gdb/i386bsd-tdep.c

/* Target-dependent code for i386 BSD's.

   Copyright (C) 2001, 2002, 2003, 2004, 2007, 2008, 2009, 2010, 2011
   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 "arch-utils.h"
#include "frame.h"
#include "gdbcore.h"
#include "regcache.h"
#include "osabi.h"

#include "gdb_string.h"

#include "i386-tdep.h"

/* Support for signal handlers.  */

/* Assuming THIS_FRAME is for a BSD sigtramp routine, return the
   address of the associated sigcontext structure.  */

static CORE_ADDR
i386bsd_sigcontext_addr (struct frame_info *this_frame)
{
  struct gdbarch *gdbarch = get_frame_arch (this_frame);
  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
  gdb_byte buf[4];
  CORE_ADDR sp;

  get_frame_register (this_frame, I386_ESP_REGNUM, buf);
  sp = extract_unsigned_integer (buf, 4, byte_order);

  return read_memory_unsigned_integer (sp + 8, 4, byte_order);
}


/* Support for shared libraries.  */

/* Traditional BSD (4.3 BSD, still used for BSDI and 386BSD).  */

/* From <machine/signal.h>.  */
int i386bsd_sc_reg_offset[] =
{
  -1,				/* %eax */
  -1,				/* %ecx */
  -1,				/* %edx */
  -1,				/* %ebx */
  8 + 0 * 4,			/* %esp */
  8 + 1 * 4,			/* %ebp */
  -1,				/* %esi */
  -1,				/* %edi */
  8 + 3 * 4,			/* %eip */
  8 + 4 * 4,			/* %eflags */
  -1,				/* %cs */
  -1,				/* %ss */
  -1,				/* %ds */
  -1,				/* %es */
  -1,				/* %fs */
  -1				/* %gs */
};

void
i386bsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);

  tdep->jb_pc_offset = 0;

  tdep->sigtramp_start = 0xfdbfdfc0;
  tdep->sigtramp_end = 0xfdbfe000;
  tdep->sigcontext_addr = i386bsd_sigcontext_addr;
  tdep->sc_reg_offset = i386bsd_sc_reg_offset;
  tdep->sc_num_regs = ARRAY_SIZE (i386bsd_sc_reg_offset);
}


static enum gdb_osabi
i386bsd_aout_osabi_sniffer (bfd *abfd)
{
  if (strcmp (bfd_get_target (abfd), "a.out-i386-netbsd") == 0)
    return GDB_OSABI_NETBSD_AOUT;

  if (strcmp (bfd_get_target (abfd), "a.out-i386-freebsd") == 0)
    return GDB_OSABI_FREEBSD_AOUT;

  return GDB_OSABI_UNKNOWN;
}

static enum gdb_osabi
i386bsd_core_osabi_sniffer (bfd *abfd)
{
  if (strcmp (bfd_get_target (abfd), "netbsd-core") == 0)
    return GDB_OSABI_NETBSD_AOUT;

  return GDB_OSABI_UNKNOWN;
}


/* Provide a prototype to silence -Wmissing-prototypes.  */
void _initialize_i386bsd_tdep (void);

void
_initialize_i386bsd_tdep (void)
{
  gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_aout_flavour,
				  i386bsd_aout_osabi_sniffer);

  /* BFD doesn't set a flavour for NetBSD style a.out core files.  */
  gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_unknown_flavour,
				  i386bsd_core_osabi_sniffer);
}