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/****************************************************************************
* *
* GNAT COMPILER COMPONENTS *
* *
* I N I T *
* *
* C Implementation File *
* *
* Copyright (C) 1992-2006, Free Software Foundation, Inc. *
* *
* GNAT is free software; you can redistribute it and/or modify it under *
* terms of the GNU General Public License as published by the Free Soft- *
* ware Foundation; either version 2, or (at your option) any later ver- *
* sion. GNAT is distributed in the hope that it will be useful, but WITH- *
* OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY *
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License *
* for more details. You should have received a copy of the GNU General *
* Public License distributed with GNAT; see file COPYING. If not, write *
* to the Free Software Foundation, 51 Franklin Street, Fifth Floor, *
* Boston, MA 02110-1301, USA. *
* *
* As a special exception, if you link this file with other files to *
* produce an executable, this file does not by itself cause the resulting *
* executable to be covered by the GNU General Public License. This except- *
* ion does not however invalidate any other reasons why the executable *
* file might be covered by the GNU Public License. *
* *
* GNAT was originally developed by the GNAT team at New York University. *
* Extensive contributions were provided by Ada Core Technologies Inc. *
* *
****************************************************************************/
/* This unit contains initialization circuits that are system dependent. A
major part of the functionality involved involves stack overflow checking.
The GCC backend generates probe instructions to test for stack overflow.
For details on the exact approach used to generate these probes, see the
"Using and Porting GCC" manual, in particular the "Stack Checking" section
and the subsection "Specifying How Stack Checking is Done". The handlers
installed by this file are used to handle resulting signals that come
from these probes failing (i.e. touching protected pages) */
/* This file should be kept synchronized with 2sinit.ads, 2sinit.adb,
s-init-ae653-cert.adb and s-init-xi-sparc.adb. All these files implement
the required functionality for different targets. */
/* The following include is here to meet the published VxWorks requirement
that the __vxworks header appear before any other include. */
#ifdef __vxworks
#include "vxWorks.h"
#endif
#ifdef IN_RTS
#include "tconfig.h"
#include "tsystem.h"
#include <sys/stat.h>
/* We don't have libiberty, so us malloc. */
#define xmalloc(S) malloc (S)
#else
#include "config.h"
#include "system.h"
#endif
#include "adaint.h"
#include "raise.h"
extern void __gnat_raise_program_error (const char *, int);
/* Addresses of exception data blocks for predefined exceptions. Tasking_Error
is not used in this unit, and the abort signal is only used on IRIX. */
extern struct Exception_Data constraint_error;
extern struct Exception_Data numeric_error;
extern struct Exception_Data program_error;
extern struct Exception_Data storage_error;
/* For the Cert run time we use the regular raise exception routine because
Raise_From_Signal_Handler is not available. */
#ifdef CERT
#define Raise_From_Signal_Handler \
__gnat_raise_exception
extern void Raise_From_Signal_Handler (struct Exception_Data *, const char *);
#else
#define Raise_From_Signal_Handler \
ada__exceptions__raise_from_signal_handler
extern void Raise_From_Signal_Handler (struct Exception_Data *, const char *);
#endif
/* Global values computed by the binder */
int __gl_main_priority = -1;
int __gl_time_slice_val = -1;
char __gl_wc_encoding = 'n';
char __gl_locking_policy = ' ';
char __gl_queuing_policy = ' ';
char __gl_task_dispatching_policy = ' ';
char *__gl_priority_specific_dispatching = 0;
int __gl_num_specific_dispatching = 0;
char *__gl_interrupt_states = 0;
int __gl_num_interrupt_states = 0;
int __gl_unreserve_all_interrupts = 0;
int __gl_exception_tracebacks = 0;
int __gl_zero_cost_exceptions = 0;
int __gl_detect_blocking = 0;
int __gl_default_stack_size = -1;
/* Indication of whether synchronous signal handler has already been
installed by a previous call to adainit */
int __gnat_handler_installed = 0;
#ifndef IN_RTS
int __gnat_inside_elab_final_code = 0;
/* ??? This variable is obsolete since 2001-08-29 but is kept to allow
bootstrap from old GNAT versions (< 3.15). */
#endif
/* HAVE_GNAT_INIT_FLOAT must be set on every targets where a __gnat_init_float
is defined. If this is not set them a void implementation will be defined
at the end of this unit. */
#undef HAVE_GNAT_INIT_FLOAT
/******************************/
/* __gnat_get_interrupt_state */
/******************************/
char __gnat_get_interrupt_state (int);
/* This routine is called from the runtime as needed to determine the state
of an interrupt, as set by an Interrupt_State pragma appearing anywhere
in the current partition. The input argument is the interrupt number,
and the result is one of the following:
'n' this interrupt not set by any Interrupt_State pragma
'u' Interrupt_State pragma set state to User
'r' Interrupt_State pragma set state to Runtime
's' Interrupt_State pragma set state to System */
char
__gnat_get_interrupt_state (int intrup)
{
if (intrup >= __gl_num_interrupt_states)
return 'n';
else
return __gl_interrupt_states [intrup];
}
/***********************************/
/* __gnat_get_specific_dispatching */
/***********************************/
char __gnat_get_specific_dispatching (int);
/* This routine is called from the run time as needed to determine the
priority specific dispatching policy, as set by a
Priority_Specific_Dispatching pragma appearing anywhere in the current
partition. The input argument is the priority number, and the result is
the upper case first character of the policy name, e.g. 'F' for
FIFO_Within_Priorities. A space ' ' is returned if no
Priority_Specific_Dispatching pragma is used in the partition. */
char
__gnat_get_specific_dispatching (int priority)
{
if (__gl_num_specific_dispatching == 0)
return ' ';
else if (priority >= __gl_num_specific_dispatching)
return 'F';
else
return __gl_priority_specific_dispatching [priority];
}
#ifndef IN_RTS
/**********************/
/* __gnat_set_globals */
/**********************/
/* This routine is kept for boostrapping purposes, since the binder generated
file now sets the __gl_* variables directly. */
void
__gnat_set_globals ()
{
}
#endif
/* Notes on the Zero Cost Exceptions scheme and its impact on the signal
handlers implemented below :
What we call Zero Cost Exceptions is implemented using the GCC eh
circuitry, even if the underlying implementation is setjmp/longjmp
based. In any case ...
The GCC unwinder expects to be dealing with call return addresses, since
this is the "nominal" case of what we retrieve while unwinding a regular
call chain. To evaluate if a handler applies at some point in this chain,
the propagation engine needs to determine what region the corresponding
call instruction pertains to. The return address may not be attached to the
same region as the call, so the unwinder unconditionally subtracts "some"
amount to the return addresses it gets to search the region tables. The
exact amount is computed to ensure that the resulting address is inside the
call instruction, and is thus target dependent (think about delay slots for
instance).
When we raise an exception from a signal handler, e.g. to transform a
SIGSEGV into Storage_Error, things need to appear as if the signal handler
had been "called" by the instruction which triggered the signal, so that
exception handlers that apply there are considered. What the unwinder will
retrieve as the return address from the signal handler is what it will find
as the faulting instruction address in the corresponding signal context
pushed by the kernel. Leaving this address untouched may loose, because if
the triggering instruction happens to be the very first of a region, the
later adjustments performed by the unwinder would yield an address outside
that region. We need to compensate for those adjustments at some point,
which we used to do in the GCC unwinding fallback macro.
The thread at http://gcc.gnu.org/ml/gcc-patches/2004-05/msg00343.html
describes a couple of issues with the fallback based compensation approach.
First, on some targets the adjustment to apply depends on the triggering
signal, which is not easily accessible from the macro. Besides, other
languages, e.g. Java, deal with this by performing the adjustment in the
signal handler before the raise, so fallback adjustments just break those
front-ends.
We now follow the Java way for most targets, via adjust_context_for_raise
below. */
/***************/
/* AIX Section */
/***************/
#if defined (_AIX)
#include <signal.h>
#include <sys/time.h>
/* Some versions of AIX don't define SA_NODEFER. */
#ifndef SA_NODEFER
#define SA_NODEFER 0
#endif /* SA_NODEFER */
/* Versions of AIX before 4.3 don't have nanosleep but provide
nsleep instead. */
#ifndef _AIXVERSION_430
extern int nanosleep (struct timestruc_t *, struct timestruc_t *);
int
nanosleep (struct timestruc_t *Rqtp, struct timestruc_t *Rmtp)
{
return nsleep (Rqtp, Rmtp);
}
#endif /* _AIXVERSION_430 */
static void __gnat_error_handler (int);
static void
__gnat_error_handler (int sig)
{
struct Exception_Data *exception;
const char *msg;
switch (sig)
{
case SIGSEGV:
/* FIXME: we need to detect the case of a *real* SIGSEGV */
exception = &storage_error;
msg = "stack overflow or erroneous memory access";
break;
case SIGBUS:
exception = &constraint_error;
msg = "SIGBUS";
break;
case SIGFPE:
exception = &constraint_error;
msg = "SIGFPE";
break;
default:
exception = &program_error;
msg = "unhandled signal";
}
Raise_From_Signal_Handler (exception, msg);
}
void
__gnat_install_handler (void)
{
struct sigaction act;
/* Set up signal handler to map synchronous signals to appropriate
exceptions. Make sure that the handler isn't interrupted by another
signal that might cause a scheduling event! */
act.sa_handler = __gnat_error_handler;
act.sa_flags = SA_NODEFER | SA_RESTART;
sigemptyset (&act.sa_mask);
/* Do not install handlers if interrupt state is "System" */
if (__gnat_get_interrupt_state (SIGABRT) != 's')
sigaction (SIGABRT, &act, NULL);
if (__gnat_get_interrupt_state (SIGFPE) != 's')
sigaction (SIGFPE, &act, NULL);
if (__gnat_get_interrupt_state (SIGILL) != 's')
sigaction (SIGILL, &act, NULL);
if (__gnat_get_interrupt_state (SIGSEGV) != 's')
sigaction (SIGSEGV, &act, NULL);
if (__gnat_get_interrupt_state (SIGBUS) != 's')
sigaction (SIGBUS, &act, NULL);
__gnat_handler_installed = 1;
}
/*****************/
/* Tru64 section */
/*****************/
#elif defined(__alpha__) && defined(__osf__)
#include <signal.h>
#include <sys/siginfo.h>
static void __gnat_error_handler (int, siginfo_t *, struct sigcontext *);
extern char *__gnat_get_code_loc (struct sigcontext *);
extern void __gnat_set_code_loc (struct sigcontext *, char *);
extern size_t __gnat_machine_state_length (void);
static void
__gnat_error_handler
(int sig, siginfo_t *sip, struct sigcontext *context ATTRIBUTE_UNUSED)
{
struct Exception_Data *exception;
static int recurse = 0;
const char *msg;
/* If this was an explicit signal from a "kill", just resignal it. */
if (SI_FROMUSER (sip))
{
signal (sig, SIG_DFL);
kill (getpid(), sig);
}
/* Otherwise, treat it as something we handle. */
switch (sig)
{
case SIGSEGV:
/* If the problem was permissions, this is a constraint error.
Likewise if the failing address isn't maximally aligned or if
we've recursed.
??? Using a static variable here isn't task-safe, but it's
much too hard to do anything else and we're just determining
which exception to raise. */
if (sip->si_code == SEGV_ACCERR
|| (((long) sip->si_addr) & 3) != 0
|| recurse)
{
exception = &constraint_error;
msg = "SIGSEGV";
}
else
{
/* See if the page before the faulting page is accessible. Do that
by trying to access it. We'd like to simply try to access
4096 + the faulting address, but it's not guaranteed to be
the actual address, just to be on the same page. */
recurse++;
((volatile char *)
((long) sip->si_addr & - getpagesize ()))[getpagesize ()];
msg = "stack overflow (or erroneous memory access)";
exception = &storage_error;
}
break;
case SIGBUS:
exception = &program_error;
msg = "SIGBUS";
break;
case SIGFPE:
exception = &constraint_error;
msg = "SIGFPE";
break;
default:
exception = &program_error;
msg = "unhandled signal";
}
recurse = 0;
Raise_From_Signal_Handler (exception, (char *) msg);
}
void
__gnat_install_handler (void)
{
struct sigaction act;
/* Setup signal handler to map synchronous signals to appropriate
exceptions. Make sure that the handler isn't interrupted by another
signal that might cause a scheduling event! */
act.sa_handler = (void (*) (int)) __gnat_error_handler;
act.sa_flags = SA_RESTART | SA_NODEFER | SA_SIGINFO;
sigemptyset (&act.sa_mask);
/* Do not install handlers if interrupt state is "System" */
if (__gnat_get_interrupt_state (SIGABRT) != 's')
sigaction (SIGABRT, &act, NULL);
if (__gnat_get_interrupt_state (SIGFPE) != 's')
sigaction (SIGFPE, &act, NULL);
if (__gnat_get_interrupt_state (SIGILL) != 's')
sigaction (SIGILL, &act, NULL);
if (__gnat_get_interrupt_state (SIGSEGV) != 's')
sigaction (SIGSEGV, &act, NULL);
if (__gnat_get_interrupt_state (SIGBUS) != 's')
sigaction (SIGBUS, &act, NULL);
__gnat_handler_installed = 1;
}
/* Routines called by s-mastop-tru64.adb. */
#define SC_GP 29
char *
__gnat_get_code_loc (struct sigcontext *context)
{
return (char *) context->sc_pc;
}
void
__gnat_set_code_loc (struct sigcontext *context, char *pc)
{
context->sc_pc = (long) pc;
}
size_t
__gnat_machine_state_length (void)
{
return sizeof (struct sigcontext);
}
/*****************/
/* HP-UX section */
/*****************/
#elif defined (__hpux__)
#include <signal.h>
#include <sys/ucontext.h>
static void
__gnat_error_handler (int sig, siginfo_t *siginfo, void *ucontext);
#if defined (__hppa__)
/* __gnat_adjust_context_for_raise - see comments along with the default
version later in this file. */
#define HAVE_GNAT_ADJUST_CONTEXT_FOR_RAISE
void
__gnat_adjust_context_for_raise (int signo ATTRIBUTE_UNUSED, void *ucontext)
{
mcontext_t *mcontext = &((ucontext_t *) ucontext)->uc_mcontext;
if (UseWideRegs (mcontext))
mcontext->ss_wide.ss_32.ss_pcoq_head_lo ++;
else
mcontext->ss_narrow.ss_pcoq_head ++;
}
#endif
static void
__gnat_error_handler
(int sig, siginfo_t *siginfo ATTRIBUTE_UNUSED, void *ucontext)
{
struct Exception_Data *exception;
const char *msg;
switch (sig)
{
case SIGSEGV:
/* FIXME: we need to detect the case of a *real* SIGSEGV */
exception = &storage_error;
msg = "stack overflow or erroneous memory access";
break;
case SIGBUS:
exception = &constraint_error;
msg = "SIGBUS";
break;
case SIGFPE:
exception = &constraint_error;
msg = "SIGFPE";
break;
default:
exception = &program_error;
msg = "unhandled signal";
}
__gnat_adjust_context_for_raise (sig, ucontext);
Raise_From_Signal_Handler (exception, msg);
}
void
__gnat_install_handler (void)
{
struct sigaction act;
/* Set up signal handler to map synchronous signals to appropriate
exceptions. Make sure that the handler isn't interrupted by another
signal that might cause a scheduling event! Also setup an alternate
stack region for the handler execution so that stack overflows can be
handled properly, avoiding a SEGV generation from stack usage by the
handler itself. */
static char handler_stack[SIGSTKSZ*2];
/* SIGSTKSZ appeared to be "short" for the needs in some contexts
(e.g. experiments with GCC ZCX exceptions). */
stack_t stack;
stack.ss_sp = handler_stack;
stack.ss_size = sizeof (handler_stack);
stack.ss_flags = 0;
sigaltstack (&stack, NULL);
act.sa_sigaction = __gnat_error_handler;
act.sa_flags = SA_NODEFER | SA_RESTART | SA_ONSTACK | SA_SIGINFO;
sigemptyset (&act.sa_mask);
/* Do not install handlers if interrupt state is "System" */
if (__gnat_get_interrupt_state (SIGABRT) != 's')
sigaction (SIGABRT, &act, NULL);
if (__gnat_get_interrupt_state (SIGFPE) != 's')
sigaction (SIGFPE, &act, NULL);
if (__gnat_get_interrupt_state (SIGILL) != 's')
sigaction (SIGILL, &act, NULL);
if (__gnat_get_interrupt_state (SIGSEGV) != 's')
sigaction (SIGSEGV, &act, NULL);
if (__gnat_get_interrupt_state (SIGBUS) != 's')
sigaction (SIGBUS, &act, NULL);
__gnat_handler_installed = 1;
}
/*********************/
/* GNU/Linux Section */
/*********************/
#elif defined (linux) && (defined (i386) || defined (__x86_64__) \
|| defined (__ia64__))
#include <signal.h>
#define __USE_GNU 1 /* required to get REG_EIP/RIP from glibc's ucontext.h */
#include <sys/ucontext.h>
/* GNU/Linux, which uses glibc, does not define NULL in included
header files */
#if !defined (NULL)
#define NULL ((void *) 0)
#endif
#if defined (MaRTE)
/* MaRTE OS provides its own version of sigaction, sigfillset, and
sigemptyset (overriding these symbol names). We want to make sure that
the versions provided by the underlying C library are used here (these
versions are renamed by MaRTE to linux_sigaction, fake_linux_sigfillset,
and fake_linux_sigemptyset, respectively). The MaRTE library will not
always be present (it will not be linked if no tasking constructs are
used), so we use the weak symbol mechanism to point always to the symbols
defined within the C library. */
#pragma weak linux_sigaction
int linux_sigaction (int signum, const struct sigaction *act,
struct sigaction *oldact) {
return sigaction (signum, act, oldact);
}
#define sigaction(signum, act, oldact) linux_sigaction (signum, act, oldact)
#pragma weak fake_linux_sigfillset
void fake_linux_sigfillset (sigset_t *set) {
sigfillset (set);
}
#define sigfillset(set) fake_linux_sigfillset (set)
#pragma weak fake_linux_sigemptyset
void fake_linux_sigemptyset (sigset_t *set) {
sigemptyset (set);
}
#define sigemptyset(set) fake_linux_sigemptyset (set)
#endif
static void __gnat_error_handler (int, siginfo_t *siginfo, void *ucontext);
/* __gnat_adjust_context_for_raise - see comments along with the default
version later in this file. */
#define HAVE_GNAT_ADJUST_CONTEXT_FOR_RAISE
void
__gnat_adjust_context_for_raise (int signo ATTRIBUTE_UNUSED, void *ucontext)
{
mcontext_t *mcontext = &((ucontext_t *) ucontext)->uc_mcontext;
#if defined (i386)
mcontext->gregs[REG_EIP]++;
#elif defined (__x86_64__)
mcontext->gregs[REG_RIP]++;
#elif defined (__ia64__)
mcontext->sc_ip++;
#endif
}
static void
__gnat_error_handler (int sig,
siginfo_t *siginfo ATTRIBUTE_UNUSED,
void *ucontext)
{
struct Exception_Data *exception;
const char *msg;
static int recurse = 0;
switch (sig)
{
case SIGSEGV:
/* If the problem was permissions, this is a constraint error.
Likewise if the failing address isn't maximally aligned or if
we've recursed.
??? Using a static variable here isn't task-safe, but it's
much too hard to do anything else and we're just determining
which exception to raise. */
if (recurse)
{
exception = &constraint_error;
msg = "SIGSEGV";
}
else
{
/* Here we would like a discrimination test to see whether the
page before the faulting address is accessible. Unfortunately
Linux seems to have no way of giving us the faulting address.
In versions of a-init.c before 1.95, we had a test of the page
before the stack pointer using:
recurse++;
((volatile char *)
((long) info->esp_at_signal & - getpagesize ()))[getpagesize ()];
but that's wrong, since it tests the stack pointer location, and
the current stack probe code does not move the stack pointer
until all probes succeed.
For now we simply do not attempt any discrimination at all. Note
that this is quite acceptable, since a "real" SIGSEGV can only
occur as the result of an erroneous program */
msg = "stack overflow (or erroneous memory access)";
exception = &storage_error;
}
break;
case SIGBUS:
exception = &constraint_error;
msg = "SIGBUS";
break;
case SIGFPE:
exception = &constraint_error;
msg = "SIGFPE";
break;
default:
exception = &program_error;
msg = "unhandled signal";
}
recurse = 0;
/* We adjust the interrupted context here (and not in the
MD_FALLBACK_FRAME_STATE_FOR macro) because recent versions of the Native
POSIX Thread Library (NPTL) are compiled with DWARF 2 unwind information,
and hence the later macro is never executed for signal frames. */
__gnat_adjust_context_for_raise (sig, ucontext);
Raise_From_Signal_Handler (exception, msg);
}
void
__gnat_install_handler (void)
{
struct sigaction act;
/* Set up signal handler to map synchronous signals to appropriate
exceptions. Make sure that the handler isn't interrupted by another
signal that might cause a scheduling event! */
act.sa_sigaction = __gnat_error_handler;
act.sa_flags = SA_NODEFER | SA_RESTART | SA_SIGINFO;
sigemptyset (&act.sa_mask);
/* Do not install handlers if interrupt state is "System" */
if (__gnat_get_interrupt_state (SIGABRT) != 's')
sigaction (SIGABRT, &act, NULL);
if (__gnat_get_interrupt_state (SIGFPE) != 's')
sigaction (SIGFPE, &act, NULL);
if (__gnat_get_interrupt_state (SIGILL) != 's')
sigaction (SIGILL, &act, NULL);
if (__gnat_get_interrupt_state (SIGSEGV) != 's')
sigaction (SIGSEGV, &act, NULL);
if (__gnat_get_interrupt_state (SIGBUS) != 's')
sigaction (SIGBUS, &act, NULL);
__gnat_handler_installed = 1;
}
/*******************/
/* Interix Section */
/*******************/
#elif defined (__INTERIX)
#include <signal.h>
static void __gnat_error_handler (int);
static void
__gnat_error_handler (int sig)
{
struct Exception_Data *exception;
const char *msg;
switch (sig)
{
case SIGSEGV:
exception = &storage_error;
msg = "stack overflow or erroneous memory access";
break;
case SIGBUS:
exception = &constraint_error;
msg = "SIGBUS";
break;
case SIGFPE:
exception = &constraint_error;
msg = "SIGFPE";
break;
default:
exception = &program_error;
msg = "unhandled signal";
}
Raise_From_Signal_Handler (exception, msg);
}
void
__gnat_install_handler (void)
{
struct sigaction act;
/* Set up signal handler to map synchronous signals to appropriate
exceptions. Make sure that the handler isn't interrupted by another
signal that might cause a scheduling event! */
act.sa_handler = __gnat_error_handler;
act.sa_flags = 0;
sigemptyset (&act.sa_mask);
/* Handlers for signals besides SIGSEGV cause c974013 to hang */
/* sigaction (SIGILL, &act, NULL); */
/* sigaction (SIGABRT, &act, NULL); */
/* sigaction (SIGFPE, &act, NULL); */
/* sigaction (SIGBUS, &act, NULL); */
/* Do not install handlers if interrupt state is "System" */
if (__gnat_get_interrupt_state (SIGSEGV) != 's')
sigaction (SIGSEGV, &act, NULL);
__gnat_handler_installed = 1;
}
/****************/
/* IRIX Section */
/****************/
#elif defined (sgi)
#include <signal.h>
#include <siginfo.h>
#ifndef NULL
#define NULL 0
#endif
#define SIGADAABORT 48
#define SIGNAL_STACK_SIZE 4096
#define SIGNAL_STACK_ALIGNMENT 64
#define Check_Abort_Status \
system__soft_links__check_abort_status
extern int (*Check_Abort_Status) (void);
extern struct Exception_Data _abort_signal;
static void __gnat_error_handler (int, int, sigcontext_t *);
/* We are not setting the SA_SIGINFO bit in the sigaction flags when
connecting that handler, with the effects described in the sigaction
man page:
SA_SIGINFO [...]
If cleared and the signal is caught, the first argument is
also the signal number but the second argument is the signal
code identifying the cause of the signal. The third argument
points to a sigcontext_t structure containing the receiving
process's context when the signal was delivered.
*/
static void
__gnat_error_handler (int sig, int code, sigcontext_t *sc ATTRIBUTE_UNUSED)
{
struct Exception_Data *exception;
const char *msg;
switch (sig)
{
case SIGSEGV:
if (code == EFAULT)
{
exception = &program_error;
msg = "SIGSEGV: (Invalid virtual address)";
}
else if (code == ENXIO)
{
exception = &program_error;
msg = "SIGSEGV: (Read beyond mapped object)";
}
else if (code == ENOSPC)
{
exception = &program_error; /* ??? storage_error ??? */
msg = "SIGSEGV: (Autogrow for file failed)";
}
else if (code == EACCES || code == EEXIST)
{
/* ??? We handle stack overflows here, some of which do trigger
SIGSEGV + EEXIST on Irix 6.5 although EEXIST is not part of
the documented valid codes for SEGV in the signal(5) man
page. */
/* ??? Re-add smarts to further verify that we launched
the stack into a guard page, not an attempt to
write to .text or something */
exception = &storage_error;
msg = "SIGSEGV: (stack overflow or erroneous memory access)";
}
else
{
/* Just in case the OS guys did it to us again. Sometimes
they fail to document all of the valid codes that are
passed to signal handlers, just in case someone depends
on knowing all the codes */
exception = &program_error;
msg = "SIGSEGV: (Undocumented reason)";
}
break;
case SIGBUS:
/* Map all bus errors to Program_Error. */
exception = &program_error;
msg = "SIGBUS";
break;
case SIGFPE:
/* Map all fpe errors to Constraint_Error. */
exception = &constraint_error;
msg = "SIGFPE";
break;
case SIGADAABORT:
if ((*Check_Abort_Status) ())
{
exception = &_abort_signal;
msg = "";
}
else
return;
break;
default:
/* Everything else is a Program_Error. */
exception = &program_error;
msg = "unhandled signal";
}
Raise_From_Signal_Handler (exception, msg);
}
void
__gnat_install_handler (void)
{
struct sigaction act;
/* Setup signal handler to map synchronous signals to appropriate
exceptions. Make sure that the handler isn't interrupted by another
signal that might cause a scheduling event! */
act.sa_handler = __gnat_error_handler;
act.sa_flags = SA_NODEFER + SA_RESTART;
sigfillset (&act.sa_mask);
sigemptyset (&act.sa_mask);
/* Do not install handlers if interrupt state is "System" */
if (__gnat_get_interrupt_state (SIGABRT) != 's')
sigaction (SIGABRT, &act, NULL);
if (__gnat_get_interrupt_state (SIGFPE) != 's')
sigaction (SIGFPE, &act, NULL);
if (__gnat_get_interrupt_state (SIGILL) != 's')
sigaction (SIGILL, &act, NULL);
if (__gnat_get_interrupt_state (SIGSEGV) != 's')
sigaction (SIGSEGV, &act, NULL);
if (__gnat_get_interrupt_state (SIGBUS) != 's')
sigaction (SIGBUS, &act, NULL);
if (__gnat_get_interrupt_state (SIGADAABORT) != 's')
sigaction (SIGADAABORT, &act, NULL);
__gnat_handler_installed = 1;
}
/*******************/
/* Solaris Section */
/*******************/
#elif defined (sun) && defined (__SVR4) && !defined (__vxworks)
#include <signal.h>
#include <siginfo.h>
static void __gnat_error_handler (int, siginfo_t *);
static void
__gnat_error_handler (int sig, siginfo_t *sip)
{
struct Exception_Data *exception;
static int recurse = 0;
const char *msg;
/* If this was an explicit signal from a "kill", just resignal it. */
if (SI_FROMUSER (sip))
{
signal (sig, SIG_DFL);
kill (getpid(), sig);
}
/* Otherwise, treat it as something we handle. */
switch (sig)
{
case SIGSEGV:
/* If the problem was permissions, this is a constraint error.
Likewise if the failing address isn't maximally aligned or if
we've recursed.
??? Using a static variable here isn't task-safe, but it's
much too hard to do anything else and we're just determining
which exception to raise. */
if (sip->si_code == SEGV_ACCERR
|| (((long) sip->si_addr) & 3) != 0
|| recurse)
{
exception = &constraint_error;
msg = "SIGSEGV";
}
else
{
/* See if the page before the faulting page is accessible. Do that
by trying to access it. We'd like to simply try to access
4096 + the faulting address, but it's not guaranteed to be
the actual address, just to be on the same page. */
recurse++;
((volatile char *)
((long) sip->si_addr & - getpagesize ()))[getpagesize ()];
exception = &storage_error;
msg = "stack overflow (or erroneous memory access)";
}
break;
case SIGBUS:
exception = &program_error;
msg = "SIGBUS";
break;
case SIGFPE:
exception = &constraint_error;
msg = "SIGFPE";
break;
default:
exception = &program_error;
msg = "unhandled signal";
}
recurse = 0;
Raise_From_Signal_Handler (exception, msg);
}
void
__gnat_install_handler (void)
{
struct sigaction act;
/* Set up signal handler to map synchronous signals to appropriate
exceptions. Make sure that the handler isn't interrupted by another
signal that might cause a scheduling event! */
act.sa_handler = __gnat_error_handler;
act.sa_flags = SA_NODEFER | SA_RESTART | SA_SIGINFO;
sigemptyset (&act.sa_mask);
/* Do not install handlers if interrupt state is "System" */
if (__gnat_get_interrupt_state (SIGABRT) != 's')
sigaction (SIGABRT, &act, NULL);
if (__gnat_get_interrupt_state (SIGFPE) != 's')
sigaction (SIGFPE, &act, NULL);
if (__gnat_get_interrupt_state (SIGSEGV) != 's')
sigaction (SIGSEGV, &act, NULL);
if (__gnat_get_interrupt_state (SIGBUS) != 's')
sigaction (SIGBUS, &act, NULL);
__gnat_handler_installed = 1;
}
/***************/
/* VMS Section */
/***************/
#elif defined (VMS)
long __gnat_error_handler (int *, void *);
#ifdef __IA64
#define lib_get_curr_invo_context LIB$I64_GET_CURR_INVO_CONTEXT
#define lib_get_prev_invo_context LIB$I64_GET_PREV_INVO_CONTEXT
#define lib_get_invo_handle LIB$I64_GET_INVO_HANDLE
#else
#define lib_get_curr_invo_context LIB$GET_CURR_INVO_CONTEXT
#define lib_get_prev_invo_context LIB$GET_PREV_INVO_CONTEXT
#define lib_get_invo_handle LIB$GET_INVO_HANDLE
#endif
#if defined (IN_RTS) && !defined (__IA64)
/* The prehandler actually gets control first on a condition. It swaps the
stack pointer and calls the handler (__gnat_error_handler). */
extern long __gnat_error_prehandler (void);
extern char *__gnat_error_prehandler_stack; /* Alternate signal stack */
#endif
/* Define macro symbols for the VMS conditions that become Ada exceptions.
Most of these are also defined in the header file ssdef.h which has not
yet been converted to be recognized by Gnu C. */
/* Defining these as macros, as opposed to external addresses, allows
them to be used in a case statement (below */
#define SS$_ACCVIO 12
#define SS$_HPARITH 1284
#define SS$_STKOVF 1364
#define SS$_RESIGNAL 2328
/* These codes are in standard message libraries */
extern int CMA$_EXIT_THREAD;
extern int SS$_DEBUG;
extern int SS$_INTDIV;
extern int LIB$_KEYNOTFOU;
extern int LIB$_ACTIMAGE;
extern int MTH$_FLOOVEMAT; /* Some ACVC_21 CXA tests */
/* These codes are non standard, which is to say the author is
not sure if they are defined in the standard message libraries
so keep them as macros for now. */
#define RDB$_STREAM_EOF 20480426
#define FDL$_UNPRIKW 11829410
struct cond_except {
const int *cond;
const struct Exception_Data *except;
};
struct descriptor_s {unsigned short len, mbz; __char_ptr32 adr; };
/* Conditions that don't have an Ada exception counterpart must raise
Non_Ada_Error. Since this is defined in s-auxdec, it should only be
referenced by user programs, not the compiler or tools. Hence the
#ifdef IN_RTS. */
#ifdef IN_RTS
#define Status_Error ada__io_exceptions__status_error
extern struct Exception_Data Status_Error;
#define Mode_Error ada__io_exceptions__mode_error
extern struct Exception_Data Mode_Error;
#define Name_Error ada__io_exceptions__name_error
extern struct Exception_Data Name_Error;
#define Use_Error ada__io_exceptions__use_error
extern struct Exception_Data Use_Error;
#define Device_Error ada__io_exceptions__device_error
extern struct Exception_Data Device_Error;
#define End_Error ada__io_exceptions__end_error
extern struct Exception_Data End_Error;
#define Data_Error ada__io_exceptions__data_error
extern struct Exception_Data Data_Error;
#define Layout_Error ada__io_exceptions__layout_error
extern struct Exception_Data Layout_Error;
#define Non_Ada_Error system__aux_dec__non_ada_error
extern struct Exception_Data Non_Ada_Error;
#define Coded_Exception system__vms_exception_table__coded_exception
extern struct Exception_Data *Coded_Exception (Exception_Code);
#define Base_Code_In system__vms_exception_table__base_code_in
extern Exception_Code Base_Code_In (Exception_Code);
/* DEC Ada exceptions are not defined in a header file, so they
must be declared as external addresses */
extern int ADA$_PROGRAM_ERROR;
extern int ADA$_LOCK_ERROR;
extern int ADA$_EXISTENCE_ERROR;
extern int ADA$_KEY_ERROR;
extern int ADA$_KEYSIZERR;
extern int ADA$_STAOVF;
extern int ADA$_CONSTRAINT_ERRO;
extern int ADA$_IOSYSFAILED;
extern int ADA$_LAYOUT_ERROR;
extern int ADA$_STORAGE_ERROR;
extern int ADA$_DATA_ERROR;
extern int ADA$_DEVICE_ERROR;
extern int ADA$_END_ERROR;
extern int ADA$_MODE_ERROR;
extern int ADA$_NAME_ERROR;
extern int ADA$_STATUS_ERROR;
extern int ADA$_NOT_OPEN;
extern int ADA$_ALREADY_OPEN;
extern int ADA$_USE_ERROR;
extern int ADA$_UNSUPPORTED;
extern int ADA$_FAC_MODE_MISMAT;
extern int ADA$_ORG_MISMATCH;
extern int ADA$_RFM_MISMATCH;
extern int ADA$_RAT_MISMATCH;
extern int ADA$_MRS_MISMATCH;
extern int ADA$_MRN_MISMATCH;
extern int ADA$_KEY_MISMATCH;
extern int ADA$_MAXLINEXC;
extern int ADA$_LINEXCMRS;
/* DEC Ada specific conditions */
static const struct cond_except dec_ada_cond_except_table [] = {
{&ADA$_PROGRAM_ERROR, &program_error},
{&ADA$_USE_ERROR, &Use_Error},
{&ADA$_KEYSIZERR, &program_error},
{&ADA$_STAOVF, &storage_error},
{&ADA$_CONSTRAINT_ERRO, &constraint_error},
{&ADA$_IOSYSFAILED, &Device_Error},
{&ADA$_LAYOUT_ERROR, &Layout_Error},
{&ADA$_STORAGE_ERROR, &storage_error},
{&ADA$_DATA_ERROR, &Data_Error},
{&ADA$_DEVICE_ERROR, &Device_Error},
{&ADA$_END_ERROR, &End_Error},
{&ADA$_MODE_ERROR, &Mode_Error},
{&ADA$_NAME_ERROR, &Name_Error},
{&ADA$_STATUS_ERROR, &Status_Error},
{&ADA$_NOT_OPEN, &Use_Error},
{&ADA$_ALREADY_OPEN, &Use_Error},
{&ADA$_USE_ERROR, &Use_Error},
{&ADA$_UNSUPPORTED, &Use_Error},
{&ADA$_FAC_MODE_MISMAT, &Use_Error},
{&ADA$_ORG_MISMATCH, &Use_Error},
{&ADA$_RFM_MISMATCH, &Use_Error},
{&ADA$_RAT_MISMATCH, &Use_Error},
{&ADA$_MRS_MISMATCH, &Use_Error},
{&ADA$_MRN_MISMATCH, &Use_Error},
{&ADA$_KEY_MISMATCH, &Use_Error},
{&ADA$_MAXLINEXC, &constraint_error},
{&ADA$_LINEXCMRS, &constraint_error},
{0, 0}
};
#if 0
/* Already handled by a pragma Import_Exception
in Aux_IO_Exceptions */
{&ADA$_LOCK_ERROR, &Lock_Error},
{&ADA$_EXISTENCE_ERROR, &Existence_Error},
{&ADA$_KEY_ERROR, &Key_Error},
#endif
#endif /* IN_RTS */
/* Non DEC Ada specific conditions. We could probably also put
SS$_HPARITH here and possibly SS$_ACCVIO, SS$_STKOVF. */
static const struct cond_except cond_except_table [] = {
{&MTH$_FLOOVEMAT, &constraint_error},
{&SS$_INTDIV, &constraint_error},
{0, 0}
};
/* To deal with VMS conditions and their mapping to Ada exceptions,
the __gnat_error_handler routine below is installed as an exception
vector having precedence over DEC frame handlers. Some conditions
still need to be handled by such handlers, however, in which case
__gnat_error_handler needs to return SS$_RESIGNAL. Consider for
instance the use of a third party library compiled with DECAda and
performing it's own exception handling internally.
To allow some user-level flexibility, which conditions should be
resignaled is controlled by a predicate function, provided with the
condition value and returning a boolean indication stating whether
this condition should be resignaled or not.
That predicate function is called indirectly, via a function pointer,
by __gnat_error_handler, and changing that pointer is allowed to the
the user code by way of the __gnat_set_resignal_predicate interface.
The user level function may then implement what it likes, including
for instance the maintenance of a dynamic data structure if the set
of to be resignalled conditions has to change over the program's
lifetime.
??? This is not a perfect solution to deal with the possible
interactions between the GNAT and the DECAda exception handling
models and better (more general) schemes are studied. This is so
just provided as a convenient workaround in the meantime, and
should be use with caution since the implementation has been kept
very simple. */
typedef int
resignal_predicate (int code);
const int *cond_resignal_table [] = {
&CMA$_EXIT_THREAD,
&SS$_DEBUG,
&LIB$_KEYNOTFOU,
&LIB$_ACTIMAGE,
(int *) RDB$_STREAM_EOF,
(int *) FDL$_UNPRIKW,
0
};
const int facility_resignal_table [] = {
0x1380000, /* RDB */
0x2220000, /* SQL */
0
};
/* Default GNAT predicate for resignaling conditions. */
static int
__gnat_default_resignal_p (int code)
{
int i, iexcept;
for (i = 0; facility_resignal_table [i]; i++)
if ((code & 0xfff0000) == facility_resignal_table [i])
return 1;
for (i = 0, iexcept = 0;
cond_resignal_table [i] &&
!(iexcept = LIB$MATCH_COND (&code, &cond_resignal_table [i]));
i++);
return iexcept;
}
/* Static pointer to predicate that the __gnat_error_handler exception
vector invokes to determine if it should resignal a condition. */
static resignal_predicate * __gnat_resignal_p = __gnat_default_resignal_p;
/* User interface to change the predicate pointer to PREDICATE. Reset to
the default if PREDICATE is null. */
void
__gnat_set_resignal_predicate (resignal_predicate * predicate)
{
if (predicate == 0)
__gnat_resignal_p = __gnat_default_resignal_p;
else
__gnat_resignal_p = predicate;
}
/* Should match System.Parameters.Default_Exception_Msg_Max_Length */
#define Default_Exception_Msg_Max_Length 512
/* Action routine for SYS$PUTMSG. There may be
multiple conditions, each with text to be appended to
MESSAGE and separated by line termination. */
static int
copy_msg (msgdesc, message)
struct descriptor_s *msgdesc;
char *message;
{
int len = strlen (message);
int copy_len;
/* Check for buffer overflow and skip */
if (len > 0 && len <= Default_Exception_Msg_Max_Length - 3)
{
strcat (message, "\r\n");
len += 2;
}
/* Check for buffer overflow and truncate if necessary */
copy_len = (len + msgdesc->len <= Default_Exception_Msg_Max_Length - 1 ?
msgdesc->len :
Default_Exception_Msg_Max_Length - 1 - len);
strncpy (&message [len], msgdesc->adr, copy_len);
message [len + copy_len] = 0;
return 0;
}
long
__gnat_handle_vms_condition (int *sigargs, void *mechargs)
{
struct Exception_Data *exception = 0;
Exception_Code base_code;
struct descriptor_s gnat_facility = {4,0,"GNAT"};
char message [Default_Exception_Msg_Max_Length];
const char *msg = "";
/* Check for conditions to resignal which aren't effected by pragma
Import_Exception. */
if (__gnat_resignal_p (sigargs [1]))
return SS$_RESIGNAL;
#ifdef IN_RTS
/* See if it's an imported exception. Beware that registered exceptions
are bound to their base code, with the severity bits masked off. */
base_code = Base_Code_In ((Exception_Code) sigargs [1]);
exception = Coded_Exception (base_code);
if (exception)
{
message [0] = 0;
/* Subtract PC & PSL fields which messes with PUTMSG */
sigargs [0] -= 2;
SYS$PUTMSG (sigargs, copy_msg, &gnat_facility, message);
sigargs [0] += 2;
msg = message;
exception->Name_Length = 19;
/* The full name really should be get sys$getmsg returns. ??? */
exception->Full_Name = "IMPORTED_EXCEPTION";
exception->Import_Code = base_code;
}
#endif
if (exception == 0)
switch (sigargs[1])
{
case SS$_ACCVIO:
if (sigargs[3] == 0)
{
exception = &constraint_error;
msg = "access zero";
}
else
{
exception = &storage_error;
msg = "stack overflow (or erroneous memory access)";
}
break;
case SS$_STKOVF:
exception = &storage_error;
msg = "stack overflow";
break;
case SS$_HPARITH:
#ifndef IN_RTS
return SS$_RESIGNAL; /* toplev.c handles for compiler */
#else
{
exception = &constraint_error;
msg = "arithmetic error";
}
#endif
break;
default:
#ifdef IN_RTS
{
int i;
/* Scan the DEC Ada exception condition table for a match and fetch
the associated GNAT exception pointer */
for (i = 0;
dec_ada_cond_except_table [i].cond &&
!LIB$MATCH_COND (&sigargs [1],
&dec_ada_cond_except_table [i].cond);
i++);
exception = (struct Exception_Data *)
dec_ada_cond_except_table [i].except;
if (!exception)
{
/* Scan the VMS standard condition table for a match and fetch
the associated GNAT exception pointer */
for (i = 0;
cond_except_table [i].cond &&
!LIB$MATCH_COND (&sigargs [1], &cond_except_table [i].cond);
i++);
exception =(struct Exception_Data *) cond_except_table [i].except;
if (!exception)
/* User programs expect Non_Ada_Error to be raised, reference
DEC Ada test CXCONDHAN. */
exception = &Non_Ada_Error;
}
}
#else
exception = &program_error;
#endif
message [0] = 0;
/* Subtract PC & PSL fields which messes with PUTMSG */
sigargs [0] -= 2;
SYS$PUTMSG (sigargs, copy_msg, &gnat_facility, message);
sigargs [0] += 2;
msg = message;
break;
}
__gnat_adjust_context_for_raise (0, (void *)mechargs);
Raise_From_Signal_Handler (exception, msg);
}
long
__gnat_error_handler (int *sigargs, void *mechargs)
{
return __gnat_handle_vms_condition (sigargs, mechargs);
}
void
__gnat_install_handler (void)
{
long prvhnd ATTRIBUTE_UNUSED;
#if !defined (IN_RTS)
SYS$SETEXV (1, __gnat_error_handler, 3, &prvhnd);
#endif
/* On alpha-vms, we avoid the global vector annoyance thanks to frame based
handlers to turn conditions into exceptions since GCC 3.4. The global
vector is still required for earlier GCC versions. We're resorting to
the __gnat_error_prehandler assembly function in this case. */
#if defined (IN_RTS) && defined (__alpha__)
if ((__GNUC__ * 10 + __GNUC_MINOR__) < 34)
{
char * c = (char *) xmalloc (2049);
__gnat_error_prehandler_stack = &c[2048];
SYS$SETEXV (1, __gnat_error_prehandler, 3, &prvhnd);
}
#endif
__gnat_handler_installed = 1;
}
/* __gnat_adjust_context_for_raise for alpha - see comments along with the
default version later in this file. */
#if defined (IN_RTS) && defined (__alpha__)
#include <vms/chfctxdef.h>
#include <vms/chfdef.h>
#define HAVE_GNAT_ADJUST_CONTEXT_FOR_RAISE
void
__gnat_adjust_context_for_raise (int signo ATTRIBUTE_UNUSED, void *ucontext)
{
/* Add one to the address of the instruction signaling the condition,
located in the sigargs array. */
CHF$MECH_ARRAY * mechargs = (CHF$MECH_ARRAY *) ucontext;
CHF$SIGNAL_ARRAY * sigargs
= (CHF$SIGNAL_ARRAY *) mechargs->chf$q_mch_sig_addr;
int vcount = sigargs->chf$is_sig_args;
int * pc_slot = & (&sigargs->chf$l_sig_name)[vcount-2];
(*pc_slot) ++;
}
#endif
/* __gnat_adjust_context_for_raise for ia64. */
#if defined (IN_RTS) && defined (__IA64)
#include <vms/chfctxdef.h>
#include <vms/chfdef.h>
#define HAVE_GNAT_ADJUST_CONTEXT_FOR_RAISE
typedef unsigned long long u64;
void
__gnat_adjust_context_for_raise (int signo ATTRIBUTE_UNUSED, void *ucontext)
{
/* Add one to the address of the instruction signaling the condition,
located in the 64bits sigargs array. */
CHF$MECH_ARRAY * mechargs = (CHF$MECH_ARRAY *) ucontext;
CHF64$SIGNAL_ARRAY *chfsig64
= (CHF64$SIGNAL_ARRAY *) mechargs->chf$ph_mch_sig64_addr;
u64 * post_sigarray
= (u64 *)chfsig64 + 1 + chfsig64->chf64$l_sig_args;
u64 * ih_pc_loc = post_sigarray - 2;
(*ih_pc_loc) ++;
}
#endif
/*******************/
/* FreeBSD Section */
/*******************/
#elif defined (__FreeBSD__)
#include <signal.h>
#include <sys/ucontext.h>
#include <unistd.h>
static void __gnat_error_handler (int, siginfo_t *, ucontext_t *);
void __gnat_adjust_context_for_raise (int, void*);
/* __gnat_adjust_context_for_raise - see comments along with the default
version later in this file. */
#define HAVE_GNAT_ADJUST_CONTEXT_FOR_RAISE
void
__gnat_adjust_context_for_raise (int signo ATTRIBUTE_UNUSED, void *ucontext)
{
mcontext_t *mcontext = &((ucontext_t *) ucontext)->uc_mcontext;
mcontext->mc_eip++;
}
static void
__gnat_error_handler (int sig, siginfo_t *info __attribute__ ((unused)),
ucontext_t *ucontext)
{
struct Exception_Data *exception;
const char *msg;
switch (sig)
{
case SIGFPE:
exception = &constraint_error;
msg = "SIGFPE";
break;
case SIGILL:
exception = &constraint_error;
msg = "SIGILL";
break;
case SIGSEGV:
exception = &storage_error;
msg = "stack overflow or erroneous memory access";
break;
case SIGBUS:
exception = &constraint_error;
msg = "SIGBUS";
break;
default:
exception = &program_error;
msg = "unhandled signal";
}
__gnat_adjust_context_for_raise (sig, ucontext);
Raise_From_Signal_Handler (exception, msg);
}
void
__gnat_install_handler ()
{
struct sigaction act;
/* Set up signal handler to map synchronous signals to appropriate
exceptions. Make sure that the handler isn't interrupted by another
signal that might cause a scheduling event! */
act.sa_sigaction
= (void (*)(int, struct __siginfo *, void*)) __gnat_error_handler;
act.sa_flags = SA_NODEFER | SA_RESTART | SA_SIGINFO;
(void) sigemptyset (&act.sa_mask);
(void) sigaction (SIGILL, &act, NULL);
(void) sigaction (SIGFPE, &act, NULL);
(void) sigaction (SIGSEGV, &act, NULL);
(void) sigaction (SIGBUS, &act, NULL);
__gnat_handler_installed = 1;
}
/*******************/
/* VxWorks Section */
/*******************/
#elif defined(__vxworks)
#include <signal.h>
#include <taskLib.h>
#ifndef __RTP__
#include <intLib.h>
#include <iv.h>
#endif
#ifdef VTHREADS
#include "private/vThreadsP.h"
#endif
static void __gnat_error_handler (int, int, struct sigcontext *);
void __gnat_map_signal (int);
#ifndef __RTP__
/* Directly vectored Interrupt routines are not supported when using RTPs */
extern int __gnat_inum_to_ivec (int);
/* This is needed by the GNAT run time to handle Vxworks interrupts */
int
__gnat_inum_to_ivec (int num)
{
return INUM_TO_IVEC (num);
}
#endif
#if !defined(__alpha_vxworks) && (_WRS_VXWORKS_MAJOR != 6) && !defined(__RTP__)
/* getpid is used by s-parint.adb, but is not defined by VxWorks, except
on Alpha VxWorks and VxWorks 6.x (including RTPs). */
extern long getpid (void);
long
getpid (void)
{
return taskIdSelf ();
}
#endif
/* VxWorks expects the field excCnt to be zeroed when a signal is handled.
The VxWorks version of longjmp does this; gcc's builtin_longjmp does not */
void
__gnat_clear_exception_count (void)
{
#ifdef VTHREADS
WIND_TCB *currentTask = (WIND_TCB *) taskIdSelf();
currentTask->vThreads.excCnt = 0;
#endif
}
/* Exported to s-intman-vxworks.adb in order to handle different signal
to exception mappings in different VxWorks versions */
void
__gnat_map_signal (int sig)
{
struct Exception_Data *exception;
const char *msg;
switch (sig)
{
case SIGFPE:
exception = &constraint_error;
msg = "SIGFPE";
break;
#ifdef VTHREADS
case SIGILL:
exception = &constraint_error;
msg = "Floating point exception or SIGILL";
break;
case SIGSEGV:
exception = &storage_error;
msg = "SIGSEGV: possible stack overflow";
break;
case SIGBUS:
exception = &storage_error;
msg = "SIGBUS: possible stack overflow";
break;
#else
case SIGILL:
exception = &constraint_error;
msg = "SIGILL";
break;
case SIGSEGV:
exception = &program_error;
msg = "SIGSEGV";
break;
case SIGBUS:
exception = &program_error;
msg = "SIGBUS";
break;
#endif
default:
exception = &program_error;
msg = "unhandled signal";
}
__gnat_clear_exception_count ();
Raise_From_Signal_Handler (exception, msg);
}
static void
__gnat_error_handler (int sig, int code, struct sigcontext *sc)
{
sigset_t mask;
int result;
/* VxWorks will always mask out the signal during the signal handler and
will reenable it on a longjmp. GNAT does not generate a longjmp to
return from a signal handler so the signal will still be masked unless
we unmask it. */
sigprocmask (SIG_SETMASK, NULL, &mask);
sigdelset (&mask, sig);
sigprocmask (SIG_SETMASK, &mask, NULL);
__gnat_map_signal (sig);
}
void
__gnat_install_handler (void)
{
struct sigaction act;
/* Setup signal handler to map synchronous signals to appropriate
exceptions. Make sure that the handler isn't interrupted by another
signal that might cause a scheduling event! */
act.sa_handler = __gnat_error_handler;
act.sa_flags = SA_SIGINFO | SA_ONSTACK;
sigemptyset (&act.sa_mask);
/* For VxWorks, install all signal handlers, since pragma Interrupt_State
applies to vectored hardware interrupts, not signals */
sigaction (SIGFPE, &act, NULL);
sigaction (SIGILL, &act, NULL);
sigaction (SIGSEGV, &act, NULL);
sigaction (SIGBUS, &act, NULL);
__gnat_handler_installed = 1;
}
#define HAVE_GNAT_INIT_FLOAT
void
__gnat_init_float (void)
{
/* Disable overflow/underflow exceptions on the PPC processor, this is needed
to get correct Ada semantics. Note that for AE653 vThreads, the HW
overflow settings are an OS configuration issue. The instructions
below have no effect */
#if defined (_ARCH_PPC) && !defined (_SOFT_FLOAT) && !defined (VTHREADS)
asm ("mtfsb0 25");
asm ("mtfsb0 26");
#endif
#if (defined (__i386__) || defined (i386)) && !defined (VTHREADS)
/* This is used to properly initialize the FPU on an x86 for each
process thread. */
asm ("finit");
#endif
/* Similarly for sparc64. Achieved by masking bits in the Trap Enable Mask
field of the Floating-point Status Register (see the SPARC Architecture
Manual Version 9, p 48). */
#if defined (sparc64)
#define FSR_TEM_NVM (1 << 27) /* Invalid operand */
#define FSR_TEM_OFM (1 << 26) /* Overflow */
#define FSR_TEM_UFM (1 << 25) /* Underflow */
#define FSR_TEM_DZM (1 << 24) /* Division by Zero */
#define FSR_TEM_NXM (1 << 23) /* Inexact result */
{
unsigned int fsr;
__asm__("st %%fsr, %0" : "=m" (fsr));
fsr &= ~(FSR_TEM_OFM | FSR_TEM_UFM);
__asm__("ld %0, %%fsr" : : "m" (fsr));
}
#endif
}
/******************/
/* NetBSD Section */
/******************/
#elif defined(__NetBSD__)
#include <signal.h>
#include <unistd.h>
static void
__gnat_error_handler (int sig)
{
struct Exception_Data *exception;
const char *msg;
switch(sig)
{
case SIGFPE:
exception = &constraint_error;
msg = "SIGFPE";
break;
case SIGILL:
exception = &constraint_error;
msg = "SIGILL";
break;
case SIGSEGV:
exception = &storage_error;
msg = "stack overflow or erroneous memory access";
break;
case SIGBUS:
exception = &constraint_error;
msg = "SIGBUS";
break;
default:
exception = &program_error;
msg = "unhandled signal";
}
Raise_From_Signal_Handler(exception, msg);
}
void
__gnat_install_handler(void)
{
struct sigaction act;
act.sa_handler = __gnat_error_handler;
act.sa_flags = SA_NODEFER | SA_RESTART;
sigemptyset (&act.sa_mask);
/* Do not install handlers if interrupt state is "System" */
if (__gnat_get_interrupt_state (SIGFPE) != 's')
sigaction (SIGFPE, &act, NULL);
if (__gnat_get_interrupt_state (SIGILL) != 's')
sigaction (SIGILL, &act, NULL);
if (__gnat_get_interrupt_state (SIGSEGV) != 's')
sigaction (SIGSEGV, &act, NULL);
if (__gnat_get_interrupt_state (SIGBUS) != 's')
sigaction (SIGBUS, &act, NULL);
__gnat_handler_installed = 1;
}
#else
/* For all other versions of GNAT, the handler does nothing */
/*******************/
/* Default Section */
/*******************/
void
__gnat_install_handler (void)
{
__gnat_handler_installed = 1;
}
#endif
/*********************/
/* __gnat_init_float */
/*********************/
/* This routine is called as each process thread is created, for possible
initialization of the FP processor. This version is used under INTERIX,
WIN32 and could be used under OS/2 */
#if defined (_WIN32) || defined (__INTERIX) || defined (__EMX__) \
|| defined (__Lynx__) || defined(__NetBSD__) || defined(__FreeBSD__)
#define HAVE_GNAT_INIT_FLOAT
void
__gnat_init_float (void)
{
#if defined (__i386__) || defined (i386)
/* This is used to properly initialize the FPU on an x86 for each
process thread. */
asm ("finit");
#endif /* Defined __i386__ */
}
#endif
#ifndef HAVE_GNAT_INIT_FLOAT
/* All targets without a specific __gnat_init_float will use an empty one */
void
__gnat_init_float (void)
{
}
#endif
/***********************************/
/* __gnat_adjust_context_for_raise */
/***********************************/
#ifndef HAVE_GNAT_ADJUST_CONTEXT_FOR_RAISE
/* All targets without a specific version will use an empty one */
/* UCONTEXT is a pointer to a context structure received by a signal handler
about to propagate an exception. Adjust it to compensate the fact that the
generic unwinder thinks the corresponding PC is a call return address. */
void
__gnat_adjust_context_for_raise (int signo ATTRIBUTE_UNUSED,
void *ucontext ATTRIBUTE_UNUSED)
{
/* The point is that the interrupted context PC typically is the address
that we should search an EH region for, which is different from the call
return address case. The target independent part of the GCC unwinder
don't differentiate the two situations, so we compensate here for the
adjustments it will blindly make.
signo is passed because on some targets for some signals the PC in
context points to the instruction after the faulting one, in which case
the unwinder adjustment is still desired. */
/* On a number of targets, we have arranged for the adjustment to be
performed by the MD_FALLBACK_FRAME_STATE circuitry, so we don't provide a
specific instance of this routine. The MD_FALLBACK doesn't have access
to the signal number, though, so the compensation is systematic there and
might be wrong in some cases. */
/* Having the compensation wrong leads to potential failures. A very
typical case is what happens when there is no compensation and a signal
triggers for the first instruction in a region : the unwinder adjustment
has it search in the wrong EH region. */
}
#endif
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