/* SS->thread is suspended. Abort the thread and get its basic state. */
static void
abort_thread (struct hurd_sigstate *ss, struct machine_thread_all_state *state,
void (*reply) (void))
{
if (!(state->set & THREAD_ABORTED))
{
error_t err = __thread_abort (ss->thread);
assert_perror (err);
/* Clear all thread state flavor set bits, because thread_abort may
have changed the state. */
state->set = THREAD_ABORTED;
}
if (reply)
(*reply) ();
machine_get_basic_state (ss->thread, state);
}
struct sigcontext *
_hurd_setup_sighandler (struct hurd_sigstate *ss, __sighandler_t handler,
int signo, struct hurd_signal_detail *detail,
volatile int rpc_wait,
struct machine_thread_all_state *state)
{
void trampoline (void);
void rpc_wait_trampoline (void);
void firewall (void);
extern const void _hurd_intr_rpc_msg_in_trap;
extern const void _hurd_intr_rpc_msg_cx_sp;
extern const void _hurd_intr_rpc_msg_sp_restored;
void *volatile sigsp;
struct sigcontext *scp;
struct
{
int signo;
long int sigcode;
struct sigcontext *scp; /* Points to ctx, below. */
void *sigreturn_addr;
void *sigreturn_returns_here;
struct sigcontext *return_scp; /* Same; arg to sigreturn. */
struct sigcontext ctx;
struct hurd_userlink link;
} *stackframe;
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_memory_fault (ss->context))
{
memcpy (&state->basic, &ss->context->sc_i386_thread_state,
sizeof (state->basic));
memcpy (&state->fpu, &ss->context->sc_i386_float_state,
sizeof (state->fpu));
state->set |= (1 << i386_THREAD_STATE) | (1 << i386_FLOAT_STATE);
}
}
if (! machine_get_basic_state (ss->thread, state))
return NULL;
/* Save the original SP in the gratuitous `esp' slot.
We may need to reset the SP (the `uesp' slot) to avoid clobbering an
interrupted RPC frame. */
state->basic.esp = state->basic.uesp;
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. */
}
/* This code has intimate knowledge of the special mach_msg system call
done in intr-msg.c; that code does (see intr-msg.h):
movl %esp, %ecx
leal ARGS, %esp
_hurd_intr_rpc_msg_cx_sp: movl $-25, %eax
_hurd_intr_rpc_msg_do_trap: lcall $7, $0
_hurd_intr_rpc_msg_in_trap: movl %ecx, %esp
_hurd_intr_rpc_msg_sp_restored:
We must check for the window during which %esp points at the
mach_msg arguments. The space below until %ecx is used by
the _hurd_intr_rpc_mach_msg frame, and must not be clobbered. */
else if (state->basic.eip >= (int) &_hurd_intr_rpc_msg_cx_sp &&
state->basic.eip < (int) &_hurd_intr_rpc_msg_sp_restored)
/* The SP now points at the mach_msg args, but there is more stack
space used below it. The real SP is saved in %ecx; we must push the
new frame below there, and restore that value as the SP on
sigreturn. */
sigsp = (char *) (state->basic.uesp = state->basic.ecx);
else
sigsp = (char *) state->basic.uesp;
/* Push the arguments to call `trampoline' on the stack. */
sigsp -= sizeof (*stackframe);
stackframe = sigsp;
if (_hurdsig_catch_memory_fault (stackframe))
{
/* 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;
extern void _hurdsig_longjmp_from_handler (void *, jmp_buf, int);
/* Add a link to the thread's active-resources list. We mark this as
the only user of the "resource", so the cleanup function will be
called by any longjmp which is unwinding past the signal frame.
The cleanup function (in sigunwind.c) will make sure that all the
appropriate cleanups done by sigreturn are taken care of. */
stackframe->link.cleanup = &_hurdsig_longjmp_from_handler;
stackframe->link.cleanup_data = &stackframe->ctx;
stackframe->link.resource.next = NULL;
stackframe->link.resource.prevp = NULL;
stackframe->link.thread.next = ss->active_resources;
stackframe->link.thread.prevp = &ss->active_resources;
if (stackframe->link.thread.next)
stackframe->link.thread.next->thread.prevp
= &stackframe->link.thread.next;
ss->active_resources = &stackframe->link;
/* Set up the arguments for the signal handler. */
stackframe->signo = signo;
stackframe->sigcode = detail->code;
stackframe->scp = stackframe->return_scp = scp = &stackframe->ctx;
stackframe->sigreturn_addr = &__sigreturn;
stackframe->sigreturn_returns_here = firewall; /* Crash on return. */
/* 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_gs mimics a
struct i386_thread_state. */
memcpy (&scp->sc_i386_thread_state,
&state->basic, sizeof (state->basic));
/* struct sigcontext is laid out so that starting at sc_fpkind mimics
a struct i386_float_state. */
ok = machine_get_state (ss->thread, state, i386_FLOAT_STATE,
&state->fpu, &scp->sc_i386_float_state,
sizeof (state->fpu));
_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_args *args = (void *) state->basic.esp;
if (_hurdsig_catch_memory_fault (args))
{
/* 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 ();
state->basic.eip = (int) rpc_wait_trampoline;
/* The reply-receiving trampoline code runs initially on the original
user stack. We pass it the signal stack pointer in %ebx. */
state->basic.uesp = state->basic.esp; /* Restore mach_msg syscall SP. */
state->basic.ebx = (int) sigsp;
/* After doing the message receive, the trampoline code will need to
update the %eax 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 %ecx. */
state->basic.ecx = (int) &scp->sc_eax;
}
else
{
state->basic.eip = (int) trampoline;
state->basic.uesp = (int) sigsp;
}
/* We pass the handler function to the trampoline code in %edx. */
state->basic.edx = (int) handler;
/* The x86 ABI says the DF bit is clear on entry to any function. */
state->basic.efl &= ~EFL_DF;
return scp;
}
struct sigcontext *
_hurd_setup_sighandler (struct hurd_sigstate *ss, __sighandler_t handler,
int signo, struct hurd_signal_detail *detail,
volatile int rpc_wait,
struct machine_thread_all_state *state)
{
void trampoline (void);
void rpc_wait_trampoline (void);
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_memory_fault (ss->context))
{
memcpy (&state->basic, &ss->context->sc_ppc_thread_state,
sizeof (state->basic));
memcpy (&state->exc, &ss->context->sc_ppc_exc_state,
sizeof (state->exc));
memcpy (&state->fpu, &ss->context->sc_ppc_float_state,
sizeof (state->fpu));
state->set = (1 << PPC_THREAD_STATE) | (1 << PPC_EXCEPTION_STATE)
| (1 << PPC_FLOAT_STATE);
}
}
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.SP;
/* Set up the sigcontext structure on the stack. This is all the stack
needs, since the args are passed in registers (below). */
sigsp -= sizeof (*scp);
scp = sigsp;
sigsp -= 16; /* Reserve some space for a stack frame. */
if (_hurdsig_catch_memory_fault (scp))
{
/* 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_srr0
mimics a struct ppc_thread_state. */
memcpy (&scp->sc_ppc_thread_state,
&state->basic, sizeof (state->basic));
/* struct sigcontext is laid out so that starting at sc_dar
mimics a struct ppc_exc_state. */
ok = machine_get_state (ss->thread, state, PPC_EXCEPTION_STATE,
&state->exc, &scp->sc_ppc_exc_state,
sizeof (state->exc));
/* struct sigcontext is laid out so that starting at sc_fprs[0]
mimics a struct ppc_float_state. */
if (ok)
ok = machine_get_state (ss->thread, state, PPC_FLOAT_STATE,
&state->fpu, &scp->sc_ppc_float_state,
sizeof (state->fpu));
_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 in its registers to
enable only message reception, since the request message has
already been sent. */
/* The system call arguments are stored in consecutive registers
starting with r3. */
struct mach_msg_trap_args *args = (void *) &state->basic.r3;
if (_hurdsig_catch_memory_fault (args))
{
/* 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 ();
state->basic.PC = (int) rpc_wait_trampoline;
/* After doing the message receive, the trampoline code will need to
update the r3 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 r10. */
state->basic.r10 = (long int) &scp->sc_gprs[3];
/* We must preserve the mach_msg_trap args in r3..r9.
Pass the handler args to the trampoline code in r11..r13. */
state->basic.r11 = signo;
state->basic.r12 = detail->code;
state->basic.r13 = (int) scp;
}
else
{
state->basic.PC = (int) trampoline;
state->basic.r3 = signo;
state->basic.r4 = detail->code;
state->basic.r5 = (int) scp;
}
state->basic.r1 = (int) sigsp; /* r1 is the stack pointer. */
/* We pass the handler function to the trampoline code in ctr. */
state->basic.ctr = (int) handler;
/* In r15, we store the address of __sigreturn itself,
for the trampoline code to use. */
state->basic.r15 = (int) &__sigreturn;
/* In r16, we save the SCP value to pass to __sigreturn
after the handler returns. */
state->basic.r16 = (int) scp;
/* In r3, we store a pointer to the registers in STATE so that the
trampoline code can load the registers from that. For some reason,
thread_set_state doesn't set all registers. */
state->basic.r17 = state->basic.r3; /* Store the real r3 in r17. */
state->basic.r3 = (int) &state->basic.r0;
return scp;
}
struct sigcontext *
_hurd_setup_sighandler (struct hurd_sigstate *ss, __sighandler_t handler,
int signo, struct hurd_signal_detail *detail,
volatile int rpc_wait,
struct machine_thread_all_state *state)
{
__label__ trampoline, rpc_wait_trampoline, firewall;
void *volatile sigsp;
struct sigcontext *scp;
struct
{
int signo;
long int sigcode;
struct sigcontext *scp; /* Points to ctx, below. */
void *sigreturn_addr;
void *sigreturn_returns_here;
struct sigcontext *return_scp; /* Same; arg to sigreturn. */
struct sigcontext ctx;
struct hurd_userlink link;
} *stackframe;
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_memory_fault (ss->context))
{
memcpy (&state->basic, &ss->context->sc_mips_thread_state,
sizeof (state->basic));
memcpy (&state->exc, &ss->context->sc_mips_exc_state,
sizeof (state->exc));
state->set = (1 << MIPS_THREAD_STATE) | (1 << MIPS_EXC_STATE);
if (state->exc.coproc_state & SC_COPROC_USE_FPU)
{
memcpy (&state->fpu, &ss->context->sc_mips_float_state,
sizeof (state->fpu));
state->set |= (1 << MIPS_FLOAT_STATE);
}
}
}
if (! machine_get_basic_state (ss->thread, state))
return NULL;
/* Save the original SP in the gratuitous s0 ($16) slot.
We may need to reset the SP (the `r29' slot) to avoid clobbering an
interrupted RPC frame. */
state->basic.r16 = state->basic.r29;
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.r29;
/* Push the arguments to call `trampoline' on the stack. */
sigsp -= sizeof (*stackframe);
stackframe = sigsp;
if (_hurdsig_catch_memory_fault (stackframe))
{
/* 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;
extern void _hurdsig_longjmp_from_handler (void *, jmp_buf, int);
/* Add a link to the thread's active-resources list. We mark this as
the only user of the "resource", so the cleanup function will be
called by any longjmp which is unwinding past the signal frame.
The cleanup function (in sigunwind.c) will make sure that all the
appropriate cleanups done by sigreturn are taken care of. */
stackframe->link.cleanup = &_hurdsig_longjmp_from_handler;
stackframe->link.cleanup_data = &stackframe->ctx;
stackframe->link.resource.next = NULL;
stackframe->link.resource.prevp = NULL;
stackframe->link.thread.next = ss->active_resources;
stackframe->link.thread.prevp = &ss->active_resources;
if (stackframe->link.thread.next)
stackframe->link.thread.next->thread.prevp
= &stackframe->link.thread.next;
ss->active_resources = &stackframe->link;
/* Set up the arguments for the signal handler. */
stackframe->signo = signo;
stackframe->sigcode = detail->code;
stackframe->scp = stackframe->return_scp = scp = &stackframe->ctx;
stackframe->sigreturn_addr = &__sigreturn;
stackframe->sigreturn_returns_here = &&firewall; /* Crash on return. */
/* 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_gpr
mimics a struct mips_thread_state. */
memcpy (&scp->sc_mips_thread_state,
&state->basic, sizeof (state->basic));
/* struct sigcontext is laid out so that starting at sc_cause
mimics a struct mips_exc_state. */
ok = machine_get_state (ss->thread, state, MIPS_EXC_STATE,
&state->exc, &scp->sc_cause,
sizeof (state->exc));
if (ok && (scp->sc_coproc_used & SC_COPROC_USE_FPU))
/* struct sigcontext is laid out so that starting at sc_fpr
mimics a struct mips_float_state. This state
is only meaningful if the coprocessor was used. */
ok = machine_get_state (ss->thread, state, MIPS_FLOAT_STATE,
&state->fpu, &scp->sc_mips_float_state,
sizeof (state->fpu));
_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 in its registers to
enable only message reception, since the request message has
already been sent. */
/* The system call arguments are stored in consecutive registers
starting with a0 ($4). */
struct mach_msg_trap_args *args = (void *) &state->basic.r4;
if (_hurdsig_catch_memory_fault (args))
{
/* 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 ();
state->basic.pc = (int) &&rpc_wait_trampoline;
/* The reply-receiving trampoline code runs initially on the original
user stack. We pass it the signal stack pointer in s4 ($20). */
state->basic.r29 = state->basic.r16; /* Restore mach_msg syscall SP. */
state->basic.r20 = (int) sigsp;
/* After doing the message receive, the trampoline code will need to
update the v0 ($2) 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 s5 ($21). */
state->basic.r21 = (int) &scp->sc_gpr[1];
/* We must preserve the mach_msg_trap args in a0..t2 ($4..$10).
Pass the handler args to the trampoline code in s1..s3 ($17..$19). */
state->basic.r17 = signo;
state->basic.r18 = detail->code;
state->basic.r19 = (int) scp;
}
else
{
