* *
* C Implementation File *
* *
- * Copyright (C) 1992-2005, Free Software Foundation, Inc. *
+ * Copyright (C) 1992-2009, 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- *
+ * ware Foundation; either version 3, 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. *
+ * or FITNESS FOR A PARTICULAR PURPOSE. *
* *
- * 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. *
+ * As a special exception under Section 7 of GPL version 3, you are granted *
+ * additional permissions described in the GCC Runtime Library Exception, *
+ * version 3.1, as published by the Free Software Foundation. *
+ * *
+ * You should have received a copy of the GNU General Public License and *
+ * a copy of the GCC Runtime Library Exception along with this program; *
+ * see the files COPYING3 and COPYING.RUNTIME respectively. If not, see *
+ * <http://www.gnu.org/licenses/>. *
* *
* 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.
+/* This unit contains initialization circuits that are system dependent.
+ A major part of the functionality 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) */
+ and the subsection "Specifying How Stack Checking is Done". The handlers
+ installed by this file are used to catch the 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. */
+ 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. */
+ that the __vxworks header appear before any other include. */
#ifdef __vxworks
#include "vxWorks.h"
#endif
#include "tsystem.h"
#include <sys/stat.h>
-/* We don't have libiberty, so us malloc. */
+/* We don't have libiberty, so use malloc. */
#define xmalloc(S) malloc (S)
#else
#include "config.h"
extern void __gnat_raise_program_error (const char *, int);
-/* Addresses of exception data blocks for predefined exceptions. */
+/* 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;
-extern struct Exception_Data tasking_error;
-extern struct Exception_Data _abort_signal;
-
-#define Lock_Task system__soft_links__lock_task
-extern void (*Lock_Task) (void);
-
-#define Unlock_Task system__soft_links__unlock_task
-extern void (*Unlock_Task) (void);
-
-#define Check_Abort_Status \
- system__soft_links__check_abort_status
-extern int (*Check_Abort_Status) (void);
+/* 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
-/* Copies of 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_restrictions = 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;
+/* 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;
+int __gl_leap_seconds_support = 0;
+int __gl_canonical_streams = 0;
/* Indication of whether synchronous signal handler has already been
- installed by a previous call to adainit */
+ 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). */
+ 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. */
+ is defined. If this is not set then a void implementation will be defined
+ at the end of this unit. */
#undef HAVE_GNAT_INIT_FLOAT
/******************************/
/* 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,
+ 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 */
+ 's' Interrupt_State pragma set state to System */
char
__gnat_get_interrupt_state (int intrup)
return __gl_interrupt_states [intrup];
}
-/**********************/
-/* __gnat_set_globals */
-/**********************/
+/***********************************/
+/* __gnat_get_specific_dispatching */
+/***********************************/
-/* This routine is called from the binder generated main program. It copies
- the values for global quantities computed by the binder into the following
- global locations. The reason that we go through this copy, rather than just
- define the global locations in the binder generated file, is that they are
- referenced from the runtime, which may be in a shared library, and the
- binder file is not in the shared library. Global references across library
- boundaries like this are not handled correctly in all systems. */
+char __gnat_get_specific_dispatching (int);
-/* For detailed description of the parameters to this routine, see the
- section titled Run-Time Globals in package Bindgen (bindgen.adb) */
+/* This routine is called from the runtime 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. */
-void
-__gnat_set_globals (int main_priority,
- int time_slice_val,
- char wc_encoding,
- char locking_policy,
- char queuing_policy,
- char task_dispatching_policy,
- char *restrictions,
- char *interrupt_states,
- int num_interrupt_states,
- int unreserve_all_interrupts,
- int exception_tracebacks,
- int zero_cost_exceptions,
- int detect_blocking)
+char
+__gnat_get_specific_dispatching (int priority)
{
- static int already_called = 0;
-
- /* If this procedure has been already called once, check that the
- arguments in this call are consistent with the ones in the previous
- calls. Otherwise, raise a Program_Error exception.
-
- We do not check for consistency of the wide character encoding
- method. This default affects only Wide_Text_IO where no explicit
- coding method is given, and there is no particular reason to let
- this default be affected by the source representation of a library
- in any case.
-
- We do not check either for the consistency of exception tracebacks,
- because exception tracebacks are not normally set in Stand-Alone
- libraries. If a library or the main program set the exception
- tracebacks, then they are never reset afterwards (see below).
-
- The value of main_priority is meaningful only when we are invoked
- from the main program elaboration routine of an Ada application.
- Checking the consistency of this parameter should therefore not be
- done. Since it is assured that the main program elaboration will
- always invoke this procedure before any library elaboration
- routine, only the value of main_priority during the first call
- should be taken into account and all the subsequent ones should be
- ignored. Note that the case where the main program is not written
- in Ada is also properly handled, since the default value will then
- be used for this parameter.
-
- For identical reasons, the consistency of time_slice_val should not
- be checked. */
-
- if (already_called)
- {
- if (__gl_locking_policy != locking_policy
- || __gl_queuing_policy != queuing_policy
- || __gl_task_dispatching_policy != task_dispatching_policy
- || __gl_unreserve_all_interrupts != unreserve_all_interrupts
- || __gl_zero_cost_exceptions != zero_cost_exceptions)
- __gnat_raise_program_error (__FILE__, __LINE__);
+ if (__gl_num_specific_dispatching == 0)
+ return ' ';
+ else if (priority >= __gl_num_specific_dispatching)
+ return 'F';
+ else
+ return __gl_priority_specific_dispatching [priority];
+}
- /* If either a library or the main program set the exception traceback
- flag, it is never reset later */
+#ifndef IN_RTS
- if (exception_tracebacks != 0)
- __gl_exception_tracebacks = exception_tracebacks;
+/**********************/
+/* __gnat_set_globals */
+/**********************/
- return;
- }
- already_called = 1;
-
- __gl_main_priority = main_priority;
- __gl_time_slice_val = time_slice_val;
- __gl_wc_encoding = wc_encoding;
- __gl_locking_policy = locking_policy;
- __gl_queuing_policy = queuing_policy;
- __gl_restrictions = restrictions;
- __gl_interrupt_states = interrupt_states;
- __gl_num_interrupt_states = num_interrupt_states;
- __gl_task_dispatching_policy = task_dispatching_policy;
- __gl_unreserve_all_interrupts = unreserve_all_interrupts;
- __gl_exception_tracebacks = exception_tracebacks;
- __gl_detect_blocking = detect_blocking;
-
- /* ??? __gl_zero_cost_exceptions is new in 3.15 and is referenced from
- a-except.adb, which is also part of the compiler sources. Since the
- compiler is built with an older release of GNAT, the call generated by
- the old binder to this function does not provide any value for the
- corresponding argument, so the global has to be initialized in some
- reasonable other way. This could be removed as soon as the next major
- release is out. */
+/* This routine is kept for bootstrapping purposes, since the binder generated
+ file now sets the __gl_* variables directly. */
-#ifdef IN_RTS
- __gl_zero_cost_exceptions = zero_cost_exceptions;
-#else
- __gl_zero_cost_exceptions = 0;
- /* We never build the compiler to run in ZCX mode currently anyway. */
-#endif
+void
+__gnat_set_globals (void)
+{
}
-/* 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 currently 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 our current approach. Basically: on some
- targets the adjustment to apply depends on the triggering signal, which is
- not easily accessible from the macro, and we actually do not tackle this as
- of today. Besides, other languages, e.g. Java, deal with this by performing
- the adjustment in the signal handler before the raise, so our adjustments
- may break those front-ends.
-
- To have it all right, we should either find a way to deal with the signal
- variants from the macro and convert Java on all targets (ugh), or remove
- our macro adjustments and update our signal handlers a-la-java way. The
- latter option appears the simplest, although some targets have their share
- of subtleties to account for. See for instance the syscall(SYS_sigaction)
- story in libjava/include/i386-signal.h. */
+#endif
/***************/
/* AIX Section */
#include <signal.h>
#include <sys/time.h>
-/* Some versions of AIX don't define SA_NODEFER. */
+/* 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. */
+ nsleep instead. */
#ifndef _AIXVERSION_430
#endif /* _AIXVERSION_430 */
-static void __gnat_error_handler (int);
+static void __gnat_error_handler (int sig, siginfo_t * si, void * uc);
static void
-__gnat_error_handler (int sig)
+__gnat_error_handler (int sig,
+ siginfo_t * si ATTRIBUTE_UNUSED,
+ void * uc ATTRIBUTE_UNUSED)
{
struct Exception_Data *exception;
const char *msg;
switch (sig)
{
case SIGSEGV:
- /* FIXME: we need to detect the case of a *real* SIGSEGV */
+ /* FIXME: we need to detect the case of a *real* SIGSEGV. */
exception = &storage_error;
msg = "stack overflow or erroneous memory access";
break;
/* 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! */
+ signal that might cause a scheduling event! */
- act.sa_handler = __gnat_error_handler;
- act.sa_flags = SA_NODEFER | SA_RESTART;
+ act.sa_flags = SA_NODEFER | SA_RESTART | SA_SIGINFO;
+ act.sa_sigaction = __gnat_error_handler;
sigemptyset (&act.sa_mask);
- /* Do not install handlers if interrupt state is "System" */
+ /* 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')
extern void __gnat_set_code_loc (struct sigcontext *, char *);
extern size_t __gnat_machine_state_length (void);
+#define HAVE_GNAT_ADJUST_CONTEXT_FOR_RAISE
+
+void
+__gnat_adjust_context_for_raise (int signo, void *ucontext)
+{
+ struct sigcontext *sigcontext = (struct sigcontext *) ucontext;
+
+ /* The unwinder expects the signal context to contain the address of the
+ faulting instruction. For SIGFPE, this depends on the trap shadow
+ situation (see man ieee). We nonetheless always compensate for it,
+ considering that PC designates the instruction following the one that
+ trapped. This is not necessarily true but corresponds to what we have
+ always observed. */
+ if (signo == SIGFPE)
+ sigcontext->sc_pc--;
+}
+
static void
-__gnat_error_handler
- (int sig, siginfo_t *sip, struct sigcontext *context ATTRIBUTE_UNUSED)
+__gnat_error_handler (int sig, siginfo_t *sip, struct sigcontext *context)
{
struct Exception_Data *exception;
static int recurse = 0;
const char *msg;
+ /* Adjusting is required for every fault context, so adjust for this one
+ now, before we possibly trigger a recursive fault below. */
+ __gnat_adjust_context_for_raise (sig, context);
+
/* If this was an explicit signal from a "kill", just resignal it. */
if (SI_FROMUSER (sip))
{
}
recurse = 0;
- Raise_From_Signal_Handler (exception, (char *) msg);
+ Raise_From_Signal_Handler (exception, (const char *) msg);
}
void
/* 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! */
+ 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" */
+ /* 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')
context->sc_pc = (long) pc;
}
-
size_t
__gnat_machine_state_length (void)
{
return sizeof (struct sigcontext);
}
-/********************/
-/* PA HP-UX section */
-/********************/
+/*****************/
+/* HP-UX section */
+/*****************/
-#elif defined (__hppa__) && defined (__hpux__)
+#elif defined (__hpux__)
#include <signal.h>
#include <sys/ucontext.h>
static void
__gnat_error_handler (int sig, 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 (UseWideRegs (mcontext))
- mcontext->ss_wide.ss_32.ss_pcoq_head_lo ++;
- else
- mcontext->ss_narrow.ss_pcoq_head ++;
-}
-
static void
__gnat_error_handler
- (int sig, siginfo_t *siginfo ATTRIBUTE_UNUSED, void *ucontext)
+ (int sig,
+ siginfo_t *siginfo ATTRIBUTE_UNUSED,
+ void *ucontext ATTRIBUTE_UNUSED)
{
struct Exception_Data *exception;
const char *msg;
switch (sig)
{
case SIGSEGV:
- /* FIXME: we need to detect the case of a *real* SIGSEGV */
+ /* FIXME: we need to detect the case of a *real* SIGSEGV. */
exception = &storage_error;
msg = "stack overflow or erroneous memory access";
break;
msg = "unhandled signal";
}
- __gnat_adjust_context_for_raise (sig, ucontext);
-
Raise_From_Signal_Handler (exception, msg);
}
+/* This must be in keeping with System.OS_Interface.Alternate_Stack_Size. */
+#if defined (__hppa__)
+char __gnat_alternate_stack[16 * 1024]; /* 2 * SIGSTKSZ */
+#else
+char __gnat_alternate_stack[128 * 1024]; /* MINSIGSTKSZ */
+#endif
+
void
__gnat_install_handler (void)
{
/* 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
+ 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). */
+ handler itself. */
stack_t stack;
-
- stack.ss_sp = handler_stack;
- stack.ss_size = sizeof (handler_stack);
+ stack.ss_sp = __gnat_alternate_stack;
+ stack.ss_size = sizeof (__gnat_alternate_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;
+ act.sa_flags = SA_NODEFER | SA_RESTART | SA_SIGINFO;
sigemptyset (&act.sa_mask);
- /* Do not install handlers if interrupt state is "System" */
+ /* 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);
+ act.sa_flags |= SA_ONSTACK;
+ if (__gnat_get_interrupt_state (SIGSEGV) != 's')
+ sigaction (SIGSEGV, &act, NULL);
__gnat_handler_installed = 1;
}
/* GNU/Linux Section */
/*********************/
-#elif defined (linux) && (defined (i386) || defined (__x86_64__) \
- || defined (__ia64__))
+#elif defined (linux)
#include <signal.h>
#include <sys/ucontext.h>
/* GNU/Linux, which uses glibc, does not define NULL in included
- header files */
+ 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. */
+#if defined (i386) || defined (__x86_64__) || defined (__ia64__)
#define HAVE_GNAT_ADJUST_CONTEXT_FOR_RAISE
{
mcontext_t *mcontext = &((ucontext_t *) ucontext)->uc_mcontext;
+ /* On the i386 and x86-64 architectures, we specifically detect calls to
+ the null address and entirely fold the not-yet-fully-established frame
+ to prevent it from stopping the unwinding.
+
+ On the i386 and x86-64 architectures, stack checking is performed by
+ means of probes with moving stack pointer, that is to say the probed
+ address is always the value of the stack pointer. Upon hitting the
+ guard page, the stack pointer therefore points to an inaccessible
+ address and an alternate signal stack is needed to run the handler.
+ But there is an additional twist: on these architectures, the EH
+ return code writes the address of the handler at the target CFA's
+ value on the stack before doing the jump. As a consequence, if
+ there is an active handler in the frame whose stack has overflowed,
+ the stack pointer must nevertheless point to an accessible address
+ by the time the EH return is executed.
+
+ We therefore adjust the saved value of the stack pointer by the size
+ of one page + a small dope of 4 words, in order to make sure that it
+ points to an accessible address in case it's used as the target CFA.
+ The stack checking code guarantees that this address is unused by the
+ time this happens. */
+
#if defined (i386)
- mcontext->gregs[REG_EIP]++;
+ unsigned long *pc = (unsigned long *)mcontext->gregs[REG_EIP];
+ /* The call insn pushes the return address onto the stack. Pop it. */
+ if (pc == NULL)
+ {
+ mcontext->gregs[REG_EIP] = *(unsigned long *)mcontext->gregs[REG_ESP];
+ mcontext->gregs[REG_ESP] += 4;
+ }
+ /* The pattern is "orl $0x0,(%esp)" for a probe in 32-bit mode. */
+ else if (signo == SIGSEGV && *pc == 0x00240c83)
+ mcontext->gregs[REG_ESP] += 4096 + 4 * sizeof (unsigned long);
#elif defined (__x86_64__)
- mcontext->gregs[REG_RIP]++;
+ unsigned long *pc = (unsigned long *)mcontext->gregs[REG_RIP];
+ /* The call insn pushes the return address onto the stack. Pop it. */
+ if (pc == NULL)
+ {
+ mcontext->gregs[REG_RIP] = *(unsigned long *)mcontext->gregs[REG_RSP];
+ mcontext->gregs[REG_RSP] += 8;
+ }
+ /* The pattern is "orq $0x0,(%rsp)" for a probe in 64-bit mode. */
+ else if (signo == SIGSEGV && (*pc & 0xffffffffff) == 0x00240c8348)
+ mcontext->gregs[REG_RSP] += 4096 + 4 * sizeof (unsigned long);
#elif defined (__ia64__)
+ /* ??? The IA-64 unwinder doesn't compensate for signals. */
mcontext->sc_ip++;
#endif
}
+#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;
+ const char *msg;
+
+ /* Adjusting is required for every fault context, so adjust for this one
+ now, before we possibly trigger a recursive fault below. */
+ __gnat_adjust_context_for_raise (sig, ucontext);
switch (sig)
{
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 */
+ occur as the result of an erroneous program. */
msg = "stack overflow (or erroneous memory access)";
exception = &storage_error;
exception = &program_error;
msg = "unhandled signal";
}
+
recurse = 0;
+ Raise_From_Signal_Handler (exception, msg);
+}
- /* 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. */
+#if defined (i386) || defined (__x86_64__)
+/* This must be in keeping with System.OS_Interface.Alternate_Stack_Size. */
+char __gnat_alternate_stack[16 * 1024]; /* 2 * SIGSTKSZ */
+#endif
- __gnat_adjust_context_for_raise (sig, ucontext);
+#ifdef __XENO__
+#include <sys/mman.h>
+#include <native/task.h>
- Raise_From_Signal_Handler (exception, msg);
-}
+RT_TASK main_task;
+#endif
void
__gnat_install_handler (void)
{
struct sigaction act;
+#ifdef __XENO__
+ int prio;
+
+ if (__gl_main_priority == -1)
+ prio = 49;
+ else
+ prio = __gl_main_priority;
+
+ /* Avoid memory swapping for this program */
+
+ mlockall (MCL_CURRENT|MCL_FUTURE);
+
+ /* Turn the current Linux task into a native Xenomai task */
+
+ rt_task_shadow(&main_task, "environment_task", prio, T_FPU);
+#endif
+
/* 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! */
+ 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. */
+
+#if defined (i386) || defined (__x86_64__)
+ stack_t stack;
+ stack.ss_sp = __gnat_alternate_stack;
+ stack.ss_size = sizeof (__gnat_alternate_stack);
+ stack.ss_flags = 0;
+ sigaltstack (&stack, NULL);
+#endif
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" */
+ /* 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 defined (i386) || defined (__x86_64__)
+ act.sa_flags |= SA_ONSTACK;
+#endif
if (__gnat_get_interrupt_state (SIGSEGV) != 's')
sigaction (SIGSEGV, &act, NULL);
#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
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.
-*/
+ process's context when the signal was delivered. */
static void
__gnat_error_handler (int sig, int code, sigcontext_t *sc ATTRIBUTE_UNUSED)
/* ??? Re-add smarts to further verify that we launched
the stack into a guard page, not an attempt to
- write to .text or something */
+ write to .text or something. */
exception = &storage_error;
msg = "SIGSEGV: (stack overflow or erroneous memory access)";
}
/* 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 */
+ on knowing all the codes. */
exception = &program_error;
msg = "SIGSEGV: (Undocumented reason)";
}
break;
default:
- /* Everything else is a Program_Error. */
+ /* Everything else is a Program_Error. */
exception = &program_error;
msg = "unhandled signal";
}
/* 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! */
+ 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" */
+ /* 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')
}
/*******************/
-/* Solaris Section */
+/* LynxOS Section */
/*******************/
-#elif defined (sun) && defined (__SVR4) && !defined (__vxworks)
+#elif defined (__Lynx__)
#include <signal.h>
-#include <siginfo.h>
-
-static void __gnat_error_handler (int, siginfo_t *);
+#include <unistd.h>
static void
-__gnat_error_handler (int sig, siginfo_t *sip)
+__gnat_error_handler (int sig)
{
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)
- {
+ switch(sig)
+ {
+ case SIGFPE:
+ exception = &constraint_error;
+ msg = "SIGFPE";
+ break;
+ case SIGILL:
+ exception = &constraint_error;
+ msg = "SIGILL";
+ break;
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)";
- }
+ 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";
+ msg = "SIGBUS";
break;
-
default:
exception = &program_error;
msg = "unhandled signal";
}
- recurse = 0;
-
- Raise_From_Signal_Handler (exception, msg);
+ Raise_From_Signal_Handler(exception, msg);
}
void
-__gnat_install_handler (void)
+__gnat_install_handler(void)
{
struct sigaction act;
- /* Set up signal handler to map synchronous signals to appropriate
+ act.sa_handler = __gnat_error_handler;
+ act.sa_flags = 0x0;
+ 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;
+}
+
+/*******************/
+/* Solaris Section */
+/*******************/
+
+#elif defined (sun) && defined (__SVR4) && !defined (__vxworks)
+
+#include <signal.h>
+#include <siginfo.h>
+#include <sys/ucontext.h>
+#include <sys/regset.h>
+
+/* The code below is common to SPARC and x86. Beware of the delay slot
+ differences for signal context adjustments. */
+
+#if defined (__sparc)
+#define RETURN_ADDR_OFFSET 8
+#else
+#define RETURN_ADDR_OFFSET 0
+#endif
+
+/* Likewise regarding how the "instruction pointer" register slot can
+ be identified in signal machine contexts. We have either "REG_PC"
+ or "PC" at hand, depending on the target CPU and Solaris version. */
+#if !defined (REG_PC)
+#define REG_PC PC
+#endif
+
+static void __gnat_error_handler (int, siginfo_t *, void *);
+
+#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;
+ unsigned long *pc = (unsigned long *)mcontext->gregs[REG_PC];
+
+ /* We specifically detect calls to the null address and entirely fold
+ the not-yet-fully-established frame to prevent it from stopping the
+ unwinding. */
+ if (pc == NULL)
+#if defined (__sparc)
+ /* The call insn moves the return address into %o7. Move it back. */
+ mcontext->gregs[REG_PC] = mcontext->gregs[REG_O7];
+#elif defined (i386)
+ {
+ /* The call insn pushes the return address onto the stack. Pop it. */
+ mcontext->gregs[REG_PC] = *(unsigned long *)mcontext->gregs[UESP];
+ mcontext->gregs[UESP] += 4;
+ }
+#elif defined (__x86_64__)
+ {
+ /* The call insn pushes the return address onto the stack. Pop it. */
+ mcontext->gregs[REG_PC] = *(unsigned long *)mcontext->gregs[REG_RSP];
+ mcontext->gregs[REG_RSP] += 8;
+ }
+#else
+#error architecture not supported on Solaris
+#endif
+}
+
+static void
+__gnat_error_handler (int sig, siginfo_t *sip, void *ucontext)
+{
+ struct Exception_Data *exception;
+ static int recurse = 0;
+ const char *msg;
+
+ /* Adjusting is required for every fault context, so adjust for this one
+ now, before we possibly trigger a recursive fault below. */
+ __gnat_adjust_context_for_raise (sig, ucontext);
+
+ 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 == 0
+ || (((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! */
+ 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" */
+ /* 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')
#elif defined (VMS)
+/* Routine called from binder to override default feature values. */
+void __gnat_set_features ();
+int __gnat_features_set = 0;
+
long __gnat_error_handler (int *, void *);
#ifdef __IA64
#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). */
+/* 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 */
/* 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. */
+ 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 */
+ them to be used in a case statement below. */
#define SS$_ACCVIO 12
#define SS$_HPARITH 1284
#define SS$_STKOVF 1364
#define SS$_RESIGNAL 2328
-/* These codes are in standard message libraries */
+/* These codes are in standard message libraries. */
+extern int C$_SIGKILL;
extern int CMA$_EXIT_THREAD;
extern int SS$_DEBUG;
extern int SS$_INTDIV;
/* These codes are non standard, which is to say the author is
not sure if they are defined in the standard message libraries
- so keep them as macros for now. */
+ so keep them as macros for now. */
#define RDB$_STREAM_EOF 20480426
#define FDL$_UNPRIKW 11829410
/* Conditions that don't have an Ada exception counterpart must raise
Non_Ada_Error. Since this is defined in s-auxdec, it should only be
- referenced by user programs, not the compiler or tools. Hence the
- #ifdef IN_RTS. */
+ referenced by user programs, not the compiler or tools. Hence the
+ #ifdef IN_RTS. */
#ifdef IN_RTS
extern Exception_Code Base_Code_In (Exception_Code);
/* DEC Ada exceptions are not defined in a header file, so they
- must be declared as external addresses */
-
-extern int ADA$_PROGRAM_ERROR __attribute__ ((weak));
-extern int ADA$_LOCK_ERROR __attribute__ ((weak));
-extern int ADA$_EXISTENCE_ERROR __attribute__ ((weak));
-extern int ADA$_KEY_ERROR __attribute__ ((weak));
-extern int ADA$_KEYSIZERR __attribute__ ((weak));
-extern int ADA$_STAOVF __attribute__ ((weak));
-extern int ADA$_CONSTRAINT_ERRO __attribute__ ((weak));
-extern int ADA$_IOSYSFAILED __attribute__ ((weak));
-extern int ADA$_LAYOUT_ERROR __attribute__ ((weak));
-extern int ADA$_STORAGE_ERROR __attribute__ ((weak));
-extern int ADA$_DATA_ERROR __attribute__ ((weak));
-extern int ADA$_DEVICE_ERROR __attribute__ ((weak));
-extern int ADA$_END_ERROR __attribute__ ((weak));
-extern int ADA$_MODE_ERROR __attribute__ ((weak));
-extern int ADA$_NAME_ERROR __attribute__ ((weak));
-extern int ADA$_STATUS_ERROR __attribute__ ((weak));
-extern int ADA$_NOT_OPEN __attribute__ ((weak));
-extern int ADA$_ALREADY_OPEN __attribute__ ((weak));
-extern int ADA$_USE_ERROR __attribute__ ((weak));
-extern int ADA$_UNSUPPORTED __attribute__ ((weak));
-extern int ADA$_FAC_MODE_MISMAT __attribute__ ((weak));
-extern int ADA$_ORG_MISMATCH __attribute__ ((weak));
-extern int ADA$_RFM_MISMATCH __attribute__ ((weak));
-extern int ADA$_RAT_MISMATCH __attribute__ ((weak));
-extern int ADA$_MRS_MISMATCH __attribute__ ((weak));
-extern int ADA$_MRN_MISMATCH __attribute__ ((weak));
-extern int ADA$_KEY_MISMATCH __attribute__ ((weak));
-extern int ADA$_MAXLINEXC __attribute__ ((weak));
-extern int ADA$_LINEXCMRS __attribute__ ((weak));
-
-/* DEC Ada specific conditions */
+ 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$_USE_ERROR, &Use_Error},
#endif /* IN_RTS */
-/* Non DEC Ada specific conditions. We could probably also put
- SS$_HPARITH here and possibly SS$_ACCVIO, SS$_STKOVF. */
+/* 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$_INTDIV, &constraint_error},
still need to be handled by such handlers, however, in which case
__gnat_error_handler needs to return SS$_RESIGNAL. Consider for
instance the use of a third party library compiled with DECAda and
- performing it's own exception handling internally.
+ performing its own exception handling internally.
To allow some user-level flexibility, which conditions should be
resignaled is controlled by a predicate function, provided with the
resignal_predicate (int code);
const int *cond_resignal_table [] = {
+ &C$_SIGKILL,
&CMA$_EXIT_THREAD,
&SS$_DEBUG,
&LIB$_KEYNOTFOU,
0
};
+const int facility_resignal_table [] = {
+ 0x1380000, /* RDB */
+ 0x2220000, /* SQL */
+ 0
+};
+
/* Default GNAT predicate for resignaling conditions. */
static int
{
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$MATCH_COND (&code, &cond_resignal_table [i]));
__gnat_resignal_p = predicate;
}
-/* Should match System.Parameters.Default_Exception_Msg_Max_Length */
+/* Should match System.Parameters.Default_Exception_Msg_Max_Length. */
#define Default_Exception_Msg_Max_Length 512
-/* Action routine for SYS$PUTMSG. There may be
- multiple conditions, each with text to be appended to
- MESSAGE and separated by line termination. */
+/* Action routine for SYS$PUTMSG. There may be multiple
+ conditions, each with text to be appended to MESSAGE
+ and separated by line termination. */
static int
copy_msg (msgdesc, message)
int len = strlen (message);
int copy_len;
- /* Check for buffer overflow and skip */
+ /* Check for buffer overflow and skip. */
if (len > 0 && len <= Default_Exception_Msg_Max_Length - 3)
{
strcat (message, "\r\n");
len += 2;
}
- /* Check for buffer overflow and truncate if necessary */
+ /* Check for buffer overflow and truncate if necessary. */
copy_len = (len + msgdesc->len <= Default_Exception_Msg_Max_Length - 1 ?
msgdesc->len :
Default_Exception_Msg_Max_Length - 1 - len);
}
long
-__gnat_error_handler (int *sigargs, void *mechargs)
+__gnat_handle_vms_condition (int *sigargs, void *mechargs)
{
struct Exception_Data *exception = 0;
Exception_Code base_code;
char message [Default_Exception_Msg_Max_Length];
const char *msg = "";
- char curr_icb[544];
- long curr_invo_handle;
/* Check for conditions to resignal which aren't effected by pragma
Import_Exception. */
return SS$_RESIGNAL;
#ifdef IN_RTS
- /* See if it's an imported exception. Beware that registered exceptions
+ /* 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);
{
message [0] = 0;
- /* Subtract PC & PSL fields which messes with PUTMSG */
+ /* 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. ??? */
+ /* ??? The full name really should be get sys$getmsg returns. */
exception->Full_Name = "IMPORTED_EXCEPTION";
exception->Import_Code = base_code;
+
+#ifdef __IA64
+ /* Do not adjust the program counter as already points to the next
+ instruction (just after the call to LIB$STOP). */
+ Raise_From_Signal_Handler (exception, msg);
+#endif
}
#endif
exception = &storage_error;
msg = "stack overflow (or erroneous memory access)";
}
+ __gnat_adjust_context_for_raise (0, (void *)mechargs);
break;
case SS$_STKOVF:
exception = &storage_error;
msg = "stack overflow";
+ __gnat_adjust_context_for_raise (0, (void *)mechargs);
break;
case SS$_HPARITH:
#ifndef IN_RTS
return SS$_RESIGNAL; /* toplev.c handles for compiler */
#else
- {
- exception = &constraint_error;
- msg = "arithmetic error";
- }
+ exception = &constraint_error;
+ msg = "arithmetic error";
+#ifndef __alpha__
+ /* No need to adjust pc on Alpha: the pc is already on the instruction
+ after the trapping one. */
+ __gnat_adjust_context_for_raise (0, (void *)mechargs);
+#endif
#endif
break;
int i;
/* Scan the DEC Ada exception condition table for a match and fetch
- the associated GNAT exception pointer */
+ the associated GNAT exception pointer. */
for (i = 0;
dec_ada_cond_except_table [i].cond &&
!LIB$MATCH_COND (&sigargs [1],
if (!exception)
{
/* Scan the VMS standard condition table for a match and fetch
- the associated GNAT exception pointer */
+ the associated GNAT exception pointer. */
for (i = 0;
cond_except_table [i].cond &&
!LIB$MATCH_COND (&sigargs [1], &cond_except_table [i].cond);
i++);
- exception =(struct Exception_Data *) cond_except_table [i].except;
+ exception = (struct Exception_Data *)
+ cond_except_table [i].except;
if (!exception)
/* User programs expect Non_Ada_Error to be raised, reference
- DEC Ada test CXCONDHAN. */
+ DEC Ada test CXCONDHAN. */
exception = &Non_Ada_Error;
}
}
exception = &program_error;
#endif
message [0] = 0;
- /* Subtract PC & PSL fields which messes with PUTMSG */
+ /* Subtract PC & PSL fields which messes with PUTMSG. */
sigargs [0] -= 2;
SYS$PUTMSG (sigargs, copy_msg, &gnat_facility, message);
sigargs [0] += 2;
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;
-#if defined (IN_RTS) && !defined (__IA64)
- char *c;
+ long prvhnd ATTRIBUTE_UNUSED;
- c = (char *) xmalloc (2049);
+#if !defined (IN_RTS)
+ SYS$SETEXV (1, __gnat_error_handler, 3, &prvhnd);
+#endif
- __gnat_error_prehandler_stack = &c[2048];
+ /* On alpha-vms, we avoid the global vector annoyance thanks to frame based
+ handlers to turn conditions into exceptions since GCC 3.4. The global
+ vector is still required for earlier GCC versions. We're resorting to
+ the __gnat_error_prehandler assembly function in this case. */
- /* __gnat_error_prehandler is an assembly function. */
- SYS$SETEXV (1, __gnat_error_prehandler, 3, &prvhnd);
-#else
-#if defined (IN_RTS) && defined (__IA64)
- if (getenv ("DBG$TDBG"))
- printf ("DBG$TDBG defined, __gnat_error_handler not installed!\n");
- else
-#endif
- SYS$SETEXV (1, __gnat_error_handler, 3, &prvhnd);
+#if defined (IN_RTS) && defined (__alpha__)
+ if ((__GNUC__ * 10 + __GNUC_MINOR__) < 34)
+ {
+ char * c = (char *) xmalloc (2049);
+
+ __gnat_error_prehandler_stack = &c[2048];
+ SYS$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$l_sig_args;
+
+ u64 * ih_pc_loc = post_sigarray - 2;
+
+ (*ih_pc_loc) ++;
+}
+
+#endif
+
+/* Feature logical name and global variable address pair */
+struct feature {char *name; int* gl_addr;};
+
+/* Default values for GNAT features set by environment. */
+int __gl_no_malloc_64 = 0;
+
+/* Array feature logical names and global variable addresses */
+static struct feature features[] = {
+ {"GNAT$NO_MALLOC_64", &__gl_no_malloc_64},
+ {0, 0}
+};
+
+void __gnat_set_features ()
+{
+ struct descriptor_s name_desc, result_desc;
+ int i, status;
+ unsigned short rlen;
+
+#define MAXEQUIV 10
+ char buff [MAXEQUIV];
+
+ /* Loop through features array and test name for enable/disable */
+ for (i=0; features [i].name; i++)
+ {
+ name_desc.len = strlen (features [i].name);
+ name_desc.mbz = 0;
+ name_desc.adr = features [i].name;
+
+ result_desc.len = MAXEQUIV - 1;
+ result_desc.mbz = 0;
+ result_desc.adr = buff;
+
+ status = LIB$GET_LOGICAL (&name_desc, &result_desc, &rlen);
+
+ if (((status & 1) == 1) && (rlen < MAXEQUIV))
+ buff [rlen] = 0;
+ else
+ strcpy (buff, "");
+
+ if (strcmp (buff, "ENABLE") == 0)
+ *features [i].gl_addr = 1;
+ else if (strcmp (buff, "DISABLE") == 0)
+ *features [i].gl_addr = 0;
+ }
+
+ __gnat_features_set = 1;
+}
+
/*******************/
/* FreeBSD Section */
/*******************/
#elif defined (__FreeBSD__)
#include <signal.h>
+#include <sys/ucontext.h>
#include <unistd.h>
-static void __gnat_error_handler (int, int, struct sigcontext *);
+static void __gnat_error_handler (int, siginfo_t *, ucontext_t *);
static void
-__gnat_error_handler (int sig, int code __attribute__ ((unused)),
- struct sigcontext *sc __attribute__ ((unused)))
+__gnat_error_handler (int sig, siginfo_t *info __attribute__ ((unused)),
+ ucontext_t *ucontext)
{
struct Exception_Data *exception;
const char *msg;
/* 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! */
+ signal that might cause a scheduling event! */
- act.sa_handler = __gnat_error_handler;
- act.sa_flags = SA_NODEFER | SA_RESTART;
+ 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);
#include "private/vThreadsP.h"
#endif
-static void __gnat_error_handler (int, int, struct sigcontext *);
-void __gnat_map_signal (int);
+void __gnat_error_handler (int, void *, struct sigcontext *);
#ifndef __RTP__
-/* Directly vectored Interrupt routines are not supported when using RTPs */
+/* 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 */
+/* This is needed by the GNAT run time to handle Vxworks interrupts. */
int
__gnat_inum_to_ivec (int num)
{
#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). */
+ on Alpha VxWorks and VxWorks 6.x (including RTPs). */
extern long getpid (void);
}
#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 */
+/* VxWorks 653 vThreads expects the field excCnt to be zeroed when a signal is.
+ handled. The VxWorks version of longjmp does this; GCC's builtin_longjmp
+ doesn't. */
void
__gnat_clear_exception_count (void)
{
#endif
}
-/* Exported to s-intman-vxworks.adb in order to handle different signal
- to exception mappings in different VxWorks versions */
-void
+/* Handle different SIGnal to exception mappings in different VxWorks
+ versions. */
+static void
__gnat_map_signal (int sig)
{
struct Exception_Data *exception;
msg = "SIGFPE";
break;
#ifdef VTHREADS
+#ifdef __VXWORKSMILS__
+ case SIGILL:
+ exception = &storage_error;
+ msg = "SIGILL: possible stack overflow";
+ break;
+ case SIGSEGV:
+ exception = &storage_error;
+ msg = "SIGSEGV";
+ break;
+ case SIGBUS:
+ exception = &program_error;
+ msg = "SIGBUS";
+ break;
+#else
case SIGILL:
exception = &constraint_error;
msg = "Floating point exception or SIGILL";
break;
case SIGSEGV:
exception = &storage_error;
- msg = "SIGSEGV: possible stack overflow";
+ msg = "SIGSEGV";
break;
case SIGBUS:
exception = &storage_error;
msg = "SIGBUS: possible stack overflow";
break;
-#else
+#endif
+#elif (_WRS_VXWORKS_MAJOR == 6)
case SIGILL:
exception = &constraint_error;
msg = "SIGILL";
break;
+#ifdef __RTP__
+ /* In RTP mode a SIGSEGV is most likely due to a stack overflow,
+ since stack checking uses the probing mechanism. */
case SIGSEGV:
+ exception = &storage_error;
+ msg = "SIGSEGV: possible stack overflow";
+ break;
+ case SIGBUS:
exception = &program_error;
+ msg = "SIGBUS";
+ break;
+#else
+ /* VxWorks 6 kernel mode with probing. SIGBUS for guard page hit */
+ case SIGSEGV:
+ exception = &storage_error;
+ msg = "SIGSEGV";
+ break;
+ case SIGBUS:
+ exception = &storage_error;
+ msg = "SIGBUS: possible stack overflow";
+ break;
+#endif
+#else
+ /* VxWorks 5: a SIGILL is most likely due to a stack overflow,
+ since stack checking uses the stack limit mechanism. */
+ case SIGILL:
+ exception = &storage_error;
+ msg = "SIGILL: possible stack overflow";
+ break;
+ case SIGSEGV:
+ exception = &storage_error;
msg = "SIGSEGV";
break;
case SIGBUS:
Raise_From_Signal_Handler (exception, msg);
}
-static void
-__gnat_error_handler (int sig, int code, struct sigcontext *sc)
+/* Tasking and Non-tasking signal handler. Map SIGnal to Ada exception
+ propagation after the required low level adjustments. */
+
+void
+__gnat_error_handler (int sig, void * si ATTRIBUTE_UNUSED,
+ 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. */
+ we unmask it. */
sigprocmask (SIG_SETMASK, NULL, &mask);
sigdelset (&mask, sig);
sigprocmask (SIG_SETMASK, &mask, NULL);
__gnat_map_signal (sig);
-
}
void
/* 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! */
+ 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 */
+ applies to vectored hardware interrupts, not signals. */
sigaction (SIGFPE, &act, NULL);
sigaction (SIGILL, &act, NULL);
sigaction (SIGSEGV, &act, NULL);
void
__gnat_init_float (void)
{
- /* Disable overflow/underflow exceptions on the PPC processor, this is needed
+ /* Disable overflow/underflow exceptions on the PPC processor, 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 */
+ below have no effect. */
#if defined (_ARCH_PPC) && !defined (_SOFT_FLOAT) && !defined (VTHREADS)
+#if defined (__SPE__)
+ {
+ const unsigned long spefscr_mask = 0xfffffff3;
+ unsigned long spefscr;
+ asm ("mfspr %0, 512" : "=r" (spefscr));
+ spefscr = spefscr & spefscr_mask;
+ asm ("mtspr 512, %0\n\tisync" : : "r" (spefscr));
+ }
+#else
asm ("mtfsb0 25");
asm ("mtfsb0 26");
#endif
+#endif
- /* Similarly for sparc64. Achieved by masking bits in the Trap Enable Mask
- field of the Floating-point Status Register (see the Sparc Architecture
+#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)
#endif
}
+/* This subprogram is called by System.Task_Primitives.Operations.Enter_Task
+ (if not null) when a new task is created. It is initialized by
+ System.Stack_Checking.Operations.Initialize_Stack_Limit.
+ The use of a hook avoids to drag stack checking subprograms if stack
+ checking is not used. */
+void (*__gnat_set_stack_limit_hook)(void) = (void (*)(void))0;
+
/******************/
/* NetBSD Section */
/******************/
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;
+}
+
+/*******************/
+/* OpenBSD Section */
+/*******************/
+
+#elif defined(__OpenBSD__)
+
+#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);
__gnat_handler_installed = 1;
}
+/******************/
+/* Darwin Section */
+/******************/
+
+#elif defined(__APPLE__)
+
+#include <signal.h>
+#include <sys/syscall.h>
+#include <mach/mach_vm.h>
+#include <mach/mach_init.h>
+#include <mach/vm_statistics.h>
+
+/* This must be in keeping with System.OS_Interface.Alternate_Stack_Size. */
+char __gnat_alternate_stack[32 * 1024]; /* 1 * MINSIGSTKSZ */
+
+static void __gnat_error_handler (int sig, siginfo_t * si, void * uc);
+
+/* Defined in xnu unix_signal.c.
+ Tell the kernel to re-use alt stack when delivering a signal. */
+#define UC_RESET_ALT_STACK 0x80000000
+
+/* Return true if ADDR is within a stack guard area. */
+static int
+__gnat_is_stack_guard (mach_vm_address_t addr)
+{
+ kern_return_t kret;
+ vm_region_submap_info_data_64_t info;
+ mach_vm_address_t start;
+ mach_vm_size_t size;
+ natural_t depth;
+ mach_msg_type_number_t count;
+
+ count = VM_REGION_SUBMAP_INFO_COUNT_64;
+ start = addr;
+ size = -1;
+ depth = 9999;
+ kret = mach_vm_region_recurse (mach_task_self (), &start, &size, &depth,
+ (vm_region_recurse_info_t) &info, &count);
+ if (kret == KERN_SUCCESS
+ && addr >= start && addr < (start + size)
+ && info.protection == VM_PROT_NONE
+ && info.user_tag == VM_MEMORY_STACK)
+ return 1;
+ return 0;
+}
+
+static void
+__gnat_error_handler (int sig, siginfo_t * si, void * uc ATTRIBUTE_UNUSED)
+{
+ struct Exception_Data *exception;
+ const char *msg;
+
+ switch (sig)
+ {
+ case SIGSEGV:
+ case SIGBUS:
+ if (__gnat_is_stack_guard ((unsigned long)si->si_addr))
+ {
+ exception = &storage_error;
+ msg = "stack overflow";
+ }
+ else
+ {
+ exception = &constraint_error;
+ msg = "erroneous memory access";
+ }
+ /* Reset the use of alt stack, so that the alt stack will be used
+ for the next signal delivery.
+ The stack can't be used in case of stack checking. */
+ syscall (SYS_sigreturn, NULL, UC_RESET_ALT_STACK);
+ 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! 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 (and it is required by Darwin). */
+
+ stack_t stack;
+ stack.ss_sp = __gnat_alternate_stack;
+ stack.ss_size = sizeof (__gnat_alternate_stack);
+ stack.ss_flags = 0;
+ sigaltstack (&stack, NULL);
+
+ act.sa_flags = SA_NODEFER | SA_RESTART | SA_SIGINFO;
+ act.sa_sigaction = __gnat_error_handler;
+ 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);
+
+ act.sa_flags |= SA_ONSTACK;
+ 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 */
+/* For all other versions of GNAT, the handler does nothing. */
/*******************/
/* Default Section */
/*********************/
/* 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 */
+ 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__)
+ || defined (__Lynx__) || defined(__NetBSD__) || defined(__FreeBSD__) \
+ || defined (__OpenBSD__)
#define HAVE_GNAT_INIT_FLOAT
void
__gnat_init_float (void)
{
-#if defined (__i386__) || defined (i386)
+#if defined (__i386__) || defined (i386) || defined (__x86_64)
/* This is used to properly initialize the FPU on an x86 for each
- process thread. */
+ process thread. */
asm ("finit");
#ifndef HAVE_GNAT_INIT_FLOAT
-/* All targets without a specific __gnat_init_float will use an empty one */
+/* All targets without a specific __gnat_init_float will use an empty one. */
void
__gnat_init_float (void)
{
#ifndef HAVE_GNAT_ADJUST_CONTEXT_FOR_RAISE
-/* All targets without a specific version will use an empty one */
+/* 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. */
+/* Given UCONTEXT a pointer to a context structure received by a signal
+ handler for SIGNO, perform the necessary adjustments to let the handler
+ raise an exception. Calls to this routine are not conditioned by the
+ propagation scheme in use. */
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.
+ /* We used to compensate here for the raised from call vs raised from signal
+ exception discrepancy with the GCC ZCX scheme, but this now can be dealt
+ with generically in the unwinder (see GCC PR other/26208). This however
+ requires the use of the _Unwind_GetIPInfo routine in raise-gcc.c, which
+ is predicated on the definition of HAVE_GETIPINFO at compile time. Only
+ the VMS ports still do the compensation described in the few lines below.
+
+ *** Call vs signal exception discrepancy with GCC ZCX scheme ***
+
+ 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 identified by a return
+ address, the propagation engine needs to determine what region the
+ corresponding call instruction pertains to. Because the return address
+ may not be attached to the same region as the call, the unwinder always
+ subtracts "some" amount from a return address to search the region
+ tables, amount chosen to ensure that the resulting address is inside the
+ call instruction.
+
+ 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 signal
+ context pushed by the kernel. Leaving this address untouched looses, if
+ the triggering instruction happens to be the very first of a region, as
+ the later adjustments performed by the unwinder would yield an address
+ outside that region. We need to compensate for the unwinder adjustments
+ at some point, and this is what this routine is expected to do.
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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