* *
* C Implementation File *
* *
- * Copyright (C) 1992-2005, Free Software Foundation, Inc. *
+ * Copyright (C) 1992-2008, 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- *
* 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, 59 Temple Place - Suite 330, Boston, *
- * MA 02111-1307, USA. *
+ * 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 *
* *
****************************************************************************/
-/* 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, and
- 5zinit.adb. All these files implement the required functionality for
- different targets. */
+/* 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. */
+ that the __vxworks header appear before any other include. */
#ifdef __vxworks
#include "vxWorks.h"
#endif
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 Get_Machine_State_Addr \
- system__soft_links__get_machine_state_addr
-extern struct Machine_State *(*Get_Machine_State_Addr) (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
-#define Propagate_Signal_Exception \
- __gnat_propagate_sig_exc
-extern void Propagate_Signal_Exception (struct Machine_State *,
- struct Exception_Data *,
- const char *);
-
-/* 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;
/* 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). */
+#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 ()
+{
}
-/*********************/
-/* __gnat_initialize */
-/*********************/
-
-/* __gnat_initialize is called at the start of execution of an Ada program
- (the call is generated by the binder). The standard routine does nothing
- at all; the intention is that this be replaced by system specific
- code where initialization is required. */
-
-/* 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 substracts "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 dependant (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 adjustements 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
-/***********************************/
-/* __gnat_initialize (AIX Version) */
-/***********************************/
+/***************/
+/* AIX Section */
+/***************/
#if defined (_AIX)
#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);
+
+/* __gnat_adjust_context_for_raise - see comments along with the default
+ version later in this file. */
+
+void
+__gnat_adjust_context_for_raise (int signo ATTRIBUTE_UNUSED, void *ucontext)
+{
+ /* We need to adjust the "Instruction Address Register" value, part of a
+ 'struct mstsave' wrapped as a jumpbuf in the mcontext field designated by
+ the signal data pointer we get. See sys/context.h + sys/mstsave.h */
+
+ mcontext_t *mcontext = &((ucontext_t *) ucontext)->uc_mcontext;
+ mcontext->jmp_context.iar++;
+}
+
+#define HAVE_GNAT_ADJUST_CONTEXT_FOR_RAISE
static void
-__gnat_error_handler (int sig)
+__gnat_error_handler (int sig, siginfo_t * si, void * uc)
{
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, uc);
Raise_From_Signal_Handler (exception, 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_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')
__gnat_handler_installed = 1;
}
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
-}
-
-/***************************************/
-/* __gnat_initialize (RTEMS version) */
-/***************************************/
-
-#elif defined(__rtems__)
-
-extern void __gnat_install_handler (void);
-
-/* For RTEMS, each bsp will provide a custom __gnat_install_handler (). */
-
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
- __gnat_install_handler ();
-}
-
-/****************************************/
-/* __gnat_initialize (Dec Unix Version) */
-/****************************************/
-
-#elif defined(__alpha__) && defined(__osf__) && ! defined(__alpha_vxworks)
+/*****************/
+/* Tru64 section */
+/*****************/
-/* Note: it seems that __osf__ is defined for the Alpha VXWorks case. Not
- clear that this is reasonable, but in any case we have to be sure to
- exclude this case in the above test. */
+#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_enter_handler (struct sigcontext *, char *);
+extern void __gnat_set_code_loc (struct sigcontext *, char *);
extern size_t __gnat_machine_state_length (void);
-extern long exc_lookup_gp (char *);
-extern void exc_resume (struct sigcontext *);
+/* __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, void *context)
+{
+ struct sigcontext * sigcontext = (struct sigcontext *) context;
+
+ /* The fallback code fetches the faulting insn address from sc_pc, so
+ adjust that when need be. For SIGFPE, the required adjustment depends
+ on the trap shadow situation (see man ieee). */
+ if (signo == SIGFPE)
+ {
+ /* ??? We never adjust here, considering that sc_pc always
+ designates the instruction following the one which trapped.
+ This is not necessarily true but corresponds to what we have
+ always observed. */
+ }
+ else
+ sigcontext->sc_pc ++;
+}
static void
-__gnat_error_handler (int sig, siginfo_t *sip, struct sigcontext *context)
+__gnat_error_handler
+ (int sig, siginfo_t *sip, struct sigcontext *context)
{
struct Exception_Data *exception;
static int recurse = 0;
- struct sigcontext *mstate;
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;
- mstate = (struct sigcontext *) (*Get_Machine_State_Addr) ();
- if (mstate != 0)
- *mstate = *context;
-
Raise_From_Signal_Handler (exception, (char *) msg);
}
/* 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')
__gnat_handler_installed = 1;
}
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
-}
-
/* Routines called by s-mastop-tru64.adb. */
#define SC_GP 29
}
void
-__gnat_enter_handler (struct sigcontext *context, char *pc)
+__gnat_set_code_loc (struct sigcontext *context, char *pc)
{
context->sc_pc = (long) pc;
- context->sc_regs[SC_GP] = exc_lookup_gp (pc);
- exc_resume (context);
}
size_t
return sizeof (struct sigcontext);
}
-/************************************/
-/* __gnat_initialize (HPUX Version) */
-/************************************/
+/*****************/
+/* HP-UX section */
+/*****************/
#elif defined (__hpux__)
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. */
mcontext->ss_narrow.ss_pcoq_head ++;
}
+#endif
+
static void
-__gnat_error_handler (int sig, siginfo_t *siginfo, void *ucontext)
+__gnat_error_handler
+ (int sig, siginfo_t *siginfo ATTRIBUTE_UNUSED, void *ucontext)
{
struct Exception_Data *exception;
- char *msg;
+ 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;
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;
}
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
-}
-
-/*****************************************/
-/* __gnat_initialize (GNU/Linux Version) */
-/*****************************************/
+/*********************/
+/* GNU/Linux Section */
+/*********************/
-#elif defined (linux) && defined (i386) && !defined (__RT__)
+#elif defined (linux) && (defined (i386) || defined (__x86_64__) \
+ || defined (__ia64__) || defined (__powerpc__))
#include <signal.h>
-#include <asm/sigcontext.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 */
+ header files. */
#if !defined (NULL)
#define NULL ((void *) 0)
#endif
-struct Machine_State
+#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)
{
- unsigned long eip;
- unsigned long ebx;
- unsigned long esp;
- unsigned long ebp;
- unsigned long esi;
- unsigned long edi;
-};
+#ifndef __powerpc__
+ mcontext_t *mcontext = &((ucontext_t *) ucontext)->uc_mcontext;
+#endif
-static void __gnat_error_handler (int);
+ /* 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, 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 page is unused by the time this happens. */
+
+#if defined (i386)
+ unsigned long pattern = *(unsigned long *)mcontext->gregs[REG_EIP];
+ /* The pattern is "orl $0x0,(%esp)" for a probe in 32-bit mode. */
+ if (signo == SIGSEGV && pattern == 0x00240c83)
+ mcontext->gregs[REG_ESP] += 4096;
+ mcontext->gregs[REG_EIP]++;
+#elif defined (__x86_64__)
+ unsigned long pattern = *(unsigned long *)mcontext->gregs[REG_RIP];
+ /* The pattern is "orq $0x0,(%rsp)" for a probe in 64-bit mode. */
+ if (signo == SIGSEGV && (pattern & 0xffffffffff) == 0x00240c8348)
+ mcontext->gregs[REG_RSP] += 4096;
+ mcontext->gregs[REG_RIP]++;
+#elif defined (__ia64__)
+ mcontext->sc_ip++;
+#elif defined (__powerpc__)
+ ((ucontext_t *) ucontext)->uc_mcontext.regs->nip++;
+#endif
+}
static void
-__gnat_error_handler (int sig)
+__gnat_error_handler (int sig,
+ siginfo_t *siginfo ATTRIBUTE_UNUSED,
+ void *ucontext)
{
struct Exception_Data *exception;
const char *msg;
static int recurse = 0;
- struct sigcontext *info
- = (struct sigcontext *) (((char *) &sig) + sizeof (int));
-
- /* The Linux kernel does not document how to get the machine state in a
- signal handler, but in fact the necessary data is in a sigcontext_struct
- value that is on the stack immediately above the signal number
- parameter, and the above messing accesses this value on the stack. */
-
- struct Machine_State *mstate;
-
switch (sig)
{
case SIGSEGV:
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;
- mstate = (*Get_Machine_State_Addr) ();
- if (mstate)
- {
- mstate->eip = info->eip;
- mstate->ebx = info->ebx;
- mstate->esp = info->esp_at_signal;
- mstate->ebp = info->ebp;
- mstate->esi = info->esi;
- mstate->edi = info->edi;
- }
+ /* 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);
- recurse = 0;
Raise_From_Signal_Handler (exception, msg);
}
+#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
+
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! */
+ 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. */
- act.sa_handler = __gnat_error_handler;
- act.sa_flags = SA_NODEFER | SA_RESTART;
+#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);
+#if defined (i386) || defined (__x86_64__)
+ act.sa_flags |= SA_ONSTACK;
+#endif
+ if (__gnat_get_interrupt_state (SIGSEGV) != 's')
+ sigaction (SIGSEGV, &act, NULL);
__gnat_handler_installed = 1;
}
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
-}
-
-/******************************************/
-/* __gnat_initialize (NT-mingw32 Version) */
-/******************************************/
+/****************/
+/* IRIX Section */
+/****************/
-#elif defined (__MINGW32__)
-#include <windows.h>
+#elif defined (sgi)
-void
-__gnat_install_handler (void)
-{
-}
+#include <signal.h>
+#include <siginfo.h>
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
- /* Initialize floating-point coprocessor. This call is needed because
- the MS libraries default to 64-bit precision instead of 80-bit
- precision, and we require the full precision for proper operation,
- given that we have set Max_Digits etc with this in mind */
- __gnat_init_float ();
-
- /* Initialize a lock for a process handle list - see a-adaint.c for the
- implementation of __gnat_portable_no_block_spawn, __gnat_portable_wait */
- __gnat_plist_init();
-
- /* Note that we do not activate this for the compiler itself to avoid a
- bootstrap path problem. Older version of gnatbind will generate a call
- to __gnat_initialize() without argument. Therefore we cannot use eh in
- this case. It will be possible to remove the following #ifdef at some
- point. */
-#ifdef IN_RTS
- /* Install the Structured Exception handler. */
- if (eh)
- __gnat_install_SEH_handler (eh);
+#ifndef NULL
+#define NULL 0
#endif
-}
-/***************************************/
-/* __gnat_initialize (Interix Version) */
-/***************************************/
+#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);
-#elif defined (__INTERIX)
+extern struct Exception_Data _abort_signal;
-#include <signal.h>
+static void __gnat_error_handler (int, int, sigcontext_t *);
-static void __gnat_error_handler (int);
+/* 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)
+__gnat_error_handler (int sig, int code, sigcontext_t *sc ATTRIBUTE_UNUSED)
{
struct Exception_Data *exception;
- char *msg;
+ const char *msg;
switch (sig)
{
case SIGSEGV:
- exception = &storage_error;
- msg = "stack overflow or erroneous memory access";
+ 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:
- exception = &constraint_error;
+ /* 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";
}
{
struct sigaction act;
- /* Set up signal handler to map synchronous signals to appropriate
+ /* 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 = 0;
+ act.sa_flags = SA_NODEFER + SA_RESTART;
+ sigfillset (&act.sa_mask);
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" */
+ /* 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;
}
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
- __gnat_init_float ();
-}
-
-/**************************************/
-/* __gnat_initialize (LynxOS Version) */
-/**************************************/
+/*******************/
+/* LynxOS Section */
+/*******************/
#elif defined (__Lynx__)
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
- __gnat_init_float ();
-}
-
-/*********************************/
-/* __gnat_install_handler (Lynx) */
-/*********************************/
-
-void
-__gnat_install_handler (void)
-{
- __gnat_handler_installed = 1;
-}
-
-/****************************/
-/* __gnat_initialize (OS/2) */
-/****************************/
-
-#elif defined (__EMX__) /* OS/2 dependent initialization */
-
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
-}
-
-/*********************************/
-/* __gnat_install_handler (OS/2) */
-/*********************************/
-
-void
-__gnat_install_handler (void)
-{
- __gnat_handler_installed = 1;
-}
-
-/***********************************/
-/* __gnat_initialize (SGI Version) */
-/***********************************/
-
-#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
-
-struct Machine_State
-{
- sigcontext_t context;
-};
-
-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.
-*/
+#include <unistd.h>
static void
-__gnat_error_handler (int sig, int code, sigcontext_t *sc)
+__gnat_error_handler (int sig)
{
- struct Machine_State *mstate;
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;
-
+ switch(sig)
+ {
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;
-
+ 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:
- /* Everything else is a Program_Error. */
exception = &program_error;
msg = "unhandled signal";
}
- mstate = (*Get_Machine_State_Addr) ();
- if (mstate != 0)
- memcpy ((void *) mstate, (const void *) sc, sizeof (sigcontext_t));
-
- Raise_From_Signal_Handler (exception, msg);
+ Raise_From_Signal_Handler(exception, msg);
}
void
-__gnat_install_handler (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);
+ act.sa_flags = 0x0;
sigemptyset (&act.sa_mask);
- /* Do not install handlers if interrupt state is "System" */
- if (__gnat_get_interrupt_state (SIGABRT) != 's')
- sigaction (SIGABRT, &act, NULL);
+ /* 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 (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;
}
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
-}
-
-/*************************************************/
-/* __gnat_initialize (Solaris and SunOS Version) */
-/*************************************************/
+/*******************/
+/* 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 *, ucontext_t *);
+
+/* __gnat_adjust_context_for_raise - see comments along with the default
+ version later in this file. */
+
+#define HAVE_GNAT_ADJUST_CONTEXT_FOR_RAISE
-static void __gnat_error_handler (int, siginfo_t *);
+void
+__gnat_adjust_context_for_raise (int signo ATTRIBUTE_UNUSED,
+ void * ucontext)
+{
+ mcontext_t *mcontext = & ((ucontext_t *)ucontext)->uc_mcontext;
+ mcontext->gregs[REG_PC] += (1 - RETURN_ADDR_OFFSET);
+}
static void
-__gnat_error_handler (int sig, siginfo_t *sip)
+__gnat_error_handler (int sig, siginfo_t *sip, ucontext_t *uctx)
{
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, (void *)uctx);
+
/* If this was an explicit signal from a "kill", just resignal it. */
if (SI_FROMUSER (sip))
{
/* 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')
__gnat_handler_installed = 1;
}
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
-}
-
-/***********************************/
-/* __gnat_initialize (VMS Version) */
-/***********************************/
+/***************/
+/* 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$I64_GET_PREV_INVO_CONTEXT
#if defined (IN_RTS) && !defined (__IA64)
-/* The prehandler actually gets control first on a condition. It swaps the
- stack pointer and calls the handler (__gnat_error_handler). */
+/* The prehandler actually gets control first on a condition. It swaps the
+ stack pointer and calls the handler (__gnat_error_handler). */
extern long __gnat_error_prehandler (void);
extern char *__gnat_error_prehandler_stack; /* Alternate signal stack */
#endif
+/* Define macro symbols for the VMS conditions that become Ada exceptions.
+ Most of these are also defined in the header file ssdef.h which has not
+ yet been converted to be recognized by GNU C. */
+
+/* Defining these as macros, as opposed to external addresses, allows
+ them to be used in a case statement below. */
+#define SS$_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$_UNPRIKW 11829410
+
+struct cond_except {
+ const int *cond;
+ const struct Exception_Data *except;
+};
+
+struct descriptor_s {unsigned short len, mbz; __char_ptr32 adr; };
+
/* Conditions that don't have an Ada exception counterpart must raise
Non_Ada_Error. Since this is defined in s-auxdec, it should only be
- referenced by user programs, not the compiler or tools. Hence the
- #ifdef IN_RTS. */
+ referenced by user programs, not the compiler or tools. Hence the
+ #ifdef IN_RTS. */
#ifdef IN_RTS
+
+#define Status_Error ada__io_exceptions__status_error
+extern struct Exception_Data Status_Error;
+
+#define Mode_Error ada__io_exceptions__mode_error
+extern struct Exception_Data Mode_Error;
+
+#define Name_Error ada__io_exceptions__name_error
+extern struct Exception_Data Name_Error;
+
+#define Use_Error ada__io_exceptions__use_error
+extern struct Exception_Data Use_Error;
+
+#define Device_Error ada__io_exceptions__device_error
+extern struct Exception_Data Device_Error;
+
+#define End_Error ada__io_exceptions__end_error
+extern struct Exception_Data End_Error;
+
+#define Data_Error ada__io_exceptions__data_error
+extern struct Exception_Data Data_Error;
+
+#define Layout_Error ada__io_exceptions__layout_error
+extern struct Exception_Data Layout_Error;
+
#define Non_Ada_Error system__aux_dec__non_ada_error
extern struct Exception_Data Non_Ada_Error;
#define Base_Code_In system__vms_exception_table__base_code_in
extern Exception_Code Base_Code_In (Exception_Code);
-#endif
-/* Define macro symbols for the VMS conditions that become Ada exceptions.
- Most of these are also defined in the header file ssdef.h which has not
- yet been converted to be recoginized by Gnu C. Some, which couldn't be
- located, are assigned names based on the DEC test suite tests which
- raise them. */
+/* DEC Ada exceptions are not defined in a header file, so they
+ must be declared as external addresses. */
+
+extern int ADA$_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$_LINEXCMRS, &constraint_error},
+ {0, 0}
+};
-#define SS$_ACCVIO 12
-#define SS$_DEBUG 1132
-#define SS$_INTDIV 1156
-#define SS$_HPARITH 1284
-#define SS$_STKOVF 1364
-#define SS$_RESIGNAL 2328
-#define MTH$_FLOOVEMAT 1475268 /* Some ACVC_21 CXA tests */
-#define SS$_CE24VRU 3253636 /* Write to unopened file */
-#define SS$_C980VTE 3246436 /* AST requests time slice */
-#define CMA$_EXIT_THREAD 4227492
-#define CMA$_EXCCOPLOS 4228108
-#define CMA$_ALERTED 4227460
+#if 0
+ /* Already handled by a pragma Import_Exception
+ in Aux_IO_Exceptions */
+ {&ADA$_LOCK_ERROR, &Lock_Error},
+ {&ADA$_EXISTENCE_ERROR, &Existence_Error},
+ {&ADA$_KEY_ERROR, &Key_Error},
+#endif
-struct descriptor_s {unsigned short len, mbz; char *adr; };
+#endif /* IN_RTS */
-long __gnat_error_handler (int *, void *);
+/* 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$_INTDIV, &constraint_error},
+ {0, 0}
+};
/* To deal with VMS conditions and their mapping to Ada exceptions,
the __gnat_error_handler routine below is installed as an exception
still need to be handled by such handlers, however, in which case
__gnat_error_handler needs to return SS$_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
??? 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 conveniency workaround in the meantime, and
+ 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)
{
- return
- code == CMA$_EXIT_THREAD
- || code == SS$_DEBUG /* Gdb attach, resignal to merge activate gdbstub. */
- || code == 1409786 /* Nickerson bug #33 ??? */
- || code == 1381050 /* Nickerson bug #33 ??? */
- || code == 20480426 /* RDB-E-STREAM_EOF */
- || code == 11829410 /* Resignalled as Use_Error for CE10VRC */
- ;
+ 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$MATCH_COND (&code, &cond_resignal_table [i]));
+ i++);
+
+ return iexcept;
}
/* Static pointer to predicate that the __gnat_error_handler exception
__gnat_resignal_p = predicate;
}
+/* Should match System.Parameters.Default_Exception_Msg_Max_Length. */
+#define Default_Exception_Msg_Max_Length 512
+
+/* Action routine for SYS$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_error_handler (int *sigargs, void *mechargs)
+__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];
- char *msg = "";
- char message[256];
- long prvhnd;
- struct descriptor_s msgdesc;
- int msg_flag = 0x000f; /* 1 bit for each of the four message parts */
- unsigned short outlen;
- char curr_icb[544];
- long curr_invo_handle;
- long *mstate;
+ const char *msg = "";
/* Check for conditions to resignal which aren't effected by pragma
Import_Exception. */
return SS$_RESIGNAL;
#ifdef IN_RTS
- /* See if it's an imported exception. Beware that registered exceptions
+ /* See if it's an imported exception. Beware that registered exceptions
are bound to their base code, with the severity bits masked off. */
base_code = Base_Code_In ((Exception_Code) sigargs [1]);
exception = Coded_Exception (base_code);
if (exception)
{
- msgdesc.len = 256;
- msgdesc.mbz = 0;
- msgdesc.adr = message;
- SYS$GETMSG (sigargs[1], &outlen, &msgdesc, msg_flag, 0);
- message[outlen] = 0;
+ 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. ??? */
+ /* ??? 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$_STKOVF:
exception = &storage_error;
msg = "stack overflow";
- break;
-
- case SS$_INTDIV:
- exception = &constraint_error;
- msg = "division by zero";
+ __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";
- }
-#endif
- break;
-
- case MTH$_FLOOVEMAT:
exception = &constraint_error;
- msg = "floating overflow in math library";
- break;
-
- case SS$_CE24VRU:
- exception = &constraint_error;
- msg = "";
- break;
-
- case SS$_C980VTE:
- exception = &program_error;
- msg = "";
+ msg = "arithmetic error";
+#ifndef __alpha__
+ /* No need to adjust pc on Alpha: the pc is already on the instruction
+ after the trapping one. */
+ __gnat_adjust_context_for_raise (0, (void *)mechargs);
+#endif
+#endif
break;
default:
-#ifndef IN_RTS
- exception = &program_error;
+#ifdef IN_RTS
+ {
+ int i;
+
+ /* Scan the DEC Ada exception condition table for a match and fetch
+ the associated GNAT exception pointer. */
+ for (i = 0;
+ dec_ada_cond_except_table [i].cond &&
+ !LIB$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$MATCH_COND (&sigargs [1], &cond_except_table [i].cond);
+ i++);
+ exception = (struct Exception_Data *)
+ cond_except_table [i].except;
+
+ if (!exception)
+ /* User programs expect Non_Ada_Error to be raised, reference
+ DEC Ada test CXCONDHAN. */
+ exception = &Non_Ada_Error;
+ }
+ }
#else
- /* User programs expect Non_Ada_Error to be raised, reference
- DEC Ada test CXCONDHAN. */
- exception = &Non_Ada_Error;
+ exception = &program_error;
#endif
- msgdesc.len = 256;
- msgdesc.mbz = 0;
- msgdesc.adr = message;
- SYS$GETMSG (sigargs[1], &outlen, &msgdesc, msg_flag, 0);
- message[outlen] = 0;
+ message [0] = 0;
+ /* Subtract PC & PSL fields which messes with PUTMSG. */
+ sigargs [0] -= 2;
+ SYS$PUTMSG (sigargs, copy_msg, &gnat_facility, message);
+ sigargs [0] += 2;
msg = message;
break;
}
- mstate = (long *) (*Get_Machine_State_Addr) ();
- if (mstate != 0)
- {
- lib_get_curr_invo_context (&curr_icb);
- lib_get_prev_invo_context (&curr_icb);
- lib_get_prev_invo_context (&curr_icb);
- curr_invo_handle = lib_get_invo_handle (&curr_icb);
- *mstate = curr_invo_handle;
- }
Raise_From_Signal_Handler (exception, msg);
}
+long
+__gnat_error_handler (int *sigargs, void *mechargs)
+{
+ return __gnat_handle_vms_condition (sigargs, mechargs);
+}
+
void
__gnat_install_handler (void)
{
- long prvhnd;
-#if defined (IN_RTS) && !defined (__IA64)
- char *c;
+ long prvhnd ATTRIBUTE_UNUSED;
- c = (char *) xmalloc (2049);
+#if !defined (IN_RTS)
+ SYS$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$SETEXV (1, __gnat_error_prehandler, 3, &prvhnd);
-#else
- SYS$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_initialize(void *eh ATTRIBUTE_UNUSED)
+__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) ++;
}
-/*************************************************/
-/* __gnat_initialize (FreeBSD version) */
-/*************************************************/
+#endif
+
+/*******************/
+/* 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 *);
+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, 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;
msg = "unhandled signal";
}
+ __gnat_adjust_context_for_raise (sig, ucontext);
Raise_From_Signal_Handler (exception, 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);
(void) sigaction (SIGFPE, &act, NULL);
(void) sigaction (SIGSEGV, &act, NULL);
(void) sigaction (SIGBUS, &act, NULL);
-}
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
- __gnat_install_handler ();
-
- /* XXX - Initialize floating-point coprocessor. This call is
- needed because FreeBSD defaults to 64-bit precision instead
- of 80-bit precision? We require the full precision for
- proper operation, given that we have set Max_Digits etc
- with this in mind */
- __gnat_init_float ();
+ __gnat_handler_installed = 1;
}
-/***************************************/
-/* __gnat_initialize (VXWorks Version) */
-/***************************************/
+/*******************/
+/* 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
+void __gnat_error_handler (int, void *, struct sigcontext *);
+
+#ifndef __RTP__
+
+/* Directly vectored Interrupt routines are not supported when using RTPs. */
+
extern int __gnat_inum_to_ivec (int);
-static void __gnat_error_handler (int, int, struct sigcontext *);
-void __gnat_map_signal (int);
-#ifndef __alpha_vxworks
+/* 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 */
+ on Alpha VxWorks and VxWorks 6.x (including RTPs). */
extern long getpid (void);
}
#endif
-/* This is needed by the GNAT run time to handle Vxworks interrupts */
-int
-__gnat_inum_to_ivec (int num)
-{
- return INUM_TO_IVEC (num);
-}
-
/* 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 */
+ The VxWorks version of longjmp does this; GCC's builtin_longjmp doesn't. */
void
__gnat_clear_exception_count (void)
{
#endif
}
-/* Exported to 5zintman.adb in order to handle different signal
- to exception mappings in different VxWorks versions */
+
+/* VxWorks context adjustment for targets that need/support it. */
+
+void __gnat_adjust_context_for_raise (int, void*);
+
+#if defined (_ARCH_PPC) && !defined (VTHREADS) && !defined (__RTP__)
+
+#define HAVE_GNAT_ADJUST_CONTEXT_FOR_RAISE
+
+/* We need the constant and structure definitions describing the machine
+ state. Part of this is normally retrieved from the VxWorks "regs.h" but
+ #including it here gets the GCC internals instance of this file instead.
+ We need to #include the version we need directly here, and prevent the
+ possibly indirect inclusion of the GCC one, as its contents is useless to
+ us and it depends on several other headers that we don't have at hand. */
+#include <arch/ppc/regsPpc.h>
+#define GCC_REGS_H
+#include <sigLib.h>
+
void
+__gnat_adjust_context_for_raise (int signo ATTRIBUTE_UNUSED, void *sigcontext)
+{
+ REG_SET * mcontext = ((struct sigcontext *) sigcontext)->sc_pregs;
+ mcontext->pc++;
+}
+
+#endif
+
+/* Handle different SIGnal to exception mappings in different VxWorks
+ versions. */
+static void
__gnat_map_signal (int sig)
{
struct Exception_Data *exception;
- char *msg;
+ const char *msg;
switch (sig)
{
msg = "SIGBUS: possible stack overflow";
break;
#else
+#ifdef __RTP__
+ /* In RTP mode a SIGSEGV is most likely due to a stack overflow,
+ since stack checking uses the probing mechanism. */
case SIGILL:
exception = &constraint_error;
msg = "SIGILL";
break;
case SIGSEGV:
+ exception = &storage_error;
+ msg = "SIGSEGV: possible stack overflow";
+ break;
+#else
+ /* In kernel mode 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 = &program_error;
msg = "SIGSEGV";
break;
+#endif
case SIGBUS:
exception = &program_error;
msg = "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_adjust_context_for_raise (sig, (void *)sc);
__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)
asm ("mtfsb0 25");
asm ("mtfsb0 26");
#endif
- /* Similarily 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
}
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
- __gnat_init_float ();
-
- /* On targets where we might be using the ZCX scheme, we need to register
- the frame tables.
-
- For applications loaded as a set of "modules", the crtstuff objects
- linked in (crtbegin/end) are tailored to provide this service a-la C++
- constructor fashion, typically triggered by the VxWorks loader. This is
- achieved by way of a special variable declaration in the crt object, the
- name of which has been deduced by analyzing the output of the "munching"
- step documented for C++. The de-registration is handled symetrically,
- a-la C++ destructor fashion and typically triggered by the dynamic
- unloader. Note that since the tables shall be registered against a
- common datastructure, libgcc should be one of the modules (vs beeing
- partially linked against all the others at build time) and shall be
- loaded first.
-
- For applications linked with the kernel, the scheme above would lead to
- duplicated symbols because the VxWorks kernel build "munches" by default.
- To prevent those conflicts, we link against crtbegin/endS objects that
- don't include the special variable and directly call the appropriate
- function here. We'll never unload that, so there is no de-registration to
- worry about.
-
- For whole applications loaded as a single module, we may use one scheme
- or the other, except for the mixed Ada/C++ case in which the first scheme
- would fail for the same reason as in the linked-with-kernel situation.
-
- We can differentiate by looking at the __module_has_ctors value provided
- by each class of crt objects. As of today, selecting the crt set with the
- ctors/dtors capabilities (first scheme above) is triggered by adding
- "-dynamic" to the gcc *link* command line options. Selecting the other
- set of crt objects is achieved by "-static" instead.
-
- This is a first approach, tightly synchronized with a number of GCC
- configuration and crtstuff changes. We need to ensure that those changes
- are there to activate this circuitry. */
-
-#if (__GNUC__ >= 3) && (defined (_ARCH_PPC) || defined (__ppc))
- {
- /* The scheme described above is only useful for the actual ZCX case, and
- we don't want any reference to the crt provided symbols otherwise. We
- may not link with any of the crt objects in the non-ZCX case, e.g. from
- documented procedures instructing the use of -nostdlib, and references
- to the ctors symbols here would just remain unsatisfied.
-
- We have no way to avoid those references in the right conditions in this
- C module, because we have nothing like a IN_ZCX_RTS macro. This aspect
- is then deferred to an Ada routine, which can do that based on a test
- against a constant System flag value. */
-
- extern void __gnat_vxw_setup_for_eh (void);
- __gnat_vxw_setup_for_eh ();
- }
-#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;
-/********************************/
-/* __gnat_initialize for NetBSD */
-/********************************/
+
+/******************/
+/* NetBSD Section */
+/******************/
#elif defined(__NetBSD__)
act.sa_flags = SA_NODEFER | SA_RESTART;
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 (SIGFPE) != 's')
sigaction (SIGFPE, &act, NULL);
if (__gnat_get_interrupt_state (SIGILL) != 's')
__gnat_handler_installed = 1;
}
-void
-__gnat_initialize (void *eh ATTRIBUTE_UNUSED)
-{
- __gnat_install_handler ();
- __gnat_init_float ();
-}
+/*******************/
+/* OpenBSD Section */
+/*******************/
-#else
+#elif defined(__OpenBSD__)
-/* For all other versions of GNAT, the initialize routine and handler
- installation do nothing */
+#include <signal.h>
+#include <unistd.h>
-/***************************************/
-/* __gnat_initialize (Default Version) */
-/***************************************/
+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_initialize (void *eh ATTRIBUTE_UNUSED)
+__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;
}
-/********************************************/
-/* __gnat_install_handler (Default Version) */
-/********************************************/
+#else
+
+/* For all other versions of GNAT, the handler does nothing. */
+
+/*******************/
+/* Default Section */
+/*******************/
void
__gnat_install_handler (void)
/*********************/
/* 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
#if defined (__i386__) || defined (i386)
/* 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 independant part of the GCC unwinder
- don't differentiate the two situations, so we compensate here for the
- adjustments it will blindly make.
+ /* Adjustments are currently required for the GCC ZCX propagation scheme
+ only. These adjustments (described below) are harmless for the other
+ schemes, so may be applied unconditionally. */
+
+ /* Adjustments required for a GCC ZCX propagation 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. */
+ the unwinder adjustment is still desired.
+
+ We used to perform the compensation 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 this 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. */
}
#endif
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