/* Mach-O support for BFD.
   Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005
   Free Software Foundation, Inc.

   This file is part of BFD, the Binary File Descriptor library.

   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 2 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, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#include "mach-o.h"
#include "bfd.h"
#include "sysdep.h"
#include "libbfd.h"
#include "libiberty.h"
#include <ctype.h>

#ifndef BFD_IO_FUNCS
#define BFD_IO_FUNCS 0
#endif

#define bfd_mach_o_mkarchive _bfd_noarchive_mkarchive
#define bfd_mach_o_read_ar_hdr _bfd_noarchive_read_ar_hdr
#define bfd_mach_o_slurp_armap _bfd_noarchive_slurp_armap
#define bfd_mach_o_slurp_extended_name_table _bfd_noarchive_slurp_extended_name_table
#define bfd_mach_o_construct_extended_name_table _bfd_noarchive_construct_extended_name_table
#define bfd_mach_o_truncate_arname _bfd_noarchive_truncate_arname
#define bfd_mach_o_write_armap _bfd_noarchive_write_armap
#define bfd_mach_o_get_elt_at_index _bfd_noarchive_get_elt_at_index
#define bfd_mach_o_generic_stat_arch_elt _bfd_noarchive_generic_stat_arch_elt
#define bfd_mach_o_update_armap_timestamp _bfd_noarchive_update_armap_timestamp
#define	bfd_mach_o_close_and_cleanup _bfd_generic_close_and_cleanup
#define bfd_mach_o_bfd_free_cached_info _bfd_generic_bfd_free_cached_info
#define bfd_mach_o_new_section_hook _bfd_generic_new_section_hook
#define bfd_mach_o_get_section_contents_in_window _bfd_generic_get_section_contents_in_window
#define bfd_mach_o_bfd_is_local_label_name _bfd_nosymbols_bfd_is_local_label_name
#define bfd_mach_o_bfd_is_target_special_symbol ((bfd_boolean (*) (bfd *, asymbol *)) bfd_false)
#define bfd_mach_o_bfd_is_local_label_name _bfd_nosymbols_bfd_is_local_label_name
#define bfd_mach_o_get_lineno _bfd_nosymbols_get_lineno
#define bfd_mach_o_find_nearest_line _bfd_nosymbols_find_nearest_line
#define bfd_mach_o_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol
#define bfd_mach_o_read_minisymbols _bfd_generic_read_minisymbols
#define bfd_mach_o_minisymbol_to_symbol _bfd_generic_minisymbol_to_symbol
#define bfd_mach_o_get_reloc_upper_bound _bfd_norelocs_get_reloc_upper_bound
#define bfd_mach_o_canonicalize_reloc _bfd_norelocs_canonicalize_reloc
#define bfd_mach_o_bfd_reloc_type_lookup _bfd_norelocs_bfd_reloc_type_lookup
#define bfd_mach_o_bfd_get_relocated_section_contents bfd_generic_get_relocated_section_contents
#define bfd_mach_o_bfd_relax_section bfd_generic_relax_section
#define bfd_mach_o_bfd_link_hash_table_create _bfd_generic_link_hash_table_create
#define bfd_mach_o_bfd_link_hash_table_free _bfd_generic_link_hash_table_free
#define bfd_mach_o_bfd_link_add_symbols _bfd_generic_link_add_symbols
#define bfd_mach_o_bfd_link_just_syms _bfd_generic_link_just_syms
#define bfd_mach_o_bfd_final_link _bfd_generic_final_link
#define bfd_mach_o_bfd_link_split_section _bfd_generic_link_split_section
#define bfd_mach_o_set_arch_mach bfd_default_set_arch_mach
#define bfd_mach_o_bfd_merge_private_bfd_data _bfd_generic_bfd_merge_private_bfd_data
#define bfd_mach_o_bfd_set_private_flags _bfd_generic_bfd_set_private_flags
#define bfd_mach_o_bfd_print_private_bfd_data _bfd_generic_bfd_print_private_bfd_data
#define bfd_mach_o_get_section_contents _bfd_generic_get_section_contents
#define bfd_mach_o_set_section_contents _bfd_generic_set_section_contents
#define bfd_mach_o_bfd_gc_sections bfd_generic_gc_sections
#define bfd_mach_o_bfd_merge_sections bfd_generic_merge_sections
#define bfd_mach_o_bfd_is_group_section bfd_generic_is_group_section
#define bfd_mach_o_bfd_discard_group bfd_generic_discard_group
#define bfd_mach_o_section_already_linked \
  _bfd_generic_section_already_linked
#define bfd_mach_o_bfd_copy_private_header_data _bfd_generic_bfd_copy_private_header_data

static bfd_boolean bfd_mach_o_bfd_copy_private_symbol_data
  PARAMS ((bfd *, asymbol *, bfd *, asymbol *));
static bfd_boolean bfd_mach_o_bfd_copy_private_section_data
  PARAMS ((bfd *, asection *, bfd *, asection *));
static bfd_boolean bfd_mach_o_bfd_copy_private_bfd_data
  PARAMS ((bfd *, bfd *));
static long bfd_mach_o_count_symbols
  PARAMS ((bfd *));
static long bfd_mach_o_get_symtab_upper_bound
  PARAMS ((bfd *));
static long bfd_mach_o_canonicalize_symtab
  PARAMS ((bfd *, asymbol **));
static void bfd_mach_o_get_symbol_info
  PARAMS ((bfd *, asymbol *, symbol_info *));
static void bfd_mach_o_print_symbol
  PARAMS ((bfd *, PTR, asymbol *, bfd_print_symbol_type));
static void bfd_mach_o_convert_architecture
  PARAMS ((bfd_mach_o_cpu_type, bfd_mach_o_cpu_subtype,
	   enum bfd_architecture *, unsigned long *));
static bfd_boolean bfd_mach_o_write_contents
  PARAMS ((bfd *));
static int bfd_mach_o_sizeof_headers
  PARAMS ((bfd *, bfd_boolean));
static asymbol * bfd_mach_o_make_empty_symbol
  PARAMS ((bfd *));
static int bfd_mach_o_write_header
  PARAMS ((bfd *, bfd_mach_o_header *));
static int bfd_mach_o_read_header
  PARAMS ((bfd *, bfd_mach_o_header *));
static asection * bfd_mach_o_make_bfd_section
  PARAMS ((bfd *, bfd_mach_o_section *));
static int bfd_mach_o_scan_read_section
  PARAMS ((bfd *, bfd_mach_o_section *, bfd_vma));
static int bfd_mach_o_scan_write_section
  PARAMS ((bfd *, bfd_mach_o_section *, bfd_vma));
static int bfd_mach_o_scan_write_symtab_symbols
  PARAMS ((bfd *, bfd_mach_o_load_command *));
static int bfd_mach_o_scan_write_thread
  PARAMS ((bfd *, bfd_mach_o_load_command *));
static int bfd_mach_o_scan_read_dylinker
  PARAMS ((bfd *, bfd_mach_o_load_command *));
static int bfd_mach_o_scan_read_dylib
  PARAMS ((bfd *, bfd_mach_o_load_command *));
static int bfd_mach_o_scan_read_prebound_dylib
  PARAMS ((bfd *, bfd_mach_o_load_command *));
static int bfd_mach_o_scan_read_thread
  PARAMS ((bfd *, bfd_mach_o_load_command *));
static int bfd_mach_o_scan_write_symtab
  PARAMS ((bfd *, bfd_mach_o_load_command *));
static int bfd_mach_o_scan_read_dysymtab
  PARAMS ((bfd *, bfd_mach_o_load_command *));
static int bfd_mach_o_scan_read_symtab
  PARAMS ((bfd *, bfd_mach_o_load_command *));
static int bfd_mach_o_scan_read_segment
  PARAMS ((bfd *, bfd_mach_o_load_command *));
static int bfd_mach_o_scan_write_segment
  PARAMS ((bfd *, bfd_mach_o_load_command *));
static int bfd_mach_o_scan_read_command
  PARAMS ((bfd *, bfd_mach_o_load_command *));
static void bfd_mach_o_flatten_sections
  PARAMS ((bfd *));
static const char * bfd_mach_o_i386_flavour_string
  PARAMS ((unsigned int));
static const char * bfd_mach_o_ppc_flavour_string
  PARAMS ((unsigned int));

/* The flags field of a section structure is separated into two parts a section
   type and section attributes.  The section types are mutually exclusive (it
   can only have one type) but the section attributes are not (it may have more
   than one attribute).  */

#define SECTION_TYPE             0x000000ff     /* 256 section types.  */
#define SECTION_ATTRIBUTES       0xffffff00     /*  24 section attributes.  */

/* Constants for the section attributes part of the flags field of a section
   structure.  */

#define SECTION_ATTRIBUTES_USR   0xff000000     /* User-settable attributes.  */
#define S_ATTR_PURE_INSTRUCTIONS 0x80000000     /* Section contains only true machine instructions.  */
#define SECTION_ATTRIBUTES_SYS   0x00ffff00     /* System setable attributes.  */
#define S_ATTR_SOME_INSTRUCTIONS 0x00000400     /* Section contains some machine instructions.  */
#define S_ATTR_EXT_RELOC         0x00000200     /* Section has external relocation entries.  */
#define S_ATTR_LOC_RELOC         0x00000100     /* Section has local relocation entries.  */

#define N_STAB 0xe0
#define N_TYPE 0x1e
#define N_EXT  0x01
#define N_UNDF 0x0
#define N_ABS  0x2
#define N_SECT 0xe
#define N_INDR 0xa

bfd_boolean
bfd_mach_o_valid (abfd)
     bfd *abfd;
{
  if (abfd == NULL || abfd->xvec == NULL)
    return 0;

  if (! ((abfd->xvec == &mach_o_be_vec)
	 || (abfd->xvec == &mach_o_le_vec)
	 || (abfd->xvec == &mach_o_fat_vec)))
    return 0;

  if (abfd->tdata.mach_o_data == NULL)
    return 0;
  return 1;
}

/* Copy any private info we understand from the input symbol
   to the output symbol.  */

static bfd_boolean
bfd_mach_o_bfd_copy_private_symbol_data (ibfd, isymbol, obfd, osymbol)
     bfd *ibfd ATTRIBUTE_UNUSED;
     asymbol *isymbol ATTRIBUTE_UNUSED;
     bfd *obfd ATTRIBUTE_UNUSED;
     asymbol *osymbol ATTRIBUTE_UNUSED;
{
  return TRUE;
}

/* Copy any private info we understand from the input section
   to the output section.  */

static bfd_boolean
bfd_mach_o_bfd_copy_private_section_data (ibfd, isection, obfd, osection)
     bfd *ibfd ATTRIBUTE_UNUSED;
     asection *isection ATTRIBUTE_UNUSED;
     bfd *obfd ATTRIBUTE_UNUSED;
     asection *osection ATTRIBUTE_UNUSED;
{
  return TRUE;
}

/* Copy any private info we understand from the input bfd
   to the output bfd.  */

static bfd_boolean
bfd_mach_o_bfd_copy_private_bfd_data (ibfd, obfd)
     bfd *ibfd;
     bfd *obfd;
{
  BFD_ASSERT (bfd_mach_o_valid (ibfd));
  BFD_ASSERT (bfd_mach_o_valid (obfd));

  obfd->tdata.mach_o_data = ibfd->tdata.mach_o_data;
  obfd->tdata.mach_o_data->ibfd = ibfd;
  return TRUE;
}

static long
bfd_mach_o_count_symbols (abfd)
     bfd *abfd;
{
  bfd_mach_o_data_struct *mdata = NULL;
  long nsyms = 0;
  unsigned long i;

  BFD_ASSERT (bfd_mach_o_valid (abfd));
  mdata = abfd->tdata.mach_o_data;

  for (i = 0; i < mdata->header.ncmds; i++)
    if (mdata->commands[i].type == BFD_MACH_O_LC_SYMTAB)
      {
	bfd_mach_o_symtab_command *sym = &mdata->commands[i].command.symtab;
	nsyms += sym->nsyms;
      }

  return nsyms;
}

static long
bfd_mach_o_get_symtab_upper_bound (abfd)
     bfd *abfd;
{
  long nsyms = bfd_mach_o_count_symbols (abfd);

  if (nsyms < 0)
    return nsyms;

  return ((nsyms + 1) * sizeof (asymbol *));
}

static long
bfd_mach_o_canonicalize_symtab (abfd, alocation)
     bfd *abfd;
     asymbol **alocation;
{
  bfd_mach_o_data_struct *mdata = abfd->tdata.mach_o_data;
  long nsyms = bfd_mach_o_count_symbols (abfd);
  asymbol **csym = alocation;
  unsigned long i, j;

  if (nsyms < 0)
    return nsyms;

  for (i = 0; i < mdata->header.ncmds; i++)
    {
      if (mdata->commands[i].type == BFD_MACH_O_LC_SYMTAB)
	{
	  bfd_mach_o_symtab_command *sym = &mdata->commands[i].command.symtab;

	  if (bfd_mach_o_scan_read_symtab_symbols (abfd, &mdata->commands[i].command.symtab) != 0)
	    {
	      fprintf (stderr, "bfd_mach_o_canonicalize_symtab: unable to load symbols for section %lu\n", i);
	      return 0;
	    }

	  BFD_ASSERT (sym->symbols != NULL);

	  for (j = 0; j < sym->nsyms; j++)
	    {
	      BFD_ASSERT (csym < (alocation + nsyms));
	      *csym++ = &sym->symbols[j];
	    }
	}
    }

  *csym++ = NULL;

  return nsyms;
}

static void
bfd_mach_o_get_symbol_info (abfd, symbol, ret)
     bfd *abfd ATTRIBUTE_UNUSED;
     asymbol *symbol;
     symbol_info *ret;
{
  bfd_symbol_info (symbol, ret);
}

static void
bfd_mach_o_print_symbol (abfd, afile, symbol, how)
     bfd *abfd;
     PTR afile;
     asymbol *symbol;
     bfd_print_symbol_type how;
{
  FILE *file = (FILE *) afile;

  switch (how)
    {
    case bfd_print_symbol_name:
      fprintf (file, "%s", symbol->name);
      break;
    default:
      bfd_print_symbol_vandf (abfd, (PTR) file, symbol);
      fprintf (file, " %-5s %s", symbol->section->name, symbol->name);
    }
}

static void
bfd_mach_o_convert_architecture (mtype, msubtype, type, subtype)
     bfd_mach_o_cpu_type mtype;
     bfd_mach_o_cpu_subtype msubtype ATTRIBUTE_UNUSED;
     enum bfd_architecture *type;
     unsigned long *subtype;
{
  *subtype = bfd_arch_unknown;

  switch (mtype)
    {
    case BFD_MACH_O_CPU_TYPE_VAX: *type = bfd_arch_vax; break;
    case BFD_MACH_O_CPU_TYPE_MC680x0: *type = bfd_arch_m68k; break;
    case BFD_MACH_O_CPU_TYPE_I386: *type = bfd_arch_i386; break;
    case BFD_MACH_O_CPU_TYPE_MIPS: *type = bfd_arch_mips; break;
    case BFD_MACH_O_CPU_TYPE_MC98000: *type = bfd_arch_m98k; break;
    case BFD_MACH_O_CPU_TYPE_HPPA: *type = bfd_arch_hppa; break;
    case BFD_MACH_O_CPU_TYPE_ARM: *type = bfd_arch_arm; break;
    case BFD_MACH_O_CPU_TYPE_MC88000: *type = bfd_arch_m88k; break;
    case BFD_MACH_O_CPU_TYPE_SPARC: *type = bfd_arch_sparc; break;
    case BFD_MACH_O_CPU_TYPE_I860: *type = bfd_arch_i860; break;
    case BFD_MACH_O_CPU_TYPE_ALPHA: *type = bfd_arch_alpha; break;
    case BFD_MACH_O_CPU_TYPE_POWERPC: *type = bfd_arch_powerpc; break;
    default: *type = bfd_arch_unknown; break;
    }

  switch (*type)
    {
    case bfd_arch_i386: *subtype = bfd_mach_i386_i386; break;
    case bfd_arch_sparc: *subtype = bfd_mach_sparc; break;
    default:
      *subtype = bfd_arch_unknown;
    }
}

static bfd_boolean
bfd_mach_o_write_contents (abfd)
     bfd *abfd;
{
  unsigned int i;
  asection *s;

  bfd_mach_o_data_struct *mdata = abfd->tdata.mach_o_data;

  /* Write data sections first in case they overlap header data to be
     written later.  */

  for (s = abfd->sections; s != (asection *) NULL; s = s->next)
    ;

  /* Now write header information.  */
  if (bfd_mach_o_write_header (abfd, &mdata->header) != 0)
    return FALSE;

  for (i = 0; i < mdata->header.ncmds; i++)
    {
      unsigned char buf[8];
      bfd_mach_o_load_command *cur = &mdata->commands[i];
      unsigned long typeflag;

      typeflag = cur->type_required ? cur->type & BFD_MACH_O_LC_REQ_DYLD : cur->type;

      bfd_h_put_32 (abfd, typeflag, buf);
      bfd_h_put_32 (abfd, cur->len, buf + 4);

      bfd_seek (abfd, cur->offset, SEEK_SET);
      if (bfd_bwrite ((PTR) buf, 8, abfd) != 8)
	return FALSE;

      switch (cur->type)
	{
	case BFD_MACH_O_LC_SEGMENT:
	  if (bfd_mach_o_scan_write_segment (abfd, cur) != 0)
	    return FALSE;
	  break;
	case BFD_MACH_O_LC_SYMTAB:
	  if (bfd_mach_o_scan_write_symtab (abfd, cur) != 0)
	    return FALSE;
	  break;
	case BFD_MACH_O_LC_SYMSEG:
	  break;
	case BFD_MACH_O_LC_THREAD:
	case BFD_MACH_O_LC_UNIXTHREAD:
	  if (bfd_mach_o_scan_write_thread (abfd, cur) != 0)
	    return FALSE;
	  break;
	case BFD_MACH_O_LC_LOADFVMLIB:
	case BFD_MACH_O_LC_IDFVMLIB:
	case BFD_MACH_O_LC_IDENT:
	case BFD_MACH_O_LC_FVMFILE:
	case BFD_MACH_O_LC_PREPAGE:
	case BFD_MACH_O_LC_DYSYMTAB:
	case BFD_MACH_O_LC_LOAD_DYLIB:
	case BFD_MACH_O_LC_LOAD_WEAK_DYLIB:
	case BFD_MACH_O_LC_ID_DYLIB:
	case BFD_MACH_O_LC_LOAD_DYLINKER:
	case BFD_MACH_O_LC_ID_DYLINKER:
	case BFD_MACH_O_LC_PREBOUND_DYLIB:
	case BFD_MACH_O_LC_ROUTINES:
	case BFD_MACH_O_LC_SUB_FRAMEWORK:
	  break;
	default:
	  fprintf (stderr,
		   "unable to write unknown load command 0x%lx\n",
		   (long) cur->type);
	  return FALSE;
	}
    }

  return TRUE;
}

static int
bfd_mach_o_sizeof_headers (a, b)
     bfd *a ATTRIBUTE_UNUSED;
     bfd_boolean b ATTRIBUTE_UNUSED;
{
  return 0;
}

/* Make an empty symbol.  This is required only because
   bfd_make_section_anyway wants to create a symbol for the section.  */

static asymbol *
bfd_mach_o_make_empty_symbol (abfd)
     bfd *abfd;
{
  asymbol *new;

  new = (asymbol *) bfd_zalloc (abfd, sizeof (asymbol));
  if (new == NULL)
    return new;
  new->the_bfd = abfd;
  return new;
}

static int
bfd_mach_o_write_header (abfd, header)
     bfd *abfd;
     bfd_mach_o_header *header;
{
  unsigned char buf[28];

  bfd_h_put_32 (abfd, header->magic, buf + 0);
  bfd_h_put_32 (abfd, header->cputype, buf + 4);
  bfd_h_put_32 (abfd, header->cpusubtype, buf + 8);
  bfd_h_put_32 (abfd, header->filetype, buf + 12);
  bfd_h_put_32 (abfd, header->ncmds, buf + 16);
  bfd_h_put_32 (abfd, header->sizeofcmds, buf + 20);
  bfd_h_put_32 (abfd, header->flags, buf + 24);

  bfd_seek (abfd, 0, SEEK_SET);
  if (bfd_bwrite ((PTR) buf, 28, abfd) != 28)
    return -1;

  return 0;
}

static int
bfd_mach_o_read_header (abfd, header)
     bfd *abfd;
     bfd_mach_o_header *header;
{
  unsigned char buf[28];
  bfd_vma (*get32) (const void *) = NULL;

  bfd_seek (abfd, 0, SEEK_SET);

  if (bfd_bread ((PTR) buf, 28, abfd) != 28)
    return -1;

  if (bfd_getb32 (buf) == 0xfeedface)
    {
      header->byteorder = BFD_ENDIAN_BIG;
      header->magic = 0xfeedface;
      get32 = bfd_getb32;
    }
  else if (bfd_getl32 (buf) == 0xfeedface)
    {
      header->byteorder = BFD_ENDIAN_LITTLE;
      header->magic = 0xfeedface;
      get32 = bfd_getl32;
    }
  else
    {
      header->byteorder = BFD_ENDIAN_UNKNOWN;
      return -1;
    }

  header->cputype = (*get32) (buf + 4);
  header->cpusubtype = (*get32) (buf + 8);
  header->filetype = (*get32) (buf + 12);
  header->ncmds = (*get32) (buf + 16);
  header->sizeofcmds = (*get32) (buf + 20);
  header->flags = (*get32) (buf + 24);

  return 0;
}

static asection *
bfd_mach_o_make_bfd_section (abfd, section)
     bfd *abfd;
     bfd_mach_o_section *section;
{
  asection *bfdsec;
  char *sname;
  const char *prefix = "LC_SEGMENT";
  unsigned int snamelen;

  snamelen = strlen (prefix) + 1
    + strlen (section->segname) + 1
    + strlen (section->sectname) + 1;

  sname = (char *) bfd_alloc (abfd, snamelen);
  if (sname == NULL)
    return NULL;
  sprintf (sname, "%s.%s.%s", prefix, section->segname, section->sectname);

  bfdsec = bfd_make_section_anyway (abfd, sname);
  if (bfdsec == NULL)
    return NULL;

  bfdsec->vma = section->addr;
  bfdsec->lma = section->addr;
  bfdsec->size = section->size;
  bfdsec->filepos = section->offset;
  bfdsec->alignment_power = section->align;

  if (section->flags & BFD_MACH_O_S_ZEROFILL)
    bfdsec->flags = SEC_ALLOC;
  else
    bfdsec->flags = SEC_HAS_CONTENTS | SEC_LOAD | SEC_ALLOC | SEC_CODE;

  return bfdsec;
}

static int
bfd_mach_o_scan_read_section (abfd, section, offset)
     bfd *abfd;
     bfd_mach_o_section *section;
     bfd_vma offset;
{
  unsigned char buf[68];

  bfd_seek (abfd, offset, SEEK_SET);
  if (bfd_bread ((PTR) buf, 68, abfd) != 68)
    return -1;

  memcpy (section->sectname, buf, 16);
  section->sectname[16] = '\0';
  memcpy (section->segname, buf + 16, 16);
  section->segname[16] = '\0';
  section->addr = bfd_h_get_32 (abfd, buf + 32);
  section->size = bfd_h_get_32 (abfd, buf + 36);
  section->offset = bfd_h_get_32 (abfd, buf + 40);
  section->align = bfd_h_get_32 (abfd, buf + 44);
  section->reloff = bfd_h_get_32 (abfd, buf + 48);
  section->nreloc = bfd_h_get_32 (abfd, buf + 52);
  section->flags = bfd_h_get_32 (abfd, buf + 56);
  section->reserved1 = bfd_h_get_32 (abfd, buf + 60);
  section->reserved2 = bfd_h_get_32 (abfd, buf + 64);
  section->bfdsection = bfd_mach_o_make_bfd_section (abfd, section);

  if (section->bfdsection == NULL)
    return -1;

  return 0;
}

static int
bfd_mach_o_scan_write_section (abfd, section, offset)
     bfd *abfd;
     bfd_mach_o_section *section;
     bfd_vma offset;
{
  unsigned char buf[68];

  memcpy (buf, section->sectname, 16);
  memcpy (buf + 16, section->segname, 16);
  bfd_h_put_32 (abfd, section->addr, buf + 32);
  bfd_h_put_32 (abfd, section->size, buf + 36);
  bfd_h_put_32 (abfd, section->offset, buf + 40);
  bfd_h_put_32 (abfd, section->align, buf + 44);
  bfd_h_put_32 (abfd, section->reloff, buf + 48);
  bfd_h_put_32 (abfd, section->nreloc, buf + 52);
  bfd_h_put_32 (abfd, section->flags, buf + 56);
  /* bfd_h_put_32 (abfd, section->reserved1, buf + 60); */
  /* bfd_h_put_32 (abfd, section->reserved2, buf + 64); */

  bfd_seek (abfd, offset, SEEK_SET);
  if (bfd_bwrite ((PTR) buf, 68, abfd) != 68)
    return -1;

  return 0;
}

static int
bfd_mach_o_scan_write_symtab_symbols (abfd, command)
     bfd *abfd;
     bfd_mach_o_load_command *command;
{
  bfd_mach_o_symtab_command *sym = &command->command.symtab;
  asymbol *s = NULL;
  unsigned long i;

  for (i = 0; i < sym->nsyms; i++)
    {
      unsigned char buf[12];
      bfd_vma symoff = sym->symoff + (i * 12);
      unsigned char ntype = 0;
      unsigned char nsect = 0;
      short ndesc = 0;

      s = &sym->symbols[i];

      /* Instead just set from the stored values.  */
      ntype = (s->udata.i >> 24) & 0xff;
      nsect = (s->udata.i >> 16) & 0xff;
      ndesc = s->udata.i & 0xffff;

      bfd_h_put_32 (abfd, s->name - sym->strtab, buf);
      bfd_h_put_8 (abfd, ntype, buf + 4);
      bfd_h_put_8 (abfd, nsect, buf + 5);
      bfd_h_put_16 (abfd, ndesc, buf + 6);
      bfd_h_put_32 (abfd, s->section->vma + s->value, buf + 8);

      bfd_seek (abfd, symoff, SEEK_SET);
      if (bfd_bwrite ((PTR) buf, 12, abfd) != 12)
	{
	  fprintf (stderr, "bfd_mach_o_scan_write_symtab_symbols: unable to write %d bytes at %lu\n",
		   12, (unsigned long) symoff);
	  return -1;
	}
    }

  return 0;
}

int
bfd_mach_o_scan_read_symtab_symbol (abfd, sym, s, i)
     bfd *abfd;
     bfd_mach_o_symtab_command *sym;
     asymbol *s;
     unsigned long i;
{
  bfd_mach_o_data_struct *mdata = abfd->tdata.mach_o_data;
  bfd_vma symoff = sym->symoff + (i * 12);
  unsigned char buf[12];
  unsigned char type = -1;
  unsigned char section = -1;
  short desc = -1;
  unsigned long value = -1;
  unsigned long stroff = -1;
  unsigned int symtype = -1;

  BFD_ASSERT (sym->strtab != NULL);

  bfd_seek (abfd, symoff, SEEK_SET);
  if (bfd_bread ((PTR) buf, 12, abfd) != 12)
    {
      fprintf (stderr, "bfd_mach_o_scan_read_symtab_symbol: unable to read %d bytes at %lu\n",
	       12, (unsigned long) symoff);
      return -1;
    }

  stroff = bfd_h_get_32 (abfd, buf);
  type = bfd_h_get_8 (abfd, buf + 4);
  symtype = (type & 0x0e);
  section = bfd_h_get_8 (abfd, buf + 5) - 1;
  desc = bfd_h_get_16 (abfd, buf + 6);
  value = bfd_h_get_32 (abfd, buf + 8);

  if (stroff >= sym->strsize)
    {
      fprintf (stderr, "bfd_mach_o_scan_read_symtab_symbol: symbol name out of range (%lu >= %lu)\n",
	       (unsigned long) stroff, (unsigned long) sym->strsize);
      return -1;
    }

  s->the_bfd = abfd;
  s->name = sym->strtab + stroff;
  s->value = value;
  s->udata.i = (type << 24) | (section << 16) | desc;
  s->flags = 0x0;

  if (type & BFD_MACH_O_N_STAB)
    {
      s->flags |= BSF_DEBUGGING;
      s->section = bfd_und_section_ptr;
    }
  else
    {
      if (type & BFD_MACH_O_N_PEXT)
	{
	  type &= ~BFD_MACH_O_N_PEXT;
	  s->flags |= BSF_GLOBAL;
	}

      if (type & BFD_MACH_O_N_EXT)
	{
	  type &= ~BFD_MACH_O_N_EXT;
	  s->flags |= BSF_GLOBAL;
	}

      switch (symtype)
	{
	case BFD_MACH_O_N_UNDF:
	  s->section = bfd_und_section_ptr;
	  break;
	case BFD_MACH_O_N_PBUD:
	  s->section = bfd_und_section_ptr;
	  break;
	case BFD_MACH_O_N_ABS:
	  s->section = bfd_abs_section_ptr;
	  break;
	case BFD_MACH_O_N_SECT:
	  if ((section > 0) && (section <= mdata->nsects))
	    {
	      s->section = mdata->sections[section - 1]->bfdsection;
	      s->value = s->value - mdata->sections[section - 1]->addr;
	    }
	  else
	    {
	      /* Mach-O uses 0 to mean "no section"; not an error.  */
	      if (section != 0)
		{
		  fprintf (stderr, "bfd_mach_o_scan_read_symtab_symbol: "
			   "symbol \"%s\" specified invalid section %d (max %lu): setting to undefined\n",
			   s->name, section, mdata->nsects);
		}
	      s->section = bfd_und_section_ptr;
	    }
	  break;
	case BFD_MACH_O_N_INDR:
	  fprintf (stderr, "bfd_mach_o_scan_read_symtab_symbol: "
		   "symbol \"%s\" is unsupported 'indirect' reference: setting to undefined\n",
		   s->name);
	  s->section = bfd_und_section_ptr;
	  break;
	default:
	  fprintf (stderr, "bfd_mach_o_scan_read_symtab_symbol: "
		   "symbol \"%s\" specified invalid type field 0x%x: setting to undefined\n",
		   s->name, symtype);
	  s->section = bfd_und_section_ptr;
	  break;
	}
    }

  return 0;
}

int
bfd_mach_o_scan_read_symtab_strtab (abfd, sym)
     bfd *abfd;
     bfd_mach_o_symtab_command *sym;
{
  BFD_ASSERT (sym->strtab == NULL);

  if (abfd->flags & BFD_IN_MEMORY)
    {
      struct bfd_in_memory *b;

      b = (struct bfd_in_memory *) abfd->iostream;

      if ((sym->stroff + sym->strsize) > b->size)
	{
	  bfd_set_error (bfd_error_file_truncated);
	  return -1;
	}
      sym->strtab = (char *) b->buffer + sym->stroff;
      return 0;
    }

  sym->strtab = bfd_alloc (abfd, sym->strsize);
  if (sym->strtab == NULL)
    return -1;

  bfd_seek (abfd, sym->stroff, SEEK_SET);
  if (bfd_bread ((PTR) sym->strtab, sym->strsize, abfd) != sym->strsize)
    {
      fprintf (stderr, "bfd_mach_o_scan_read_symtab_strtab: unable to read %lu bytes at %lu\n",
	       sym->strsize, sym->stroff);
      return -1;
    }

  return 0;
}

int
bfd_mach_o_scan_read_symtab_symbols (abfd, sym)
     bfd *abfd;
     bfd_mach_o_symtab_command *sym;
{
  unsigned long i;
  int ret;

  BFD_ASSERT (sym->symbols == NULL);
  sym->symbols = bfd_alloc (abfd, sym->nsyms * sizeof (asymbol));

  if (sym->symbols == NULL)
    {
      fprintf (stderr, "bfd_mach_o_scan_read_symtab_symbols: unable to allocate memory for symbols\n");
      return -1;
    }

  ret = bfd_mach_o_scan_read_symtab_strtab (abfd, sym);
  if (ret != 0)
    return ret;

  for (i = 0; i < sym->nsyms; i++)
    {
      ret = bfd_mach_o_scan_read_symtab_symbol (abfd, sym, &sym->symbols[i], i);
      if (ret != 0)
	return ret;
    }

  return 0;
}

int
bfd_mach_o_scan_read_dysymtab_symbol (abfd, dysym, sym, s, i)
     bfd *abfd;
     bfd_mach_o_dysymtab_command *dysym;
     bfd_mach_o_symtab_command *sym;
     asymbol *s;
     unsigned long i;
{
  unsigned long isymoff = dysym->indirectsymoff + (i * 4);
  unsigned long symindex;
  unsigned char buf[4];

  BFD_ASSERT (i < dysym->nindirectsyms);

  bfd_seek (abfd, isymoff, SEEK_SET);
  if (bfd_bread ((PTR) buf, 4, abfd) != 4)
    {
      fprintf (stderr, "bfd_mach_o_scan_read_dysymtab_symbol: unable to read %lu bytes at %lu\n",
	       (unsigned long) 4, isymoff);
      return -1;
    }
  symindex = bfd_h_get_32 (abfd, buf);

  return bfd_mach_o_scan_read_symtab_symbol (abfd, sym, s, symindex);
}

static const char *
bfd_mach_o_i386_flavour_string (flavour)
     unsigned int flavour;
{
  switch ((int) flavour)
    {
    case BFD_MACH_O_i386_NEW_THREAD_STATE: return "i386_NEW_THREAD_STATE";
    case BFD_MACH_O_i386_FLOAT_STATE: return "i386_FLOAT_STATE";
    case BFD_MACH_O_i386_ISA_PORT_MAP_STATE: return "i386_ISA_PORT_MAP_STATE";
    case BFD_MACH_O_i386_V86_ASSIST_STATE: return "i386_V86_ASSIST_STATE";
    case BFD_MACH_O_i386_REGS_SEGS_STATE: return "i386_REGS_SEGS_STATE";
    case BFD_MACH_O_i386_THREAD_SYSCALL_STATE: return "i386_THREAD_SYSCALL_STATE";
    case BFD_MACH_O_i386_THREAD_STATE_NONE: return "i386_THREAD_STATE_NONE";
    case BFD_MACH_O_i386_SAVED_STATE: return "i386_SAVED_STATE";
    case BFD_MACH_O_i386_THREAD_STATE: return "i386_THREAD_STATE";
    case BFD_MACH_O_i386_THREAD_FPSTATE: return "i386_THREAD_FPSTATE";
    case BFD_MACH_O_i386_THREAD_EXCEPTSTATE: return "i386_THREAD_EXCEPTSTATE";
    case BFD_MACH_O_i386_THREAD_CTHREADSTATE: return "i386_THREAD_CTHREADSTATE";
    default: return "UNKNOWN";
    }
}

static const char *
bfd_mach_o_ppc_flavour_string (flavour)
     unsigned int flavour;
{
  switch ((int) flavour)
    {
    case BFD_MACH_O_PPC_THREAD_STATE: return "PPC_THREAD_STATE";
    case BFD_MACH_O_PPC_FLOAT_STATE: return "PPC_FLOAT_STATE";
    case BFD_MACH_O_PPC_EXCEPTION_STATE: return "PPC_EXCEPTION_STATE";
    case BFD_MACH_O_PPC_VECTOR_STATE: return "PPC_VECTOR_STATE";
    default: return "UNKNOWN";
    }
}

static int
bfd_mach_o_scan_write_thread (abfd, command)
     bfd *abfd;
     bfd_mach_o_load_command *command;
{
  bfd_mach_o_thread_command *cmd = &command->command.thread;
  unsigned int i;
  unsigned char buf[8];
  bfd_vma offset;
  unsigned int nflavours;

  BFD_ASSERT ((command->type == BFD_MACH_O_LC_THREAD)
	      || (command->type == BFD_MACH_O_LC_UNIXTHREAD));

  offset = 8;
  nflavours = 0;
  for (i = 0; i < cmd->nflavours; i++)
    {
      BFD_ASSERT ((cmd->flavours[i].size % 4) == 0);
      BFD_ASSERT (cmd->flavours[i].offset == (command->offset + offset + 8));

      bfd_h_put_32 (abfd, cmd->flavours[i].flavour, buf);
      bfd_h_put_32 (abfd, (cmd->flavours[i].size / 4), buf + 4);

      bfd_seek (abfd, command->offset + offset, SEEK_SET);
      if (bfd_bwrite ((PTR) buf, 8, abfd) != 8)
	return -1;

      offset += cmd->flavours[i].size + 8;
    }

  return 0;
}

static int
bfd_mach_o_scan_read_dylinker (abfd, command)
     bfd *abfd;
     bfd_mach_o_load_command *command;
{
  bfd_mach_o_dylinker_command *cmd = &command->command.dylinker;
  unsigned char buf[4];
  unsigned int nameoff;
  asection *bfdsec;
  char *sname;
  const char *prefix;

  BFD_ASSERT ((command->type == BFD_MACH_O_LC_ID_DYLINKER)
	      || (command->type == BFD_MACH_O_LC_LOAD_DYLINKER));

  bfd_seek (abfd, command->offset + 8, SEEK_SET);
  if (bfd_bread ((PTR) buf, 4, abfd) != 4)
    return -1;

  nameoff = bfd_h_get_32 (abfd, buf + 0);

  cmd->name_offset = command->offset + nameoff;
  cmd->name_len = command->len - nameoff;

  if (command->type == BFD_MACH_O_LC_LOAD_DYLINKER)
    prefix = "LC_LOAD_DYLINKER";
  else if (command->type == BFD_MACH_O_LC_ID_DYLINKER)
    prefix = "LC_ID_DYLINKER";
  else
    abort ();

  sname = (char *) bfd_alloc (abfd, strlen (prefix) + 1);
  if (sname == NULL)
    return -1;
  strcpy (sname, prefix);

  bfdsec = bfd_make_section_anyway (abfd, sname);
  if (bfdsec == NULL)
    return -1;

  bfdsec->vma = 0;
  bfdsec->lma = 0;
  bfdsec->size = command->len - 8;
  bfdsec->filepos = command->offset + 8;
  bfdsec->alignment_power = 0;
  bfdsec->flags = SEC_HAS_CONTENTS;

  cmd->section = bfdsec;

  return 0;
}

static int
bfd_mach_o_scan_read_dylib (abfd, command)
     bfd *abfd;
     bfd_mach_o_load_command *command;
{
  bfd_mach_o_dylib_command *cmd = &command->command.dylib;
  unsigned char buf[16];
  unsigned int nameoff;
  asection *bfdsec;
  char *sname;
  const char *prefix;

  BFD_ASSERT ((command->type == BFD_MACH_O_LC_ID_DYLIB)
	      || (command->type == BFD_MACH_O_LC_LOAD_DYLIB)
	      || (command->type == BFD_MACH_O_LC_LOAD_WEAK_DYLIB));

  bfd_seek (abfd, command->offset + 8, SEEK_SET);
  if (bfd_bread ((PTR) buf, 16, abfd) != 16)
    return -1;

  nameoff = bfd_h_get_32 (abfd, buf + 0);
  cmd->timestamp = bfd_h_get_32 (abfd, buf + 4);
  cmd->current_version = bfd_h_get_32 (abfd, buf + 8);
  cmd->compatibility_version = bfd_h_get_32 (abfd, buf + 12);

  cmd->name_offset = command->offset + nameoff;
  cmd->name_len = command->len - nameoff;

  if (command->type == BFD_MACH_O_LC_LOAD_DYLIB)
    prefix = "LC_LOAD_DYLIB";
  else if (command->type == BFD_MACH_O_LC_LOAD_WEAK_DYLIB)
    prefix = "LC_LOAD_WEAK_DYLIB";
  else if (command->type == BFD_MACH_O_LC_ID_DYLIB)
    prefix = "LC_ID_DYLIB";
  else
    abort ();

  sname = (char *) bfd_alloc (abfd, strlen (prefix) + 1);
  if (sname == NULL)
    return -1;
  strcpy (sname, prefix);

  bfdsec = bfd_make_section_anyway (abfd, sname);
  if (bfdsec == NULL)
    return -1;

  bfdsec->vma = 0;
  bfdsec->lma = 0;
  bfdsec->size = command->len - 8;
  bfdsec->filepos = command->offset + 8;
  bfdsec->alignment_power = 0;
  bfdsec->flags = SEC_HAS_CONTENTS;

  cmd->section = bfdsec;

  return 0;
}

static int
bfd_mach_o_scan_read_prebound_dylib (abfd, command)
     bfd *abfd ATTRIBUTE_UNUSED;
     bfd_mach_o_load_command *command ATTRIBUTE_UNUSED;
{
  /* bfd_mach_o_prebound_dylib_command *cmd = &command->command.prebound_dylib; */

  BFD_ASSERT (command->type == BFD_MACH_O_LC_PREBOUND_DYLIB);
  return 0;
}

static int
bfd_mach_o_scan_read_thread (abfd, command)
     bfd *abfd;
     bfd_mach_o_load_command *command;
{
  bfd_mach_o_data_struct *mdata = NULL;
  bfd_mach_o_thread_command *cmd = &command->command.thread;
  unsigned char buf[8];
  bfd_vma offset;
  unsigned int nflavours;
  unsigned int i;

  BFD_ASSERT ((command->type == BFD_MACH_O_LC_THREAD)
	      || (command->type == BFD_MACH_O_LC_UNIXTHREAD));

  BFD_ASSERT (bfd_mach_o_valid (abfd));
  mdata = abfd->tdata.mach_o_data;

  offset = 8;
  nflavours = 0;
  while (offset != command->len)
    {
      if (offset >= command->len)
	return -1;

      bfd_seek (abfd, command->offset + offset, SEEK_SET);

      if (bfd_bread ((PTR) buf, 8, abfd) != 8)
	return -1;

      offset += 8 + bfd_h_get_32 (abfd, buf + 4) * 4;
      nflavours++;
    }

  cmd->flavours =
    ((bfd_mach_o_thread_flavour *)
     bfd_alloc (abfd, nflavours * sizeof (bfd_mach_o_thread_flavour)));
  if (cmd->flavours == NULL)
    return -1;
  cmd->nflavours = nflavours;

  offset = 8;
  nflavours = 0;
  while (offset != command->len)
    {
      if (offset >= command->len)
	return -1;

      if (nflavours >= cmd->nflavours)
	return -1;

      bfd_seek (abfd, command->offset + offset, SEEK_SET);

      if (bfd_bread ((PTR) buf, 8, abfd) != 8)
	return -1;

      cmd->flavours[nflavours].flavour = bfd_h_get_32 (abfd, buf);
      cmd->flavours[nflavours].offset = command->offset + offset + 8;
      cmd->flavours[nflavours].size = bfd_h_get_32 (abfd, buf + 4) * 4;
      offset += cmd->flavours[nflavours].size + 8;
      nflavours++;
    }

  for (i = 0; i < nflavours; i++)
    {
      asection *bfdsec;
      unsigned int snamelen;
      char *sname;
      const char *flavourstr;
      const char *prefix = "LC_THREAD";
      unsigned int j = 0;

      switch (mdata->header.cputype)
	{
	case BFD_MACH_O_CPU_TYPE_POWERPC:
	  flavourstr = bfd_mach_o_ppc_flavour_string (cmd->flavours[i].flavour);
	  break;
	case BFD_MACH_O_CPU_TYPE_I386:
	  flavourstr = bfd_mach_o_i386_flavour_string (cmd->flavours[i].flavour);
	  break;
	default:
	  flavourstr = "UNKNOWN_ARCHITECTURE";
	  break;
	}

      snamelen = strlen (prefix) + 1 + 20 + 1 + strlen (flavourstr) + 1;
      sname = (char *) bfd_alloc (abfd, snamelen);
      if (sname == NULL)
	return -1;

      for (;;)
	{
	  sprintf (sname, "%s.%s.%u", prefix, flavourstr, j);
	  if (bfd_get_section_by_name (abfd, sname) == NULL)
	    break;
	  j++;
	}

      bfdsec = bfd_make_section (abfd, sname);

      bfdsec->vma = 0;
      bfdsec->lma = 0;
      bfdsec->size = cmd->flavours[i].size;
      bfdsec->filepos = cmd->flavours[i].offset;
      bfdsec->alignment_power = 0x0;
      bfdsec->flags = SEC_HAS_CONTENTS;

      cmd->section = bfdsec;
    }

  return 0;
}

static int
bfd_mach_o_scan_write_symtab (abfd, command)
     bfd *abfd;
     bfd_mach_o_load_command *command;
{
  bfd_mach_o_symtab_command *seg = &command->command.symtab;
  unsigned char buf[16];

  BFD_ASSERT (command->type == BFD_MACH_O_LC_SYMTAB);

  bfd_h_put_32 (abfd, seg->symoff, buf);
  bfd_h_put_32 (abfd, seg->nsyms, buf + 4);
  bfd_h_put_32 (abfd, seg->stroff, buf + 8);
  bfd_h_put_32 (abfd, seg->strsize, buf + 12);

  bfd_seek (abfd, command->offset + 8, SEEK_SET);
  if (bfd_bwrite ((PTR) buf, 16, abfd) != 16)
    return -1;

  if (bfd_mach_o_scan_write_symtab_symbols (abfd, command) != 0)
    return -1;

  return 0;
}

static int
bfd_mach_o_scan_read_dysymtab (abfd, command)
     bfd *abfd;
     bfd_mach_o_load_command *command;
{
  bfd_mach_o_dysymtab_command *seg = &command->command.dysymtab;
  unsigned char buf[72];

  BFD_ASSERT (command->type == BFD_MACH_O_LC_DYSYMTAB);

  bfd_seek (abfd, command->offset + 8, SEEK_SET);
  if (bfd_bread ((PTR) buf, 72, abfd) != 72)
    return -1;

  seg->ilocalsym = bfd_h_get_32 (abfd, buf + 0);
  seg->nlocalsym = bfd_h_get_32 (abfd, buf + 4);
  seg->iextdefsym = bfd_h_get_32 (abfd, buf + 8);
  seg->nextdefsym = bfd_h_get_32 (abfd, buf + 12);
  seg->iundefsym = bfd_h_get_32 (abfd, buf + 16);
  seg->nundefsym = bfd_h_get_32 (abfd, buf + 20);
  seg->tocoff = bfd_h_get_32 (abfd, buf + 24);
  seg->ntoc = bfd_h_get_32 (abfd, buf + 28);
  seg->modtaboff = bfd_h_get_32 (abfd, buf + 32);
  seg->nmodtab = bfd_h_get_32 (abfd, buf + 36);
  seg->extrefsymoff = bfd_h_get_32 (abfd, buf + 40);
  seg->nextrefsyms = bfd_h_get_32 (abfd, buf + 44);
  seg->indirectsymoff = bfd_h_get_32 (abfd, buf + 48);
  seg->nindirectsyms = bfd_h_get_32 (abfd, buf + 52);
  seg->extreloff = bfd_h_get_32 (abfd, buf + 56);
  seg->nextrel = bfd_h_get_32 (abfd, buf + 60);
  seg->locreloff = bfd_h_get_32 (abfd, buf + 64);
  seg->nlocrel = bfd_h_get_32 (abfd, buf + 68);

  return 0;
}

static int
bfd_mach_o_scan_read_symtab (abfd, command)
     bfd *abfd;
     bfd_mach_o_load_command *command;
{
  bfd_mach_o_symtab_command *seg = &command->command.symtab;
  unsigned char buf[16];
  asection *bfdsec;
  char *sname;
  const char *prefix = "LC_SYMTAB.stabs";

  BFD_ASSERT (command->type == BFD_MACH_O_LC_SYMTAB);

  bfd_seek (abfd, command->offset + 8, SEEK_SET);
  if (bfd_bread ((PTR) buf, 16, abfd) != 16)
    return -1;

  seg->symoff = bfd_h_get_32 (abfd, buf);
  seg->nsyms = bfd_h_get_32 (abfd, buf + 4);
  seg->stroff = bfd_h_get_32 (abfd, buf + 8);
  seg->strsize = bfd_h_get_32 (abfd, buf + 12);
  seg->symbols = NULL;
  seg->strtab = NULL;

  sname = (char *) bfd_alloc (abfd, strlen (prefix) + 1);
  if (sname == NULL)
    return -1;
  strcpy (sname, prefix);

  bfdsec = bfd_make_section_anyway (abfd, sname);
  if (bfdsec == NULL)
    return -1;

  bfdsec->vma = 0;
  bfdsec->lma = 0;
  bfdsec->size = seg->nsyms * 12;
  bfdsec->filepos = seg->symoff;
  bfdsec->alignment_power = 0;
  bfdsec->flags = SEC_HAS_CONTENTS;

  seg->stabs_segment = bfdsec;

  prefix = "LC_SYMTAB.stabstr";
  sname = (char *) bfd_alloc (abfd, strlen (prefix) + 1);
  if (sname == NULL)
    return -1;
  strcpy (sname, prefix);

  bfdsec = bfd_make_section_anyway (abfd, sname);
  if (bfdsec == NULL)
    return -1;

  bfdsec->vma = 0;
  bfdsec->lma = 0;
  bfdsec->size = seg->strsize;
  bfdsec->filepos = seg->stroff;
  bfdsec->alignment_power = 0;
  bfdsec->flags = SEC_HAS_CONTENTS;

  seg->stabstr_segment = bfdsec;

  return 0;
}

static int
bfd_mach_o_scan_read_segment (abfd, command)
     bfd *abfd;
     bfd_mach_o_load_command *command;
{
  unsigned char buf[48];
  bfd_mach_o_segment_command *seg = &command->command.segment;
  unsigned long i;
  asection *bfdsec;
  char *sname;
  const char *prefix = "LC_SEGMENT";
  unsigned int snamelen;

  BFD_ASSERT (command->type == BFD_MACH_O_LC_SEGMENT);

  bfd_seek (abfd, command->offset + 8, SEEK_SET);
  if (bfd_bread ((PTR) buf, 48, abfd) != 48)
    return -1;

  memcpy (seg->segname, buf, 16);
  seg->vmaddr = bfd_h_get_32 (abfd, buf + 16);
  seg->vmsize = bfd_h_get_32 (abfd, buf + 20);
  seg->fileoff = bfd_h_get_32 (abfd, buf + 24);
  seg->filesize = bfd_h_get_32 (abfd, buf +  28);
  /* seg->maxprot = bfd_h_get_32 (abfd, buf + 32); */
  /* seg->initprot = bfd_h_get_32 (abfd, buf + 36); */
  seg->nsects = bfd_h_get_32 (abfd, buf + 40);
  seg->flags = bfd_h_get_32 (abfd, buf + 44);

  snamelen = strlen (prefix) + 1 + strlen (seg->segname) + 1;
  sname = (char *) bfd_alloc (abfd, snamelen);
  if (sname == NULL)
    return -1;
  sprintf (sname, "%s.%s", prefix, seg->segname);

  bfdsec = bfd_make_section_anyway (abfd, sname);
  if (bfdsec == NULL)
    return -1;

  bfdsec->vma = seg->vmaddr;
  bfdsec->lma = seg->vmaddr;
  bfdsec->size = seg->filesize;
  bfdsec->filepos = seg->fileoff;
  bfdsec->alignment_power = 0x0;
  bfdsec->flags = SEC_HAS_CONTENTS | SEC_LOAD | SEC_ALLOC | SEC_CODE;

  seg->segment = bfdsec;

  if (seg->nsects != 0)
    {
      seg->sections =
	((bfd_mach_o_section *)
	 bfd_alloc (abfd, seg->nsects * sizeof (bfd_mach_o_section)));
      if (seg->sections == NULL)
	return -1;

      for (i = 0; i < seg->nsects; i++)
	{
	  bfd_vma segoff = command->offset + 48 + 8 + (i * 68);

	  if (bfd_mach_o_scan_read_section (abfd, &seg->sections[i],
					    segoff) != 0)
	    return -1;
	}
    }

  return 0;
}

static int
bfd_mach_o_scan_write_segment (abfd, command)
     bfd *abfd;
     bfd_mach_o_load_command *command;
{
  unsigned char buf[48];
  bfd_mach_o_segment_command *seg = &command->command.segment;
  unsigned long i;

  BFD_ASSERT (command->type == BFD_MACH_O_LC_SEGMENT);

  memcpy (buf, seg->segname, 16);
  bfd_h_put_32 (abfd, seg->vmaddr, buf + 16);
  bfd_h_put_32 (abfd, seg->vmsize, buf + 20);
  bfd_h_put_32 (abfd, seg->fileoff, buf + 24);
  bfd_h_put_32 (abfd, seg->filesize, buf + 28);
  bfd_h_put_32 (abfd, 0 /* seg->maxprot */, buf + 32);
  bfd_h_put_32 (abfd, 0 /* seg->initprot */, buf + 36);
  bfd_h_put_32 (abfd, seg->nsects, buf + 40);
  bfd_h_put_32 (abfd, seg->flags, buf + 44);

  bfd_seek (abfd, command->offset + 8, SEEK_SET);
  if (bfd_bwrite ((PTR) buf, 48, abfd) != 48)
    return -1;

  {
    char buf[1024];
    bfd_vma nbytes = seg->filesize;
    bfd_vma curoff = seg->fileoff;

    while (nbytes > 0)
      {
	bfd_vma thisread = nbytes;

	if (thisread > 1024)
	  thisread = 1024;

	bfd_seek (abfd, curoff, SEEK_SET);
	if (bfd_bread ((PTR) buf, thisread, abfd) != thisread)
	  return -1;

	bfd_seek (abfd, curoff, SEEK_SET);
	if (bfd_bwrite ((PTR) buf, thisread, abfd) != thisread)
	  return -1;

	nbytes -= thisread;
	curoff += thisread;
      }
  }

  for (i = 0; i < seg->nsects; i++)
    {
      bfd_vma segoff = command->offset + 48 + 8 + (i * 68);

      if (bfd_mach_o_scan_write_section (abfd, &seg->sections[i], segoff) != 0)
	return -1;
    }

  return 0;
}

static int
bfd_mach_o_scan_read_command (abfd, command)
     bfd *abfd;
     bfd_mach_o_load_command *command;
{
  unsigned char buf[8];

  bfd_seek (abfd, command->offset, SEEK_SET);
  if (bfd_bread ((PTR) buf, 8, abfd) != 8)
    return -1;

  command->type = (bfd_h_get_32 (abfd, buf) & ~BFD_MACH_O_LC_REQ_DYLD);
  command->type_required = (bfd_h_get_32 (abfd, buf) & BFD_MACH_O_LC_REQ_DYLD
			    ? 1 : 0);
  command->len = bfd_h_get_32 (abfd, buf + 4);

  switch (command->type)
    {
    case BFD_MACH_O_LC_SEGMENT:
      if (bfd_mach_o_scan_read_segment (abfd, command) != 0)
	return -1;
      break;
    case BFD_MACH_O_LC_SYMTAB:
      if (bfd_mach_o_scan_read_symtab (abfd, command) != 0)
	return -1;
      break;
    case BFD_MACH_O_LC_SYMSEG:
      break;
    case BFD_MACH_O_LC_THREAD:
    case BFD_MACH_O_LC_UNIXTHREAD:
      if (bfd_mach_o_scan_read_thread (abfd, command) != 0)
	return -1;
      break;
    case BFD_MACH_O_LC_LOAD_DYLINKER:
    case BFD_MACH_O_LC_ID_DYLINKER:
      if (bfd_mach_o_scan_read_dylinker (abfd, command) != 0)
	return -1;
      break;
    case BFD_MACH_O_LC_LOAD_DYLIB:
    case BFD_MACH_O_LC_ID_DYLIB:
    case BFD_MACH_O_LC_LOAD_WEAK_DYLIB:
      if (bfd_mach_o_scan_read_dylib (abfd, command) != 0)
	return -1;
      break;
    case BFD_MACH_O_LC_PREBOUND_DYLIB:
      if (bfd_mach_o_scan_read_prebound_dylib (abfd, command) != 0)
	return -1;
      break;
    case BFD_MACH_O_LC_LOADFVMLIB:
    case BFD_MACH_O_LC_IDFVMLIB:
    case BFD_MACH_O_LC_IDENT:
    case BFD_MACH_O_LC_FVMFILE:
    case BFD_MACH_O_LC_PREPAGE:
    case BFD_MACH_O_LC_ROUTINES:
    case BFD_MACH_O_LC_SUB_FRAMEWORK:
      break;
    case BFD_MACH_O_LC_DYSYMTAB:
      if (bfd_mach_o_scan_read_dysymtab (abfd, command) != 0)
	return -1;
      break;
    case BFD_MACH_O_LC_SUB_UMBRELLA:
    case BFD_MACH_O_LC_SUB_CLIENT:
    case BFD_MACH_O_LC_SUB_LIBRARY:
    case BFD_MACH_O_LC_TWOLEVEL_HINTS:
    case BFD_MACH_O_LC_PREBIND_CKSUM:
      break;
    default:
      fprintf (stderr, "unable to read unknown load command 0x%lx\n",
	       (unsigned long) command->type);
      break;
    }

  return 0;
}

static void
bfd_mach_o_flatten_sections (abfd)
     bfd *abfd;
{
  bfd_mach_o_data_struct *mdata = abfd->tdata.mach_o_data;
  long csect = 0;
  unsigned long i, j;

  mdata->nsects = 0;

  for (i = 0; i < mdata->header.ncmds; i++)
    {
      if (mdata->commands[i].type == BFD_MACH_O_LC_SEGMENT)
	{
	  bfd_mach_o_segment_command *seg;

	  seg = &mdata->commands[i].command.segment;
	  mdata->nsects += seg->nsects;
	}
    }

  mdata->sections = bfd_alloc (abfd,
			       mdata->nsects * sizeof (bfd_mach_o_section *));
  csect = 0;

  for (i = 0; i < mdata->header.ncmds; i++)
    {
      if (mdata->commands[i].type == BFD_MACH_O_LC_SEGMENT)
	{
	  bfd_mach_o_segment_command *seg;

	  seg = &mdata->commands[i].command.segment;
	  BFD_ASSERT (csect + seg->nsects <= mdata->nsects);

	  for (j = 0; j < seg->nsects; j++)
	    mdata->sections[csect++] = &seg->sections[j];
	}
    }
}

int
bfd_mach_o_scan_start_address (abfd)
     bfd *abfd;
{
  bfd_mach_o_data_struct *mdata = abfd->tdata.mach_o_data;
  bfd_mach_o_thread_command *cmd = NULL;
  unsigned long i;

  for (i = 0; i < mdata->header.ncmds; i++)
    {
      if ((mdata->commands[i].type == BFD_MACH_O_LC_THREAD) ||
	  (mdata->commands[i].type == BFD_MACH_O_LC_UNIXTHREAD))
	{
	  if (cmd == NULL)
	    cmd = &mdata->commands[i].command.thread;
	  else
	    return 0;
	}
    }

  if (cmd == NULL)
    return 0;

  for (i = 0; i < cmd->nflavours; i++)
    {
      if ((mdata->header.cputype == BFD_MACH_O_CPU_TYPE_I386)
	  && (cmd->flavours[i].flavour
	      == (unsigned long) BFD_MACH_O_i386_THREAD_STATE))
	{
	  unsigned char buf[4];

	  bfd_seek (abfd, cmd->flavours[i].offset + 40, SEEK_SET);

	  if (bfd_bread (buf, 4, abfd) != 4)
	    return -1;

	  abfd->start_address = bfd_h_get_32 (abfd, buf);
	}
      else if ((mdata->header.cputype == BFD_MACH_O_CPU_TYPE_POWERPC)
	       && (cmd->flavours[i].flavour == BFD_MACH_O_PPC_THREAD_STATE))
	{
	  unsigned char buf[4];

	  bfd_seek (abfd, cmd->flavours[i].offset + 0, SEEK_SET);

	  if (bfd_bread (buf, 4, abfd) != 4)
	    return -1;

	  abfd->start_address = bfd_h_get_32 (abfd, buf);
	}
    }

  return 0;
}

int
bfd_mach_o_scan (abfd, header, mdata)
     bfd *abfd;
     bfd_mach_o_header *header;
     bfd_mach_o_data_struct *mdata;
{
  unsigned int i;
  enum bfd_architecture cputype;
  unsigned long cpusubtype;

  mdata->header = *header;
  mdata->symbols = NULL;

  abfd->flags = (abfd->xvec->object_flags
		 | (abfd->flags & (BFD_IN_MEMORY | BFD_IO_FUNCS)));
  abfd->tdata.mach_o_data = mdata;

  bfd_mach_o_convert_architecture (header->cputype, header->cpusubtype,
				   &cputype, &cpusubtype);
  if (cputype == bfd_arch_unknown)
    {
      fprintf (stderr, "bfd_mach_o_scan: unknown architecture 0x%lx/0x%lx\n",
	       header->cputype, header->cpusubtype);
      return -1;
    }

  bfd_set_arch_mach (abfd, cputype, cpusubtype);

  if (header->ncmds != 0)
    {
      mdata->commands =
	((bfd_mach_o_load_command *)
	 bfd_alloc (abfd, header->ncmds * sizeof (bfd_mach_o_load_command)));
      if (mdata->commands == NULL)
	return -1;

      for (i = 0; i < header->ncmds; i++)
	{
	  bfd_mach_o_load_command *cur = &mdata->commands[i];

	  if (i == 0)
	    cur->offset = 28;
	  else
	    {
	      bfd_mach_o_load_command *prev = &mdata->commands[i - 1];
	      cur->offset = prev->offset + prev->len;
	    }

	  if (bfd_mach_o_scan_read_command (abfd, cur) < 0)
	    return -1;
	}
    }

  if (bfd_mach_o_scan_start_address (abfd) < 0)
    return -1;

  bfd_mach_o_flatten_sections (abfd);
  return 0;
}

bfd_boolean
bfd_mach_o_mkobject (abfd)
     bfd *abfd;
{
  bfd_mach_o_data_struct *mdata = NULL;

  mdata = ((bfd_mach_o_data_struct *)
	   bfd_alloc (abfd, sizeof (bfd_mach_o_data_struct)));
  if (mdata == NULL)
    return FALSE;
  abfd->tdata.mach_o_data = mdata;

  mdata->header.magic = 0;
  mdata->header.cputype = 0;
  mdata->header.cpusubtype = 0;
  mdata->header.filetype = 0;
  mdata->header.ncmds = 0;
  mdata->header.sizeofcmds = 0;
  mdata->header.flags = 0;
  mdata->header.byteorder = BFD_ENDIAN_UNKNOWN;
  mdata->commands = NULL;
  mdata->nsymbols = 0;
  mdata->symbols = NULL;
  mdata->nsects = 0;
  mdata->sections = NULL;
  mdata->ibfd = NULL;

  return TRUE;
}

const bfd_target *
bfd_mach_o_object_p (abfd)
     bfd *abfd;
{
  struct bfd_preserve preserve;
  bfd_mach_o_header header;

  preserve.marker = NULL;
  if (bfd_mach_o_read_header (abfd, &header) != 0)
    goto wrong;

  if (! (header.byteorder == BFD_ENDIAN_BIG
	 || header.byteorder == BFD_ENDIAN_LITTLE))
    {
      fprintf (stderr, "unknown header byte-order value 0x%lx\n",
	       (long) header.byteorder);
      goto wrong;
    }

  if (! ((header.byteorder == BFD_ENDIAN_BIG
	  && abfd->xvec->byteorder == BFD_ENDIAN_BIG
	  && abfd->xvec->header_byteorder == BFD_ENDIAN_BIG)
	 || (header.byteorder == BFD_ENDIAN_LITTLE
	     && abfd->xvec->byteorder == BFD_ENDIAN_LITTLE
	     && abfd->xvec->header_byteorder == BFD_ENDIAN_LITTLE)))
    goto wrong;

  preserve.marker = bfd_zalloc (abfd, sizeof (bfd_mach_o_data_struct));
  if (preserve.marker == NULL
      || !bfd_preserve_save (abfd, &preserve))
    goto fail;

  if (bfd_mach_o_scan (abfd, &header,
		       (bfd_mach_o_data_struct *) preserve.marker) != 0)
    goto wrong;

  bfd_preserve_finish (abfd, &preserve);
  return abfd->xvec;

 wrong:
  bfd_set_error (bfd_error_wrong_format);

 fail:
  if (preserve.marker != NULL)
    bfd_preserve_restore (abfd, &preserve);
  return NULL;
}

const bfd_target *
bfd_mach_o_core_p (abfd)
     bfd *abfd;
{
  struct bfd_preserve preserve;
  bfd_mach_o_header header;

  preserve.marker = NULL;
  if (bfd_mach_o_read_header (abfd, &header) != 0)
    goto wrong;

  if (! (header.byteorder == BFD_ENDIAN_BIG
	 || header.byteorder == BFD_ENDIAN_LITTLE))
    {
      fprintf (stderr, "unknown header byte-order value 0x%lx\n",
	       (long) header.byteorder);
      abort ();
    }

  if (! ((header.byteorder == BFD_ENDIAN_BIG
	  && abfd->xvec->byteorder == BFD_ENDIAN_BIG
	  && abfd->xvec->header_byteorder == BFD_ENDIAN_BIG)
	 || (header.byteorder == BFD_ENDIAN_LITTLE
	     && abfd->xvec->byteorder == BFD_ENDIAN_LITTLE
	     && abfd->xvec->header_byteorder == BFD_ENDIAN_LITTLE)))
    goto wrong;

  if (header.filetype != BFD_MACH_O_MH_CORE)
    goto wrong;

  preserve.marker = bfd_zalloc (abfd, sizeof (bfd_mach_o_data_struct));
  if (preserve.marker == NULL
      || !bfd_preserve_save (abfd, &preserve))
    goto fail;

  if (bfd_mach_o_scan (abfd, &header,
		       (bfd_mach_o_data_struct *) preserve.marker) != 0)
    goto wrong;

  bfd_preserve_finish (abfd, &preserve);
  return abfd->xvec;

 wrong:
  bfd_set_error (bfd_error_wrong_format);

 fail:
  if (preserve.marker != NULL)
    bfd_preserve_restore (abfd, &preserve);
  return NULL;
}

typedef struct mach_o_fat_archentry
{
  unsigned long cputype;
  unsigned long cpusubtype;
  unsigned long offset;
  unsigned long size;
  unsigned long align;
  bfd *abfd;
} mach_o_fat_archentry;

typedef struct mach_o_fat_data_struct
{
  unsigned long magic;
  unsigned long nfat_arch;
  mach_o_fat_archentry *archentries;
} mach_o_fat_data_struct;

const bfd_target *
bfd_mach_o_archive_p (abfd)
     bfd *abfd;
{
  mach_o_fat_data_struct *adata = NULL;
  unsigned char buf[20];
  unsigned long i;

  bfd_seek (abfd, 0, SEEK_SET);
  if (bfd_bread ((PTR) buf, 8, abfd) != 8)
    goto error;

  adata = (mach_o_fat_data_struct *)
    bfd_alloc (abfd, sizeof (mach_o_fat_data_struct));
  if (adata == NULL)
    goto error;

  adata->magic = bfd_getb32 (buf);
  adata->nfat_arch = bfd_getb32 (buf + 4);
  if (adata->magic != 0xcafebabe)
    goto error;

  adata->archentries = (mach_o_fat_archentry *)
    bfd_alloc (abfd, adata->nfat_arch * sizeof (mach_o_fat_archentry));
  if (adata->archentries == NULL)
    goto error;

  for (i = 0; i < adata->nfat_arch; i++)
    {
      bfd_seek (abfd, 8 + 20 * i, SEEK_SET);

      if (bfd_bread ((PTR) buf, 20, abfd) != 20)
	goto error;
      adata->archentries[i].cputype = bfd_getb32 (buf);
      adata->archentries[i].cpusubtype = bfd_getb32 (buf + 4);
      adata->archentries[i].offset = bfd_getb32 (buf + 8);
      adata->archentries[i].size = bfd_getb32 (buf + 12);
      adata->archentries[i].align = bfd_getb32 (buf + 16);
      adata->archentries[i].abfd = NULL;
    }

  abfd->tdata.mach_o_fat_data = adata;
  return abfd->xvec;

 error:
  if (adata != NULL)
    bfd_release (abfd, adata);
  bfd_set_error (bfd_error_wrong_format);
  return NULL;
}

bfd *
bfd_mach_o_openr_next_archived_file (archive, prev)
  bfd *archive;
  bfd *prev;
{
  mach_o_fat_data_struct *adata;
  mach_o_fat_archentry *entry = NULL;
  unsigned long i;

  adata = (mach_o_fat_data_struct *) archive->tdata.mach_o_fat_data;
  BFD_ASSERT (adata != NULL);

  /* Find index of previous entry.  */
  if (prev == NULL)
    i = 0;	/* Start at first one.  */
  else
    {
      for (i = 0; i < adata->nfat_arch; i++)
	{
	  if (adata->archentries[i].abfd == prev)
	    break;
	}

      if (i == adata->nfat_arch)
	{
	  /* Not found.  */
	  bfd_set_error (bfd_error_bad_value);
	  return NULL;
	}
    i++;	/* Get next entry.  */
  }

  if (i >= adata->nfat_arch)
    {
      bfd_set_error (bfd_error_no_more_archived_files);
      return NULL;
    }

  entry = &adata->archentries[i];
  if (entry->abfd == NULL)
    {
      bfd *nbfd = _bfd_new_bfd_contained_in (archive);
      char *s = NULL;

      if (nbfd == NULL)
	return NULL;

      nbfd->origin = entry->offset;
      s = bfd_malloc (strlen (archive->filename) + 1);
      if (s == NULL)
	return NULL;
      strcpy (s, archive->filename);
      nbfd->filename = s;
      nbfd->iostream = NULL;
      entry->abfd = nbfd;
    }

  return entry->abfd;
}

int
bfd_mach_o_lookup_section (abfd, section, mcommand, msection)
     bfd *abfd;
     asection *section;
     bfd_mach_o_load_command **mcommand;
     bfd_mach_o_section **msection;
{
  struct mach_o_data_struct *md = abfd->tdata.mach_o_data;
  unsigned int i, j, num;

  bfd_mach_o_load_command *ncmd = NULL;
  bfd_mach_o_section *nsect = NULL;

  BFD_ASSERT (mcommand != NULL);
  BFD_ASSERT (msection != NULL);

  num = 0;
  for (i = 0; i < md->header.ncmds; i++)
    {
      struct bfd_mach_o_load_command *cmd = &md->commands[i];
      struct bfd_mach_o_segment_command *seg = NULL;

      if (cmd->type != BFD_MACH_O_LC_SEGMENT)
	continue;
      seg = &cmd->command.segment;

      if (seg->segment == section)
	{
	  if (num == 0)
	    ncmd = cmd;
	  num++;
	}

      for (j = 0; j < seg->nsects; j++)
	{
	  struct bfd_mach_o_section *sect = &seg->sections[j];

	  if (sect->bfdsection == section)
	    {
	      if (num == 0)
		nsect = sect;
	      num++;
	    }
	}
    }

  *mcommand = ncmd;
  *msection = nsect;
  return num;
}

int
bfd_mach_o_lookup_command (abfd, type, mcommand)
     bfd *abfd;
     bfd_mach_o_load_command_type type;
     bfd_mach_o_load_command **mcommand;
{
  struct mach_o_data_struct *md = NULL;
  bfd_mach_o_load_command *ncmd = NULL;
  unsigned int i, num;

  md = abfd->tdata.mach_o_data;

  BFD_ASSERT (md != NULL);
  BFD_ASSERT (mcommand != NULL);

  num = 0;
  for (i = 0; i < md->header.ncmds; i++)
    {
      struct bfd_mach_o_load_command *cmd = &md->commands[i];

      if (cmd->type != type)
	continue;

      if (num == 0)
	ncmd = cmd;
      num++;
    }

  *mcommand = ncmd;
  return num;
}

unsigned long
bfd_mach_o_stack_addr (type)
     enum bfd_mach_o_cpu_type type;
{
  switch (type)
    {
    case BFD_MACH_O_CPU_TYPE_MC680x0:
      return 0x04000000;
    case BFD_MACH_O_CPU_TYPE_MC88000:
      return 0xffffe000;
    case BFD_MACH_O_CPU_TYPE_POWERPC:
      return 0xc0000000;
    case BFD_MACH_O_CPU_TYPE_I386:
      return 0xc0000000;
    case BFD_MACH_O_CPU_TYPE_SPARC:
      return 0xf0000000;
    case BFD_MACH_O_CPU_TYPE_I860:
      return 0;
    case BFD_MACH_O_CPU_TYPE_HPPA:
      return 0xc0000000 - 0x04000000;
    default:
      return 0;
    }
}

int
bfd_mach_o_core_fetch_environment (abfd, rbuf, rlen)
     bfd *abfd;
     unsigned char **rbuf;
     unsigned int *rlen;
{
  bfd_mach_o_data_struct *mdata = abfd->tdata.mach_o_data;
  unsigned long stackaddr = bfd_mach_o_stack_addr (mdata->header.cputype);
  unsigned int i = 0;

  for (i = 0; i < mdata->header.ncmds; i++)
    {
      bfd_mach_o_load_command *cur = &mdata->commands[i];
      bfd_mach_o_segment_command *seg = NULL;

      if (cur->type != BFD_MACH_O_LC_SEGMENT)
	continue;

      seg = &cur->command.segment;

      if ((seg->vmaddr + seg->vmsize) == stackaddr)
	{
	  unsigned long start = seg->fileoff;
	  unsigned long end = seg->fileoff + seg->filesize;
	  unsigned char *buf = bfd_malloc (1024);
	  unsigned long size = 1024;

	  for (;;)
	    {
	      bfd_size_type nread = 0;
	      unsigned long offset;
	      int found_nonnull = 0;

	      if (size > (end - start))
		size = (end - start);

	      buf = bfd_realloc (buf, size);

	      bfd_seek (abfd, end - size, SEEK_SET);
	      nread = bfd_bread (buf, size, abfd);

	      if (nread != size)
		return -1;

	      for (offset = 4; offset <= size; offset += 4)
		{
		  unsigned long val;

		  val = *((unsigned long *) (buf + size - offset));
		  if (! found_nonnull)
		    {
		      if (val != 0)
			found_nonnull = 1;
		    }
		  else if (val == 0x0)
		    {
		      unsigned long bottom;
		      unsigned long top;

		      bottom = seg->fileoff + seg->filesize - offset;
		      top = seg->fileoff + seg->filesize - 4;
		      *rbuf = bfd_malloc (top - bottom);
		      *rlen = top - bottom;

		      memcpy (*rbuf, buf + size - *rlen, *rlen);
		      return 0;
		    }
		}

	      if (size == (end - start))
		break;

	      size *= 2;
	    }
	}
    }

  return -1;
}

char *
bfd_mach_o_core_file_failing_command (abfd)
     bfd *abfd;
{
  unsigned char *buf = NULL;
  unsigned int len = 0;
  int ret = -1;

  ret = bfd_mach_o_core_fetch_environment (abfd, &buf, &len);
  if (ret < 0)
    return NULL;

  return (char *) buf;
}

int
bfd_mach_o_core_file_failing_signal (abfd)
     bfd *abfd ATTRIBUTE_UNUSED;
{
  return 0;
}

bfd_boolean
bfd_mach_o_core_file_matches_executable_p (core_bfd, exec_bfd)
     bfd *core_bfd ATTRIBUTE_UNUSED;
     bfd *exec_bfd ATTRIBUTE_UNUSED;
{
  return TRUE;
}

#define TARGET_NAME mach_o_be_vec
#define TARGET_STRING "mach-o-be"
#define TARGET_BIG_ENDIAN 1
#define TARGET_ARCHIVE 0

#include "mach-o-target.c"

#undef TARGET_NAME
#undef TARGET_STRING
#undef TARGET_BIG_ENDIAN
#undef TARGET_ARCHIVE

#define TARGET_NAME mach_o_le_vec
#define TARGET_STRING "mach-o-le"
#define TARGET_BIG_ENDIAN 0
#define TARGET_ARCHIVE 0

#include "mach-o-target.c"

#undef TARGET_NAME
#undef TARGET_STRING
#undef TARGET_BIG_ENDIAN
#undef TARGET_ARCHIVE

#define TARGET_NAME mach_o_fat_vec
#define TARGET_STRING "mach-o-fat"
#define TARGET_BIG_ENDIAN 1
#define TARGET_ARCHIVE 1

#include "mach-o-target.c"

#undef TARGET_NAME
#undef TARGET_STRING
#undef TARGET_BIG_ENDIAN
#undef TARGET_ARCHIVE
