[deliverable/binutils-gdb.git] / gdb / sparc-nat.c

/* Native-dependent code for SPARC.

   Copyright (C) 2003-2017 Free Software Foundation, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"
#include "inferior.h"
#include "regcache.h"
#include "target.h"

#include <signal.h>
#include <sys/ptrace.h>
#include "gdb_wait.h"
#ifdef HAVE_MACHINE_REG_H
#include <machine/reg.h>
#endif

#include "sparc-tdep.h"
#include "sparc-nat.h"
#include "inf-ptrace.h"

/* With some trickery we can use the code in this file for most (if
   not all) ptrace(2) based SPARC systems, which includes SunOS 4,
   GNU/Linux and the various SPARC BSD's.

   First, we need a data structure for use with ptrace(2).  SunOS has
   `struct regs' and `struct fp_status' in <machine/reg.h>.  BSD's
   have `struct reg' and `struct fpreg' in <machine/reg.h>.  GNU/Linux
   has the same structures as SunOS 4, but they're in <asm/reg.h>,
   which is a kernel header.  As a general rule we avoid including
   GNU/Linux kernel headers.  Fortunately GNU/Linux has a `gregset_t'
   and a `fpregset_t' that are equivalent to `struct regs' and `struct
   fp_status' in <sys/ucontext.h>, which is automatically included by
   <signal.h>.  Settling on using the `gregset_t' and `fpregset_t'
   typedefs, providing them for the other systems, therefore solves
   the puzzle.  */

#ifdef HAVE_MACHINE_REG_H
#ifdef HAVE_STRUCT_REG
typedef struct reg gregset_t;
typedef struct fpreg fpregset_t;
#else 
typedef struct regs gregset_t;
typedef struct fp_status fpregset_t;
#endif
#endif

/* Second, we need to remap the BSD ptrace(2) requests to their SunOS
   equivalents.  GNU/Linux already follows SunOS here.  */

#ifndef PTRACE_GETREGS
#define PTRACE_GETREGS PT_GETREGS
#endif

#ifndef PTRACE_SETREGS
#define PTRACE_SETREGS PT_SETREGS
#endif

#ifndef PTRACE_GETFPREGS
#define PTRACE_GETFPREGS PT_GETFPREGS
#endif

#ifndef PTRACE_SETFPREGS
#define PTRACE_SETFPREGS PT_SETFPREGS
#endif

/* Register set description.  */
const struct sparc_gregmap *sparc_gregmap;
const struct sparc_fpregmap *sparc_fpregmap;
void (*sparc_supply_gregset) (const struct sparc_gregmap *,
			      struct regcache *, int , const void *);
void (*sparc_collect_gregset) (const struct sparc_gregmap *,
			       const struct regcache *, int, void *);
void (*sparc_supply_fpregset) (const struct sparc_fpregmap *,
			       struct regcache *, int , const void *);
void (*sparc_collect_fpregset) (const struct sparc_fpregmap *,
				const struct regcache *, int , void *);
int (*sparc_gregset_supplies_p) (struct gdbarch *, int);
int (*sparc_fpregset_supplies_p) (struct gdbarch *, int);

/* Determine whether `gregset_t' contains register REGNUM.  */

int
sparc32_gregset_supplies_p (struct gdbarch *gdbarch, int regnum)
{
  /* Integer registers.  */
  if ((regnum >= SPARC_G1_REGNUM && regnum <= SPARC_G7_REGNUM)
      || (regnum >= SPARC_O0_REGNUM && regnum <= SPARC_O7_REGNUM)
      || (regnum >= SPARC_L0_REGNUM && regnum <= SPARC_L7_REGNUM)
      || (regnum >= SPARC_I0_REGNUM && regnum <= SPARC_I7_REGNUM))
    return 1;

  /* Control registers.  */
  if (regnum == SPARC32_PC_REGNUM
      || regnum == SPARC32_NPC_REGNUM
      || regnum == SPARC32_PSR_REGNUM
      || regnum == SPARC32_Y_REGNUM)
    return 1;

  return 0;
}

/* Determine whether `fpregset_t' contains register REGNUM.  */

int
sparc32_fpregset_supplies_p (struct gdbarch *gdbarch, int regnum)
{
  /* Floating-point registers.  */
  if (regnum >= SPARC_F0_REGNUM && regnum <= SPARC_F31_REGNUM)
    return 1;

  /* Control registers.  */
  if (regnum == SPARC32_FSR_REGNUM)
    return 1;

  return 0;
}

/* Fetch register REGNUM from the inferior.  If REGNUM is -1, do this
   for all registers (including the floating-point registers).  */

void
sparc_fetch_inferior_registers (struct target_ops *ops,
				struct regcache *regcache, int regnum)
{
  struct gdbarch *gdbarch = regcache->arch ();
  pid_t pid;

  /* NOTE: cagney/2002-12-03: This code assumes that the currently
     selected light weight processes' registers can be written
     directly into the selected thread's register cache.  This works
     fine when given an 1:1 LWP:thread model (such as found on
     GNU/Linux) but will, likely, have problems when used on an N:1
     (userland threads) or N:M (userland multiple LWP) model.  In the
     case of the latter two, the LWP's registers do not necessarily
     belong to the selected thread (the LWP could be in the middle of
     executing the thread switch code).

     These functions should instead be paramaterized with an explicit
     object (struct regcache, struct thread_info?) into which the LWPs
     registers can be written.  */
  pid = get_ptrace_pid (regcache_get_ptid (regcache));

  if (regnum == SPARC_G0_REGNUM)
    {
      gdb_byte zero[8] = { 0 };

      regcache_raw_supply (regcache, SPARC_G0_REGNUM, &zero);
      return;
    }

  if (regnum == -1 || sparc_gregset_supplies_p (gdbarch, regnum))
    {
      gregset_t regs;

      if (ptrace (PTRACE_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
	perror_with_name (_("Couldn't get registers"));

      sparc_supply_gregset (sparc_gregmap, regcache, -1, &regs);
      if (regnum != -1)
	return;
    }

  if (regnum == -1 || sparc_fpregset_supplies_p (gdbarch, regnum))
    {
      fpregset_t fpregs;

      if (ptrace (PTRACE_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
	perror_with_name (_("Couldn't get floating point status"));

      sparc_supply_fpregset (sparc_fpregmap, regcache, -1, &fpregs);
    }
}

void
sparc_store_inferior_registers (struct target_ops *ops,
				struct regcache *regcache, int regnum)
{
  struct gdbarch *gdbarch = regcache->arch ();
  pid_t pid;

  /* NOTE: cagney/2002-12-02: See comment in fetch_inferior_registers
     about threaded assumptions.  */
  pid = get_ptrace_pid (regcache_get_ptid (regcache));

  if (regnum == -1 || sparc_gregset_supplies_p (gdbarch, regnum))
    {
      gregset_t regs;

      if (ptrace (PTRACE_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
	perror_with_name (_("Couldn't get registers"));

      sparc_collect_gregset (sparc_gregmap, regcache, regnum, &regs);

      if (ptrace (PTRACE_SETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
	perror_with_name (_("Couldn't write registers"));

      /* Deal with the stack regs.  */
      if (regnum == -1 || regnum == SPARC_SP_REGNUM
	  || (regnum >= SPARC_L0_REGNUM && regnum <= SPARC_I7_REGNUM))
	{
	  ULONGEST sp;

	  regcache_cooked_read_unsigned (regcache, SPARC_SP_REGNUM, &sp);
	  sparc_collect_rwindow (regcache, sp, regnum);
	}

      if (regnum != -1)
	return;
    }

  if (regnum == -1 || sparc_fpregset_supplies_p (gdbarch, regnum))
    {
      fpregset_t fpregs, saved_fpregs;

      if (ptrace (PTRACE_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
	perror_with_name (_("Couldn't get floating-point registers"));

      memcpy (&saved_fpregs, &fpregs, sizeof (fpregs));
      sparc_collect_fpregset (sparc_fpregmap, regcache, regnum, &fpregs);

      /* Writing the floating-point registers will fail on NetBSD with
	 EINVAL if the inferior process doesn't have an FPU state
	 (i.e. if it didn't use the FPU yet).  Therefore we don't try
	 to write the registers if nothing changed.  */
      if (memcmp (&saved_fpregs, &fpregs, sizeof (fpregs)) != 0)
	{
	  if (ptrace (PTRACE_SETFPREGS, pid,
		      (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
	    perror_with_name (_("Couldn't write floating-point registers"));
	}

      if (regnum != -1)
	return;
    }
}

\f
/* Implement the to_xfer_partial target_ops method for
   TARGET_OBJECT_WCOOKIE.  Fetch StackGhost Per-Process XOR cookie.  */

static enum target_xfer_status
sparc_xfer_wcookie (struct target_ops *ops, enum target_object object,
		    const char *annex, gdb_byte *readbuf,
		    const gdb_byte *writebuf, ULONGEST offset, ULONGEST len,
		    ULONGEST *xfered_len)
{
  unsigned long wcookie = 0;
  char *buf = (char *)&wcookie;

  gdb_assert (object == TARGET_OBJECT_WCOOKIE);
  gdb_assert (readbuf && writebuf == NULL);

  if (offset == sizeof (unsigned long))
    return TARGET_XFER_EOF;			/* Signal EOF.  */
  if (offset > sizeof (unsigned long))
    return TARGET_XFER_E_IO;

#ifdef PT_WCOOKIE
  /* If PT_WCOOKIE is defined (by <sys/ptrace.h>), assume we're
     running on an OpenBSD release that uses StackGhost (3.1 or
     later).  Since release 3.6, OpenBSD uses a fully randomized
     cookie.  */
  {
    int pid = ptid_get_pid (inferior_ptid);

    /* Sanity check.  The proper type for a cookie is register_t, but
       we can't assume that this type exists on all systems supported
       by the code in this file.  */
    gdb_assert (sizeof (wcookie) == sizeof (register_t));

    /* Fetch the cookie.  */
    if (ptrace (PT_WCOOKIE, pid, (PTRACE_TYPE_ARG3) &wcookie, 0) == -1)
      {
	if (errno != EINVAL)
	  perror_with_name (_("Couldn't get StackGhost cookie"));

	/* Although PT_WCOOKIE is defined on OpenBSD 3.1 and later,
	   the request wasn't implemented until after OpenBSD 3.4.  If
	   the kernel doesn't support the PT_WCOOKIE request, assume
	   we're running on a kernel that uses non-randomized cookies.  */
	wcookie = 0x3;
      }
  }
#endif /* PT_WCOOKIE */

  if (len > sizeof (unsigned long) - offset)
    len = sizeof (unsigned long) - offset;

  memcpy (readbuf, buf + offset, len);
  *xfered_len = (ULONGEST) len;
  return TARGET_XFER_OK;
}

target_xfer_partial_ftype *inf_ptrace_xfer_partial;

static enum target_xfer_status
sparc_xfer_partial (struct target_ops *ops, enum target_object object,
		    const char *annex, gdb_byte *readbuf,
		    const gdb_byte *writebuf, ULONGEST offset, ULONGEST len,
		    ULONGEST *xfered_len)
{
  if (object == TARGET_OBJECT_WCOOKIE)
    return sparc_xfer_wcookie (ops, object, annex, readbuf, writebuf, 
			       offset, len, xfered_len);

  return inf_ptrace_xfer_partial (ops, object, annex, readbuf, writebuf,
				  offset, len, xfered_len);
}
\f
/* Create a prototype generic SPARC target.  The client can override
   it with local methods.  */

struct target_ops *
sparc_target (void)
{
  struct target_ops *t;

  t = inf_ptrace_target ();
  t->to_fetch_registers = sparc_fetch_inferior_registers;
  t->to_store_registers = sparc_store_inferior_registers;
  inf_ptrace_xfer_partial = t->to_xfer_partial;
  t->to_xfer_partial = sparc_xfer_partial;
  return t;
}

void
_initialize_sparc_nat (void)
{
  /* Deafult to using SunOS 4 register sets.  */
  if (sparc_gregmap == NULL)
    sparc_gregmap = &sparc32_sunos4_gregmap;
  if (sparc_fpregmap == NULL)
    sparc_fpregmap = &sparc32_sunos4_fpregmap;
  if (sparc_supply_gregset == NULL)
    sparc_supply_gregset = sparc32_supply_gregset;
  if (sparc_collect_gregset == NULL)
    sparc_collect_gregset = sparc32_collect_gregset;
  if (sparc_supply_fpregset == NULL)
    sparc_supply_fpregset = sparc32_supply_fpregset;
  if (sparc_collect_fpregset == NULL)
    sparc_collect_fpregset = sparc32_collect_fpregset;
  if (sparc_gregset_supplies_p == NULL)
    sparc_gregset_supplies_p = sparc32_gregset_supplies_p;
  if (sparc_fpregset_supplies_p == NULL)
    sparc_fpregset_supplies_p = sparc32_fpregset_supplies_p;
}
Commit	Line	Data
	1	/* Native-dependent code for SPARC.
	2
	3	Copyright (C) 2003-2017 Free Software Foundation, Inc.
	4
	5	This file is part of GDB.
	6
	7	This program is free software; you can redistribute it and/or modify
	8	it under the terms of the GNU General Public License as published by
	9	the Free Software Foundation; either version 3 of the License, or
	10	(at your option) any later version.
	11
	12	This program is distributed in the hope that it will be useful,
	13	but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	GNU General Public License for more details.
	16
	17	You should have received a copy of the GNU General Public License
	18	along with this program. If not, see <http://www.gnu.org/licenses/>. */
	19
	20	#include "defs.h"
	21	#include "inferior.h"
	22	#include "regcache.h"
	23	#include "target.h"
	24
	25	#include <signal.h>
	26	#include <sys/ptrace.h>
	27	#include "gdb_wait.h"
	28	#ifdef HAVE_MACHINE_REG_H
	29	#include <machine/reg.h>
	30	#endif
	31
	32	#include "sparc-tdep.h"
	33	#include "sparc-nat.h"
	34	#include "inf-ptrace.h"
	35
	36	/* With some trickery we can use the code in this file for most (if
	37	not all) ptrace(2) based SPARC systems, which includes SunOS 4,
	38	GNU/Linux and the various SPARC BSD's.
	39
	40	First, we need a data structure for use with ptrace(2). SunOS has
	41	`struct regs' and `struct fp_status' in <machine/reg.h>. BSD's
	42	have `struct reg' and `struct fpreg' in <machine/reg.h>. GNU/Linux
	43	has the same structures as SunOS 4, but they're in <asm/reg.h>,
	44	which is a kernel header. As a general rule we avoid including
	45	GNU/Linux kernel headers. Fortunately GNU/Linux has a `gregset_t'
	46	and a `fpregset_t' that are equivalent to `struct regs' and `struct
	47	fp_status' in <sys/ucontext.h>, which is automatically included by
	48	<signal.h>. Settling on using the `gregset_t' and `fpregset_t'
	49	typedefs, providing them for the other systems, therefore solves
	50	the puzzle. */
	51
	52	#ifdef HAVE_MACHINE_REG_H
	53	#ifdef HAVE_STRUCT_REG
	54	typedef struct reg gregset_t;
	55	typedef struct fpreg fpregset_t;
	56	#else
	57	typedef struct regs gregset_t;
	58	typedef struct fp_status fpregset_t;
	59	#endif
	60	#endif
	61
	62	/* Second, we need to remap the BSD ptrace(2) requests to their SunOS
	63	equivalents. GNU/Linux already follows SunOS here. */
	64
	65	#ifndef PTRACE_GETREGS
	66	#define PTRACE_GETREGS PT_GETREGS
	67	#endif
	68
	69	#ifndef PTRACE_SETREGS
	70	#define PTRACE_SETREGS PT_SETREGS
	71	#endif
	72
	73	#ifndef PTRACE_GETFPREGS
	74	#define PTRACE_GETFPREGS PT_GETFPREGS
	75	#endif
	76
	77	#ifndef PTRACE_SETFPREGS
	78	#define PTRACE_SETFPREGS PT_SETFPREGS
	79	#endif
	80
	81	/* Register set description. */
	82	const struct sparc_gregmap *sparc_gregmap;
	83	const struct sparc_fpregmap *sparc_fpregmap;
	84	void (sparc_supply_gregset) (const struct sparc_gregmap ,
	85	struct regcache , int , const void );
	86	void (sparc_collect_gregset) (const struct sparc_gregmap ,
	87	const struct regcache , int, void );
	88	void (sparc_supply_fpregset) (const struct sparc_fpregmap ,
	89	struct regcache , int , const void );
	90	void (sparc_collect_fpregset) (const struct sparc_fpregmap ,
	91	const struct regcache , int , void );
	92	int (sparc_gregset_supplies_p) (struct gdbarch , int);
	93	int (sparc_fpregset_supplies_p) (struct gdbarch , int);
	94
	95	/* Determine whether `gregset_t' contains register REGNUM. */
	96
	97	int
	98	sparc32_gregset_supplies_p (struct gdbarch *gdbarch, int regnum)
	99	{
	100	/* Integer registers. */
	101	if ((regnum >= SPARC_G1_REGNUM && regnum <= SPARC_G7_REGNUM)
	102	\|\| (regnum >= SPARC_O0_REGNUM && regnum <= SPARC_O7_REGNUM)
	103	\|\| (regnum >= SPARC_L0_REGNUM && regnum <= SPARC_L7_REGNUM)
	104	\|\| (regnum >= SPARC_I0_REGNUM && regnum <= SPARC_I7_REGNUM))
	105	return 1;
	106
	107	/* Control registers. */
	108	if (regnum == SPARC32_PC_REGNUM
	109	\|\| regnum == SPARC32_NPC_REGNUM
	110	\|\| regnum == SPARC32_PSR_REGNUM
	111	\|\| regnum == SPARC32_Y_REGNUM)
	112	return 1;
	113
	114	return 0;
	115	}
	116
	117	/* Determine whether `fpregset_t' contains register REGNUM. */
	118
	119	int
	120	sparc32_fpregset_supplies_p (struct gdbarch *gdbarch, int regnum)
	121	{
	122	/* Floating-point registers. */
	123	if (regnum >= SPARC_F0_REGNUM && regnum <= SPARC_F31_REGNUM)
	124	return 1;
	125
	126	/* Control registers. */
	127	if (regnum == SPARC32_FSR_REGNUM)
	128	return 1;
	129
	130	return 0;
	131	}
	132
	133	/* Fetch register REGNUM from the inferior. If REGNUM is -1, do this
	134	for all registers (including the floating-point registers). */
	135
	136	void
	137	sparc_fetch_inferior_registers (struct target_ops *ops,
	138	struct regcache *regcache, int regnum)
	139	{
	140	struct gdbarch *gdbarch = regcache->arch ();
	141	pid_t pid;
	142
	143	/* NOTE: cagney/2002-12-03: This code assumes that the currently
	144	selected light weight processes' registers can be written
	145	directly into the selected thread's register cache. This works
	146	fine when given an 1:1 LWP:thread model (such as found on
	147	GNU/Linux) but will, likely, have problems when used on an N:1
	148	(userland threads) or N:M (userland multiple LWP) model. In the
	149	case of the latter two, the LWP's registers do not necessarily
	150	belong to the selected thread (the LWP could be in the middle of
	151	executing the thread switch code).
	152
	153	These functions should instead be paramaterized with an explicit
	154	object (struct regcache, struct thread_info?) into which the LWPs
	155	registers can be written. */
	156	pid = get_ptrace_pid (regcache_get_ptid (regcache));
	157
	158	if (regnum == SPARC_G0_REGNUM)
	159	{
	160	gdb_byte zero[8] = { 0 };
	161
	162	regcache_raw_supply (regcache, SPARC_G0_REGNUM, &zero);
	163	return;
	164	}
	165
	166	if (regnum == -1 \|\| sparc_gregset_supplies_p (gdbarch, regnum))
	167	{
	168	gregset_t regs;
	169
	170	if (ptrace (PTRACE_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
	171	perror_with_name (_("Couldn't get registers"));
	172
	173	sparc_supply_gregset (sparc_gregmap, regcache, -1, &regs);
	174	if (regnum != -1)
	175	return;
	176	}
	177
	178	if (regnum == -1 \|\| sparc_fpregset_supplies_p (gdbarch, regnum))
	179	{
	180	fpregset_t fpregs;
	181
	182	if (ptrace (PTRACE_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
	183	perror_with_name (_("Couldn't get floating point status"));
	184
	185	sparc_supply_fpregset (sparc_fpregmap, regcache, -1, &fpregs);
	186	}
	187	}
	188
	189	void
	190	sparc_store_inferior_registers (struct target_ops *ops,
	191	struct regcache *regcache, int regnum)
	192	{
	193	struct gdbarch *gdbarch = regcache->arch ();
	194	pid_t pid;
	195
	196	/* NOTE: cagney/2002-12-02: See comment in fetch_inferior_registers
	197	about threaded assumptions. */
	198	pid = get_ptrace_pid (regcache_get_ptid (regcache));
	199
	200	if (regnum == -1 \|\| sparc_gregset_supplies_p (gdbarch, regnum))
	201	{
	202	gregset_t regs;
	203
	204	if (ptrace (PTRACE_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
	205	perror_with_name (_("Couldn't get registers"));
	206
	207	sparc_collect_gregset (sparc_gregmap, regcache, regnum, &regs);
	208
	209	if (ptrace (PTRACE_SETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
	210	perror_with_name (_("Couldn't write registers"));
	211
	212	/* Deal with the stack regs. */
	213	if (regnum == -1 \|\| regnum == SPARC_SP_REGNUM
	214	\|\| (regnum >= SPARC_L0_REGNUM && regnum <= SPARC_I7_REGNUM))
	215	{
	216	ULONGEST sp;
	217
	218	regcache_cooked_read_unsigned (regcache, SPARC_SP_REGNUM, &sp);
	219	sparc_collect_rwindow (regcache, sp, regnum);
	220	}
	221
	222	if (regnum != -1)
	223	return;
	224	}
	225
	226	if (regnum == -1 \|\| sparc_fpregset_supplies_p (gdbarch, regnum))
	227	{
	228	fpregset_t fpregs, saved_fpregs;
	229
	230	if (ptrace (PTRACE_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
	231	perror_with_name (_("Couldn't get floating-point registers"));
	232
	233	memcpy (&saved_fpregs, &fpregs, sizeof (fpregs));
	234	sparc_collect_fpregset (sparc_fpregmap, regcache, regnum, &fpregs);
	235
	236	/* Writing the floating-point registers will fail on NetBSD with
	237	EINVAL if the inferior process doesn't have an FPU state
	238	(i.e. if it didn't use the FPU yet). Therefore we don't try
	239	to write the registers if nothing changed. */
	240	if (memcmp (&saved_fpregs, &fpregs, sizeof (fpregs)) != 0)
	241	{
	242	if (ptrace (PTRACE_SETFPREGS, pid,
	243	(PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
	244	perror_with_name (_("Couldn't write floating-point registers"));
	245	}
	246
	247	if (regnum != -1)
	248	return;
	249	}
	250	}
	251
	252	\f
	253	/* Implement the to_xfer_partial target_ops method for
	254	TARGET_OBJECT_WCOOKIE. Fetch StackGhost Per-Process XOR cookie. */
	255
	256	static enum target_xfer_status
	257	sparc_xfer_wcookie (struct target_ops *ops, enum target_object object,
	258	const char annex, gdb_byte readbuf,
	259	const gdb_byte *writebuf, ULONGEST offset, ULONGEST len,
	260	ULONGEST *xfered_len)
	261	{
	262	unsigned long wcookie = 0;
	263	char buf = (char )&wcookie;
	264
	265	gdb_assert (object == TARGET_OBJECT_WCOOKIE);
	266	gdb_assert (readbuf && writebuf == NULL);
	267
	268	if (offset == sizeof (unsigned long))
	269	return TARGET_XFER_EOF; /* Signal EOF. */
	270	if (offset > sizeof (unsigned long))
	271	return TARGET_XFER_E_IO;
	272
	273	#ifdef PT_WCOOKIE
	274	/* If PT_WCOOKIE is defined (by <sys/ptrace.h>), assume we're
	275	running on an OpenBSD release that uses StackGhost (3.1 or
	276	later). Since release 3.6, OpenBSD uses a fully randomized
	277	cookie. */
	278	{
	279	int pid = ptid_get_pid (inferior_ptid);
	280
	281	/* Sanity check. The proper type for a cookie is register_t, but
	282	we can't assume that this type exists on all systems supported
	283	by the code in this file. */
	284	gdb_assert (sizeof (wcookie) == sizeof (register_t));
	285
	286	/* Fetch the cookie. */
	287	if (ptrace (PT_WCOOKIE, pid, (PTRACE_TYPE_ARG3) &wcookie, 0) == -1)
	288	{
	289	if (errno != EINVAL)
	290	perror_with_name (_("Couldn't get StackGhost cookie"));
	291
	292	/* Although PT_WCOOKIE is defined on OpenBSD 3.1 and later,
	293	the request wasn't implemented until after OpenBSD 3.4. If
	294	the kernel doesn't support the PT_WCOOKIE request, assume
	295	we're running on a kernel that uses non-randomized cookies. */
	296	wcookie = 0x3;
	297	}
	298	}
	299	#endif /* PT_WCOOKIE */
	300
	301	if (len > sizeof (unsigned long) - offset)
	302	len = sizeof (unsigned long) - offset;
	303
	304	memcpy (readbuf, buf + offset, len);
	305	*xfered_len = (ULONGEST) len;
	306	return TARGET_XFER_OK;
	307	}
	308
	309	target_xfer_partial_ftype *inf_ptrace_xfer_partial;
	310
	311	static enum target_xfer_status
	312	sparc_xfer_partial (struct target_ops *ops, enum target_object object,
	313	const char annex, gdb_byte readbuf,
	314	const gdb_byte *writebuf, ULONGEST offset, ULONGEST len,
	315	ULONGEST *xfered_len)
	316	{
	317	if (object == TARGET_OBJECT_WCOOKIE)
	318	return sparc_xfer_wcookie (ops, object, annex, readbuf, writebuf,
	319	offset, len, xfered_len);
	320
	321	return inf_ptrace_xfer_partial (ops, object, annex, readbuf, writebuf,
	322	offset, len, xfered_len);
	323	}
	324	\f
	325	/* Create a prototype generic SPARC target. The client can override
	326	it with local methods. */
	327
	328	struct target_ops *
	329	sparc_target (void)
	330	{
	331	struct target_ops *t;
	332
	333	t = inf_ptrace_target ();
	334	t->to_fetch_registers = sparc_fetch_inferior_registers;
	335	t->to_store_registers = sparc_store_inferior_registers;
	336	inf_ptrace_xfer_partial = t->to_xfer_partial;
	337	t->to_xfer_partial = sparc_xfer_partial;
	338	return t;
	339	}
	340
	341	void
	342	_initialize_sparc_nat (void)
	343	{
	344	/* Deafult to using SunOS 4 register sets. */
	345	if (sparc_gregmap == NULL)
	346	sparc_gregmap = &sparc32_sunos4_gregmap;
	347	if (sparc_fpregmap == NULL)
	348	sparc_fpregmap = &sparc32_sunos4_fpregmap;
	349	if (sparc_supply_gregset == NULL)
	350	sparc_supply_gregset = sparc32_supply_gregset;
	351	if (sparc_collect_gregset == NULL)
	352	sparc_collect_gregset = sparc32_collect_gregset;
	353	if (sparc_supply_fpregset == NULL)
	354	sparc_supply_fpregset = sparc32_supply_fpregset;
	355	if (sparc_collect_fpregset == NULL)
	356	sparc_collect_fpregset = sparc32_collect_fpregset;
	357	if (sparc_gregset_supplies_p == NULL)
	358	sparc_gregset_supplies_p = sparc32_gregset_supplies_p;
	359	if (sparc_fpregset_supplies_p == NULL)
	360	sparc_fpregset_supplies_p = sparc32_fpregset_supplies_p;
	361	}