binutils-gdb/bfd/simple.c

280 lines
8.5 KiB
C

/* simple.c -- BFD simple client routines
Copyright (C) 2002-2017 Free Software Foundation, Inc.
Contributed by MontaVista Software, 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 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, write to the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
MA 02110-1301, USA. */
#include "sysdep.h"
#include "bfd.h"
#include "libbfd.h"
#include "bfdlink.h"
static void
simple_dummy_warning (struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
const char *warning ATTRIBUTE_UNUSED,
const char *symbol ATTRIBUTE_UNUSED,
bfd *abfd ATTRIBUTE_UNUSED,
asection *section ATTRIBUTE_UNUSED,
bfd_vma address ATTRIBUTE_UNUSED)
{
}
static void
simple_dummy_undefined_symbol (struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
const char *name ATTRIBUTE_UNUSED,
bfd *abfd ATTRIBUTE_UNUSED,
asection *section ATTRIBUTE_UNUSED,
bfd_vma address ATTRIBUTE_UNUSED,
bfd_boolean fatal ATTRIBUTE_UNUSED)
{
}
static void
simple_dummy_reloc_overflow (struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
struct bfd_link_hash_entry *entry ATTRIBUTE_UNUSED,
const char *name ATTRIBUTE_UNUSED,
const char *reloc_name ATTRIBUTE_UNUSED,
bfd_vma addend ATTRIBUTE_UNUSED,
bfd *abfd ATTRIBUTE_UNUSED,
asection *section ATTRIBUTE_UNUSED,
bfd_vma address ATTRIBUTE_UNUSED)
{
}
static void
simple_dummy_reloc_dangerous (struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
const char *message ATTRIBUTE_UNUSED,
bfd *abfd ATTRIBUTE_UNUSED,
asection *section ATTRIBUTE_UNUSED,
bfd_vma address ATTRIBUTE_UNUSED)
{
}
static void
simple_dummy_unattached_reloc (struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
const char *name ATTRIBUTE_UNUSED,
bfd *abfd ATTRIBUTE_UNUSED,
asection *section ATTRIBUTE_UNUSED,
bfd_vma address ATTRIBUTE_UNUSED)
{
}
static void
simple_dummy_multiple_definition (struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
struct bfd_link_hash_entry *h ATTRIBUTE_UNUSED,
bfd *nbfd ATTRIBUTE_UNUSED,
asection *nsec ATTRIBUTE_UNUSED,
bfd_vma nval ATTRIBUTE_UNUSED)
{
}
static void
simple_dummy_einfo (const char *fmt ATTRIBUTE_UNUSED, ...)
{
}
struct saved_output_info
{
bfd_vma offset;
asection *section;
};
struct saved_offsets
{
unsigned int section_count;
struct saved_output_info *sections;
};
/* The sections in ABFD may already have output sections and offsets
set if we are here during linking.
DWARF-2 specifies offsets into debug sections in many cases and
bfd_simple_get_relocated_section_contents is called to relocate
debug info for a single relocatable object file. So we want
offsets relative to that object file's sections, not offsets in the
output file. For that reason, reset a debug section->output_offset
to zero.
If not called during linking then set section->output_section to
point back to the input section, because output_section must not be
NULL when calling the relocation routines.
Save the original output offset and section to restore later. */
static void
simple_save_output_info (bfd *abfd ATTRIBUTE_UNUSED,
asection *section,
void *ptr)
{
struct saved_offsets *saved_offsets = (struct saved_offsets *) ptr;
struct saved_output_info *output_info;
output_info = &saved_offsets->sections[section->index];
output_info->offset = section->output_offset;
output_info->section = section->output_section;
if ((section->flags & SEC_DEBUGGING) != 0
|| section->output_section == NULL)
{
section->output_offset = 0;
section->output_section = section;
}
}
static void
simple_restore_output_info (bfd *abfd ATTRIBUTE_UNUSED,
asection *section,
void *ptr)
{
struct saved_offsets *saved_offsets = (struct saved_offsets *) ptr;
struct saved_output_info *output_info;
if (section->index >= saved_offsets->section_count)
return;
output_info = &saved_offsets->sections[section->index];
section->output_offset = output_info->offset;
section->output_section = output_info->section;
}
/*
FUNCTION
bfd_simple_relocate_secton
SYNOPSIS
bfd_byte *bfd_simple_get_relocated_section_contents
(bfd *abfd, asection *sec, bfd_byte *outbuf, asymbol **symbol_table);
DESCRIPTION
Returns the relocated contents of section @var{sec}. The symbols in
@var{symbol_table} will be used, or the symbols from @var{abfd} if
@var{symbol_table} is NULL. The output offsets for debug sections will
be temporarily reset to 0. The result will be stored at @var{outbuf}
or allocated with @code{bfd_malloc} if @var{outbuf} is @code{NULL}.
Returns @code{NULL} on a fatal error; ignores errors applying
particular relocations.
*/
bfd_byte *
bfd_simple_get_relocated_section_contents (bfd *abfd,
asection *sec,
bfd_byte *outbuf,
asymbol **symbol_table)
{
struct bfd_link_info link_info;
struct bfd_link_order link_order;
struct bfd_link_callbacks callbacks;
bfd_byte *contents, *data;
int storage_needed;
struct saved_offsets saved_offsets;
bfd *link_next;
/* Don't apply relocation on executable and shared library. See
PR 4756. */
if ((abfd->flags & (HAS_RELOC | EXEC_P | DYNAMIC)) != HAS_RELOC
|| ! (sec->flags & SEC_RELOC))
{
contents = outbuf;
if (!bfd_get_full_section_contents (abfd, sec, &contents))
return NULL;
return contents;
}
/* In order to use bfd_get_relocated_section_contents, we need
to forge some data structures that it expects. */
/* Fill in the bare minimum number of fields for our purposes. */
memset (&link_info, 0, sizeof (link_info));
link_info.output_bfd = abfd;
link_info.input_bfds = abfd;
link_info.input_bfds_tail = &abfd->link.next;
link_next = abfd->link.next;
abfd->link.next = NULL;
link_info.hash = _bfd_generic_link_hash_table_create (abfd);
link_info.callbacks = &callbacks;
callbacks.warning = simple_dummy_warning;
callbacks.undefined_symbol = simple_dummy_undefined_symbol;
callbacks.reloc_overflow = simple_dummy_reloc_overflow;
callbacks.reloc_dangerous = simple_dummy_reloc_dangerous;
callbacks.unattached_reloc = simple_dummy_unattached_reloc;
callbacks.multiple_definition = simple_dummy_multiple_definition;
callbacks.einfo = simple_dummy_einfo;
memset (&link_order, 0, sizeof (link_order));
link_order.next = NULL;
link_order.type = bfd_indirect_link_order;
link_order.offset = 0;
link_order.size = sec->size;
link_order.u.indirect.section = sec;
data = NULL;
if (outbuf == NULL)
{
bfd_size_type amt = sec->rawsize > sec->size ? sec->rawsize : sec->size;
data = (bfd_byte *) bfd_malloc (amt);
if (data == NULL)
{
_bfd_generic_link_hash_table_free (abfd);
abfd->link.next = link_next;
return NULL;
}
outbuf = data;
}
saved_offsets.section_count = abfd->section_count;
saved_offsets.sections = malloc (sizeof (*saved_offsets.sections)
* saved_offsets.section_count);
if (saved_offsets.sections == NULL)
{
if (data)
free (data);
_bfd_generic_link_hash_table_free (abfd);
abfd->link.next = link_next;
return NULL;
}
bfd_map_over_sections (abfd, simple_save_output_info, &saved_offsets);
if (symbol_table == NULL)
{
_bfd_generic_link_add_symbols (abfd, &link_info);
storage_needed = bfd_get_symtab_upper_bound (abfd);
symbol_table = (asymbol **) bfd_malloc (storage_needed);
bfd_canonicalize_symtab (abfd, symbol_table);
}
else
storage_needed = 0;
contents = bfd_get_relocated_section_contents (abfd,
&link_info,
&link_order,
outbuf,
0,
symbol_table);
if (contents == NULL && data != NULL)
free (data);
bfd_map_over_sections (abfd, simple_restore_output_info, &saved_offsets);
free (saved_offsets.sections);
_bfd_generic_link_hash_table_free (abfd);
abfd->link.next = link_next;
return contents;
}