void *volatile sigsp;
+ struct sigcontext *scp;
+
+ if (ss->context)
+ {
+ /* We have a previous sigcontext that sigreturn was about
+ to restore when another signal arrived. We will just base
+ our setup on that. */
+ if (_hurdsig_catch_fault (SIGSEGV))
+ assert (_hurdsig_fault_sigcode >= (long int) ss->context &&
+ _hurdsig_fault_sigcode < (long int) (ss->context + 1));
+ else
+ {
+ memcpy (&state->basic, &ss->context->sc_parisc_thread_state,
+ sizeof (state->basic));
+ state->set = (1 << PARISC_THREAD_STATE);
+ assert (! rpc_wait);
+ /* The intr_port slot was cleared before sigreturn sent us the
+ sig_post that made us notice this pending signal, so
+ _hurd_internal_post_signal wouldn't do interrupt_operation.
+ After we return, our caller will set SCP->sc_intr_port (in the
+ new context) from SS->intr_port and clear SS->intr_port. Now
+ that we are restoring this old context recorded by sigreturn,
+ we want to restore its intr_port too; so store it in
+ SS->intr_port now, so it will end up in SCP->sc_intr_port
+ later. */
+ ss->intr_port = ss->context->sc_intr_port;
+ }
+ /* If the sigreturn context was bogus, just ignore it. */
+ ss->context = NULL;
+ }
+ else if (! machine_get_basic_state (ss->thread, state))
+ return NULL;
+
+ if ((ss->actions[signo].sa_flags & SA_ONSTACK) &&
+ !(ss->sigaltstack.ss_flags & (SS_DISABLE|SS_ONSTACK)))
+ {
+ sigsp = ss->sigaltstack.ss_sp + ss->sigaltstack.ss_size;
+ ss->sigaltstack.ss_flags |= SS_ONSTACK;
+ /* XXX need to set up base of new stack for
+ per-thread variables, cthreads. */
+ }
+ else
+ sigsp = (char *) state->basic.uesp;
+
+ /* Push the signal context on the stack. */
+ sigsp -= sizeof (*scp);
+ scp = sigsp;
+
+ if (_hurdsig_catch_fault (SIGSEGV))
+ {
+ assert (_hurdsig_fault_sigcode >= (long int) scp &&
+ _hurdsig_fault_sigcode <= (long int) (scp + 1));
+ /* We got a fault trying to write the stack frame.
+ We cannot set up the signal handler.
+ Returning NULL tells our caller, who will nuke us with a SIGILL. */
+ return NULL;
+ }
+ else
+ {
+ int ok;
+
+ /* Set up the sigcontext from the current state of the thread. */
+
+ scp->sc_onstack = ss->sigaltstack.ss_flags & SS_ONSTACK ? 1 : 0;
+
+ /* struct sigcontext is laid out so that starting at sc_regs mimics a
+ struct parisc_thread_state. */
+ memcpy (&scp->sc_parisc_thread_state,
+ &state->basic, sizeof (state->basic));
+
+ _hurdsig_end_catch_fault ();
+
+ if (! ok)
+ return NULL;
+ }
+
+ /* Modify the thread state to call the trampoline code on the new stack. */
+ if (rpc_wait)
+ {
+ /* The signalee thread was blocked in a mach_msg_trap system call,
+ still waiting for a reply. We will have it run the special
+ trampoline code which retries the message receive before running
+ the signal handler.
+
+ To do this we change the OPTION argument on its stack to enable only
+ message reception, since the request message has already been
+ sent. */
+
+ struct mach_msg_trap_regargs *args = (void *) &state->basic.r23;
+
+ if (_hurdsig_catch_fault (SIGSEGV))
+ {
+ assert (_hurdsig_fault_sigcode >= (long int) args &&
+ _hurdsig_fault_sigcode < (long int) (args + 1));
+ /* Faulted accessing ARGS. Bomb. */
+ return NULL;
+ }
+
+ assert (args->option & MACH_RCV_MSG);
+ /* Disable the message-send, since it has already completed. The
+ calls we retry need only wait to receive the reply message. */
+ args->option &= ~MACH_SEND_MSG;
+
+ /* Limit the time to receive the reply message, in case the server
+ claimed that `interrupt_operation' succeeded but in fact the RPC
+ is hung. */
+ args->option |= MACH_RCV_TIMEOUT;
+ args->timeout = _hurd_interrupted_rpc_timeout;
+
+ _hurdsig_end_catch_fault ();
+
+ MACHINE_THREAD_STATE_SET_PC (&state->basic, &&rpc_wait_trampoline);
+ /* The reply-receiving trampoline code runs initially on the original
+ user stack. We pass it the signal stack pointer in %r5. */
+ state->basic.r5 = (int) sigsp;
+ /* After doing the message receive, the trampoline code will need to
+ update the %r28 value to be restored by sigreturn. To simplify
+ the assembly code, we pass the address of its slot in SCP to the
+ trampoline code in %r4. */
+ state->basic.r4 = (unsigned int) &scp->sc_regs[27];
+ /* Set up the arguments for the handler function in callee-saved
+ registers that we will move to the argument registers after
+ mach_msg_trap returns. */
+ state->basic.r6 = signo;
+ state->basic.r7 = sigcode;
+ state->basic.r8 = (unsigned int) scp;
+ }
+ else
+ {
+ MACHINE_THREAD_STATE_SET_PC (&state->basic, &&trampoline);
+ state->basic.r20 = (unsigned int) sigsp;
+ /* Set up the arguments for the handler function. */
+ state->basic.r26 = signo;
+ state->basic.r25 = sigcode;
+ state->basic.r24 = (unsigned int) scp;
+ }
+
+ /* We pass the handler function to the trampoline code in %r9. */
+ state->basic.r9 = (unsigned int) handler;
+ /* For convenience, we pass the address of __sigreturn in %r10. */
+ state->basic.r10 = (unsigned int) &__sigreturn;
+ /* The extra copy of SCP for the __sigreturn arg goes in %r8. */
+ state->basic.r10 = (unsigned int) scp;
+
+ return scp;
+
+ /* The trampoline code follows. This is not actually executed as part of
+ this function, it is just convenient to write it that way. */
+
+ rpc_wait_trampoline:
+ /* This is the entry point when we have an RPC reply message to receive
+ before running the handler. The MACH_MSG_SEND bit has already been
+ cleared in the OPTION argument on our stack. The interrupted user
+ stack pointer has not been changed, so the system call can find its
+ arguments; the signal stack pointer is in %ebx. For our convenience,
+ %ecx points to the sc_eax member of the sigcontext. */
+ asm volatile
+ (/* Retry the interrupted mach_msg system call. */
+ "ldil L%0xC0000000,%r1\nble 4(%sr7,%r1)\n"
+ "ldi -25, %r22\n" /* mach_msg_trap */
+ /* When the sigcontext was saved, %r28 was MACH_RCV_INTERRUPTED. But
+ now the message receive has completed and the original caller of
+ the RPC (i.e. the code running when the signal arrived) needs to
+ see the final return value of the message receive in %r28. So
+ store the new %r28 value into the sc_regs[27] member of the sigcontext
+ (whose address is in %r4 to make this code simpler). */
+ "stw (%r4), %r28\n"
+ /* Switch to the signal stack. */
+ "copy %r5, %r30\n"
+ /* Copy the handler arguments to the argument registers. */
+ "copy %r6, %r26\n"
+ "copy %r7, %r25\n"
+ "copy %r8, %r24\n"
+ );
+
+ trampoline:
+ /* Entry point for running the handler normally. The arguments to the
+ handler function are already in the argument registers. */
+ asm volatile
+ ("bv (%r9); nop" /* Call the handler function. */
+ "bv (%r10)\n" /* Call __sigreturn (SCP); never returns. */
+ "copy %r8, %r26" /* Set up arg in delay slot. */
+ : : "i" (&__sigreturn));
+
+ /* NOTREACHED */
+ return NULL;
+}