* *
* C Implementation File *
* *
- * Copyright (C) 1992-2007, 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- *
* *
****************************************************************************/
-/* 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
extern void __gnat_raise_program_error (const char *, int);
-/* Addresses of exception data blocks for predefined exceptions. Tasking_Error
- is not used in this unit, and the abort signal is only used on IRIX. */
+/* Addresses of exception data blocks for predefined exceptions. Tasking_Error
+ is not used in this unit, and the abort signal is only used on IRIX. */
extern struct Exception_Data constraint_error;
extern struct Exception_Data numeric_error;
extern struct Exception_Data program_error;
extern struct Exception_Data storage_error;
/* For the Cert run time we use the regular raise exception routine because
- Raise_From_Signal_Handler is not available. */
+ 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 *);
#endif
-/* Global values computed by the binder */
+/* Global values computed by the binder. */
int __gl_main_priority = -1;
int __gl_time_slice_val = -1;
char __gl_wc_encoding = 'n';
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). */
+ 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)
char __gnat_get_specific_dispatching (int);
-/* This routine is called from the run time as needed to determine the
+/* 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
+ 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. */
+ Priority_Specific_Dispatching pragma is used in the partition. */
char
__gnat_get_specific_dispatching (int priority)
/* __gnat_set_globals */
/**********************/
-/* This routine is kept for boostrapping purposes, since the binder generated
- file now sets the __gl_* variables directly. */
+/* This routine is kept for bootstrapping purposes, since the binder generated
+ file now sets the __gl_* variables directly. */
void
__gnat_set_globals ()
#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
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_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')
/* 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')
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;
}
/*********************/
#elif defined (linux) && (defined (i386) || defined (__x86_64__) \
- || defined (__ia64__))
+ || defined (__ia64__) || defined (__powerpc__))
#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)
#if defined (MaRTE)
/* MaRTE OS provides its own version of sigaction, sigfillset, and
- sigemptyset (overriding these symbol names). We want to make sure that
+ 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
+ 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. */
+ defined within the C library. */
#pragma weak linux_sigaction
int linux_sigaction (int signum, const struct sigaction *act,
void
__gnat_adjust_context_for_raise (int signo ATTRIBUTE_UNUSED, void *ucontext)
{
+#ifndef __powerpc__
mcontext_t *mcontext = &((ucontext_t *) ucontext)->uc_mcontext;
+#endif
+
+ /* 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
}
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;
/* 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. */
+ POSIX Thread Library (NPTL) are compiled with DWARF-2 unwind information,
+ and hence the later macro is never executed for signal frames. */
__gnat_adjust_context_for_raise (sig, ucontext);
Raise_From_Signal_Handler (exception, msg);
}
+#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. */
+
+#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);
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')
}
/*******************/
+/* LynxOS Section */
+/*******************/
+
+#elif defined (__Lynx__)
+
+#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 = 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 */
/*******************/
#include <sys/ucontext.h>
#include <sys/regset.h>
-/* The code below is common to sparc and x86. Beware of the delay slot
+/* The code below is common to SPARC and x86. Beware of the delay slot
differences for signal context adjustments. */
#if defined (__sparc)
/* 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. */
+ or "PC" at hand, depending on the target CPU and Solaris version. */
#if !defined (REG_PC)
#define REG_PC PC
/* 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')
#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$_RESIGNAL 2328
-/* These codes are in standard message libraries */
+/* These codes are in standard message libraries. */
extern int CMA$_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 */
+ must be declared as external addresses. */
extern int ADA$_PROGRAM_ERROR;
extern int ADA$_LOCK_ERROR;
extern int ADA$_MAXLINEXC;
extern int ADA$_LINEXCMRS;
-/* DEC Ada specific conditions */
+/* 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$_RESIGNAL. Consider for
instance the use of a third party library compiled with DECAda and
- performing it's own exception handling internally.
+ performing its own exception handling internally.
To allow some user-level flexibility, which conditions should be
resignaled is controlled by a predicate function, provided with the
__gnat_resignal_p = predicate;
}
-/* Should match System.Parameters.Default_Exception_Msg_Max_Length */
+/* Should match System.Parameters.Default_Exception_Msg_Max_Length. */
#define Default_Exception_Msg_Max_Length 512
-/* Action routine for SYS$PUTMSG. There may be
- multiple conditions, each with text to be appended to
- MESSAGE and separated by line termination. */
+/* Action routine for SYS$PUTMSG. There may be multiple
+ conditions, each with text to be appended to MESSAGE
+ and separated by line termination. */
static int
copy_msg (msgdesc, message)
int len = strlen (message);
int copy_len;
- /* Check for buffer overflow and skip */
+ /* Check for buffer overflow and skip. */
if (len > 0 && len <= Default_Exception_Msg_Max_Length - 3)
{
strcat (message, "\r\n");
len += 2;
}
- /* Check for buffer overflow and truncate if necessary */
+ /* Check for buffer overflow and truncate if necessary. */
copy_len = (len + msgdesc->len <= Default_Exception_Msg_Max_Length - 1 ?
msgdesc->len :
Default_Exception_Msg_Max_Length - 1 - len);
return SS$_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$getmsg returns. */
exception->Full_Name = "IMPORTED_EXCEPTION";
exception->Import_Code = base_code;
#else
exception = &constraint_error;
msg = "arithmetic error";
+#ifndef __alpha__
+ /* No need to adjust pc on Alpha: the pc is already on the instruction
+ after the trapping one. */
__gnat_adjust_context_for_raise (0, (void *)mechargs);
#endif
+#endif
break;
default:
int i;
/* Scan the DEC Ada exception condition table for a match and fetch
- the associated GNAT exception pointer */
+ the associated GNAT exception pointer. */
for (i = 0;
dec_ada_cond_except_table [i].cond &&
!LIB$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$MATCH_COND (&sigargs [1], &cond_except_table [i].cond);
if (!exception)
/* User programs expect Non_Ada_Error to be raised, reference
- DEC Ada test CXCONDHAN. */
+ DEC Ada test CXCONDHAN. */
exception = &Non_Ada_Error;
}
}
exception = &program_error;
#endif
message [0] = 0;
- /* Subtract PC & PSL fields which messes with PUTMSG */
+ /* Subtract PC & PSL fields which messes with PUTMSG. */
sigargs [0] -= 2;
SYS$PUTMSG (sigargs, copy_msg, &gnat_facility, message);
sigargs [0] += 2;
__gnat_handler_installed = 1;
}
-/* __gnat_adjust_context_for_raise for alpha - see comments along with the
+/* __gnat_adjust_context_for_raise for Alpha - see comments along with the
default version later in this file. */
#if defined (IN_RTS) && defined (__alpha__)
/* 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_sigaction
= (void (*)(int, struct __siginfo *, void*)) __gnat_error_handler;
#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 */
+ 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 */
+
+/* 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;
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;
-/* In RTP mode a SIGSEGV is most likely due to a stack overflow. This is not
- the case in kernel mode where stack overflow detection uses a comparison
- method instead of memory probes. */
-#ifdef __RTP__
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";
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");
#if (defined (__i386__) || defined (i386)) && !defined (VTHREADS)
/* This is used to properly initialize the FPU on an x86 for each
- process thread. */
+ process thread. */
asm ("finit");
#endif
- /* Similarly for sparc64. Achieved by masking bits in the Trap Enable Mask
+ /* 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);
#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
#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. */
/* Given UCONTEXT a pointer to a context structure received by a signal
handler for SIGNO, perform the necessary adjustments to let the handler
OSDN Git Service
