Coverage Report

Created: 2025-06-24 06:45

/src/binutils-gdb/bfd/binary.c
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/* BFD back-end for binary objects.
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   Copyright (C) 1994-2025 Free Software Foundation, Inc.
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   Written by Ian Lance Taylor, Cygnus Support, <ian@cygnus.com>
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   This file is part of BFD, the Binary File Descriptor library.
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   This program is free software; you can redistribute it and/or modify
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   it under the terms of the GNU General Public License as published by
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   the Free Software Foundation; either version 3 of the License, or
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   (at your option) any later version.
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   This program is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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   GNU General Public License for more details.
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   You should have received a copy of the GNU General Public License
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   along with this program; if not, write to the Free Software
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   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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   MA 02110-1301, USA.  */
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/* This is a BFD backend which may be used to read or write binary
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   objects.  Historically, it was used as an output format for objcopy
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   in order to generate raw binary data, but is now used for other
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   purposes as well.
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   This is very simple.  The only complication is that the real data
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   will start at some address X, and in some cases we will not want to
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   include X zeroes just to get to that point.  Since the start
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   address is not meaningful for this object file format, we use it
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   instead to indicate the number of zeroes to skip at the start of
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   the file.  objcopy cooperates by specially setting the start
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   address to zero by default.  */
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#include "sysdep.h"
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#include "bfd.h"
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#include "safe-ctype.h"
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#include "libbfd.h"
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/* Any bfd we create by reading a binary file has three symbols:
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   a start symbol, an end symbol, and an absolute length symbol.  */
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0
#define BIN_SYMS 3
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/* Create a binary object.  Invoked via bfd_set_format.  */
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static bool
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binary_mkobject (bfd *abfd ATTRIBUTE_UNUSED)
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0
{
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0
  return true;
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0
}
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/* Any file may be considered to be a binary file, provided the target
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   was not defaulted.  That is, it must be explicitly specified as
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   being binary.  */
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static bfd_cleanup
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binary_object_p (bfd *abfd)
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0
{
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0
  struct stat statbuf;
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0
  asection *sec;
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0
  flagword flags;
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0
  if (abfd->target_defaulted)
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0
    {
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0
      bfd_set_error (bfd_error_wrong_format);
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0
      return NULL;
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0
    }
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0
  abfd->symcount = BIN_SYMS;
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  /* Find the file size.  */
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0
  if (bfd_stat (abfd, &statbuf) < 0)
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0
    {
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0
      bfd_set_error (bfd_error_system_call);
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0
      return NULL;
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0
    }
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  /* One data section.  */
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0
  flags = SEC_ALLOC | SEC_LOAD | SEC_DATA | SEC_HAS_CONTENTS;
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0
  sec = bfd_make_section_with_flags (abfd, ".data", flags);
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0
  if (sec == NULL)
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0
    return NULL;
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0
  sec->vma = 0;
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0
  sec->size = statbuf.st_size;
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  sec->filepos = 0;
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  abfd->tdata.any = (void *) sec;
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  return _bfd_no_cleanup;
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0
}
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#define binary_close_and_cleanup     _bfd_generic_close_and_cleanup
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#define binary_bfd_free_cached_info  _bfd_generic_bfd_free_cached_info
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#define binary_new_section_hook      _bfd_generic_new_section_hook
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/* Get contents of the only section.  */
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static bool
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binary_get_section_contents (bfd *abfd,
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           asection *section,
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           void * location,
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           file_ptr offset,
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           bfd_size_type count)
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0
{
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0
  if (bfd_seek (abfd, section->filepos + offset, SEEK_SET) != 0
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0
      || bfd_read (location, count, abfd) != count)
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    return false;
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  return true;
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0
}
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/* Return the amount of memory needed to read the symbol table.  */
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static long
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binary_get_symtab_upper_bound (bfd *abfd ATTRIBUTE_UNUSED)
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0
{
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  return (BIN_SYMS + 1) * sizeof (asymbol *);
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0
}
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/* Create a symbol name based on the bfd's filename.  */
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static char *
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mangle_name (bfd *abfd, char *suffix)
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0
{
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  bfd_size_type size;
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  char *buf;
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  char *p;
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  size = (strlen (bfd_get_filename (abfd))
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    + strlen (suffix)
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0
    + sizeof "_binary__");
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  buf = (char *) bfd_alloc (abfd, size);
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  if (buf == NULL)
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    return "";
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  sprintf (buf, "_binary_%s_%s", bfd_get_filename (abfd), suffix);
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  /* Change any non-alphanumeric characters to underscores.  */
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  for (p = buf; *p; p++)
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    if (! ISALNUM (*p))
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      *p = '_';
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  return buf;
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0
}
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/* Return the symbol table.  */
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static long
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binary_canonicalize_symtab (bfd *abfd, asymbol **alocation)
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0
{
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  asection *sec = (asection *) abfd->tdata.any;
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  asymbol *syms;
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  unsigned int i;
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  size_t amt = BIN_SYMS * sizeof (asymbol);
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  syms = (asymbol *) bfd_alloc (abfd, amt);
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  if (syms == NULL)
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    return -1;
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  /* Start symbol.  */
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  syms[0].the_bfd = abfd;
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  syms[0].name = mangle_name (abfd, "start");
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  syms[0].value = 0;
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  syms[0].flags = BSF_GLOBAL;
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  syms[0].section = sec;
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  syms[0].udata.p = NULL;
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  /* End symbol.  */
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  syms[1].the_bfd = abfd;
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  syms[1].name = mangle_name (abfd, "end");
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  syms[1].value = sec->size;
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  syms[1].flags = BSF_GLOBAL;
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  syms[1].section = sec;
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  syms[1].udata.p = NULL;
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  /* Size symbol.  */
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  syms[2].the_bfd = abfd;
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  syms[2].name = mangle_name (abfd, "size");
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  syms[2].value = sec->size;
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  syms[2].flags = BSF_GLOBAL;
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  syms[2].section = bfd_abs_section_ptr;
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  syms[2].udata.p = NULL;
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  for (i = 0; i < BIN_SYMS; i++)
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    *alocation++ = syms++;
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  *alocation = NULL;
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  return BIN_SYMS;
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0
}
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#define binary_make_empty_symbol  _bfd_generic_make_empty_symbol
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#define binary_print_symbol       _bfd_nosymbols_print_symbol
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#define binary_get_symbol_version_string \
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  _bfd_nosymbols_get_symbol_version_string
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/* Get information about a symbol.  */
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static void
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binary_get_symbol_info (bfd *ignore_abfd ATTRIBUTE_UNUSED,
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      asymbol *symbol,
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      symbol_info *ret)
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0
{
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  bfd_symbol_info (symbol, ret);
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0
}
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#define binary_bfd_is_local_label_name      bfd_generic_is_local_label_name
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#define binary_get_lineno      _bfd_nosymbols_get_lineno
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#define binary_find_nearest_line     _bfd_nosymbols_find_nearest_line
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#define binary_find_nearest_line_with_alt  _bfd_nosymbols_find_nearest_line_with_alt
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#define binary_find_line       _bfd_nosymbols_find_line
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#define binary_find_inliner_info     _bfd_nosymbols_find_inliner_info
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#define binary_bfd_make_debug_symbol     _bfd_nosymbols_bfd_make_debug_symbol
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#define binary_read_minisymbols      _bfd_generic_read_minisymbols
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#define binary_minisymbol_to_symbol    _bfd_generic_minisymbol_to_symbol
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#define binary_bfd_is_target_special_symbol _bfd_bool_bfd_asymbol_false
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/* Set the architecture of a binary file.  */
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#define binary_set_arch_mach _bfd_generic_set_arch_mach
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/* Write section contents of a binary file.  */
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static bool
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binary_set_section_contents (bfd *abfd,
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           asection *sec,
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           const void * data,
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           file_ptr offset,
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           bfd_size_type size)
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0
{
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0
  if (size == 0)
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    return true;
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  if (! abfd->output_has_begun)
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0
    {
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0
      bool found_low;
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      bfd_vma low;
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      asection *s;
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      /* The lowest section LMA sets the virtual address of the start
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   of the file.  We use this to set the file position of all the
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   sections.  */
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      found_low = false;
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      low = 0;
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      for (s = abfd->sections; s != NULL; s = s->next)
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  if (((s->flags
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        & (SEC_HAS_CONTENTS | SEC_LOAD | SEC_ALLOC | SEC_NEVER_LOAD))
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       == (SEC_HAS_CONTENTS | SEC_LOAD | SEC_ALLOC))
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      && (s->size > 0)
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      && (! found_low || s->lma < low))
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    {
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      low = s->lma;
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      found_low = true;
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    }
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      for (s = abfd->sections; s != NULL; s = s->next)
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  {
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0
    unsigned int opb = bfd_octets_per_byte (abfd, s);
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    s->filepos = (s->lma - low) * opb;
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    /* Skip following warning check for sections that will not
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       occupy file space.  */
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    if ((s->flags
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0
         & (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_NEVER_LOAD))
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        != (SEC_HAS_CONTENTS | SEC_ALLOC)
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        || (s->size == 0))
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0
      continue;
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    /* If attempting to generate a binary file from a bfd with
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       LMA's all over the place, huge (sparse?) binary files may
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       result.  This condition attempts to detect this situation
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       and print a warning.  Better heuristics would be nice to
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       have.  */
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0
    if (s->filepos < 0)
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      _bfd_error_handler
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        /* xgettext:c-format */
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0
        (_("warning: writing section `%pA' at huge (ie negative) "
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0
     "file offset"),
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0
         s);
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  }
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      abfd->output_has_begun = true;
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0
    }
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  /* We don't want to output anything for a section that is neither
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     loaded nor allocated.  The contents of such a section are not
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     meaningful in the binary format.  */
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  if ((sec->flags & (SEC_LOAD | SEC_ALLOC)) == 0)
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    return true;
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  if ((sec->flags & SEC_NEVER_LOAD) != 0)
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    return true;
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  return _bfd_generic_set_section_contents (abfd, sec, data, offset, size);
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0
}
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#define binary_sizeof_headers        _bfd_nolink_sizeof_headers
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#define binary_bfd_get_relocated_section_contents  bfd_generic_get_relocated_section_contents
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#define binary_bfd_relax_section       bfd_generic_relax_section
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#define binary_bfd_gc_sections         bfd_generic_gc_sections
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#define binary_bfd_lookup_section_flags      bfd_generic_lookup_section_flags
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#define binary_bfd_merge_sections      bfd_generic_merge_sections
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#define binary_bfd_is_group_section      bfd_generic_is_group_section
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#define binary_bfd_group_name        bfd_generic_group_name
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#define binary_bfd_discard_group       bfd_generic_discard_group
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#define binary_section_already_linked     _bfd_generic_section_already_linked
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#define binary_bfd_define_common_symbol      bfd_generic_define_common_symbol
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#define binary_bfd_link_hide_symbol      _bfd_generic_link_hide_symbol
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#define binary_bfd_define_start_stop       bfd_generic_define_start_stop
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#define binary_bfd_link_hash_table_create   _bfd_generic_link_hash_table_create
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#define binary_bfd_link_just_syms     _bfd_generic_link_just_syms
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#define binary_bfd_copy_link_hash_symbol_type   _bfd_generic_copy_link_hash_symbol_type
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#define binary_bfd_link_add_symbols     _bfd_generic_link_add_symbols
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#define binary_bfd_final_link       _bfd_generic_final_link
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#define binary_bfd_link_split_section     _bfd_generic_link_split_section
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#define binary_bfd_link_check_relocs      _bfd_generic_link_check_relocs
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const bfd_target binary_vec =
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{
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  "binary",     /* name */
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  bfd_target_unknown_flavour, /* flavour */
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  BFD_ENDIAN_UNKNOWN,   /* byteorder */
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  BFD_ENDIAN_UNKNOWN,   /* header_byteorder */
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  EXEC_P,     /* object_flags */
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  (SEC_CODE | SEC_DATA | SEC_ROM | SEC_HAS_CONTENTS
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   | SEC_ALLOC | SEC_LOAD), /* section_flags */
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  0,        /* symbol_leading_char */
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  ' ',        /* ar_pad_char */
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  16,       /* ar_max_namelen */
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  255,        /* match priority.  */
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  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
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  bfd_getb64, bfd_getb_signed_64, bfd_putb64,
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  bfd_getb32, bfd_getb_signed_32, bfd_putb32,
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  bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */
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  bfd_getb64, bfd_getb_signed_64, bfd_putb64,
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  bfd_getb32, bfd_getb_signed_32, bfd_putb32,
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  bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */
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  {       /* bfd_check_format */
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    _bfd_dummy_target,
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    binary_object_p,
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    _bfd_dummy_target,
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    _bfd_dummy_target,
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  },
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  {       /* bfd_set_format */
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    _bfd_bool_bfd_false_error,
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    binary_mkobject,
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    _bfd_bool_bfd_false_error,
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    _bfd_bool_bfd_false_error,
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  },
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  {       /* bfd_write_contents */
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    _bfd_bool_bfd_false_error,
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    _bfd_bool_bfd_true,
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    _bfd_bool_bfd_false_error,
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    _bfd_bool_bfd_false_error,
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  },
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  BFD_JUMP_TABLE_GENERIC (binary),
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  BFD_JUMP_TABLE_COPY (_bfd_generic),
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  BFD_JUMP_TABLE_CORE (_bfd_nocore),
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  BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
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  BFD_JUMP_TABLE_SYMBOLS (binary),
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  BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
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  BFD_JUMP_TABLE_WRITE (binary),
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  BFD_JUMP_TABLE_LINK (binary),
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  BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
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  NULL,
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  NULL
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};