[thirdparty/binutils-gdb.git] / bfd / simple.c

/* simple.c -- BFD simple client routines
   Copyright (C) 2002-2024 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"
#include "genlink.h"

static void
simple_dummy_add_to_set (struct bfd_link_info * info ATTRIBUTE_UNUSED,
			 struct bfd_link_hash_entry *entry ATTRIBUTE_UNUSED,
			 bfd_reloc_code_real_type reloc ATTRIBUTE_UNUSED,
			 bfd *abfd ATTRIBUTE_UNUSED,
			 asection *sec ATTRIBUTE_UNUSED,
			 bfd_vma value ATTRIBUTE_UNUSED)
{
}

static  void
simple_dummy_constructor (struct bfd_link_info * info ATTRIBUTE_UNUSED,
			  bool constructor ATTRIBUTE_UNUSED,
			  const char *name ATTRIBUTE_UNUSED,
			  bfd *abfd ATTRIBUTE_UNUSED,
			  asection *sec ATTRIBUTE_UNUSED,
			  bfd_vma value ATTRIBUTE_UNUSED)
{
}

static void
simple_dummy_multiple_common (struct bfd_link_info * info ATTRIBUTE_UNUSED,
			      struct bfd_link_hash_entry * entry ATTRIBUTE_UNUSED,
			      bfd * abfd ATTRIBUTE_UNUSED,
			      enum bfd_link_hash_type type ATTRIBUTE_UNUSED,
			      bfd_vma size ATTRIBUTE_UNUSED)
{
}

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,
			       bool 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;
  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))
    {
      if (!bfd_get_full_section_contents (abfd, sec, &outbuf))
	return NULL;
      return outbuf;
    }

  /* 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;
  /* Make sure that any fields not initialised below do not
     result in a potential indirection via a random address.  */
  memset (&callbacks, 0, sizeof 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;
  callbacks.multiple_common = simple_dummy_multiple_common;
  callbacks.constructor = simple_dummy_constructor;
  callbacks.add_to_set = simple_dummy_add_to_set;

  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;

  contents = NULL;

  saved_offsets.section_count = abfd->section_count;
  saved_offsets.sections = malloc (sizeof (*saved_offsets.sections)
				   * saved_offsets.section_count);
  if (saved_offsets.sections == NULL)
    goto out1;
  bfd_map_over_sections (abfd, simple_save_output_info, &saved_offsets);

  if (symbol_table == NULL)
    {
      if (!bfd_generic_link_read_symbols (abfd))
	goto out2;
      symbol_table = _bfd_generic_link_get_symbols (abfd);
    }

  contents = bfd_get_relocated_section_contents (abfd,
						 &link_info,
						 &link_order,
						 outbuf,
						 false,
						 symbol_table);
 out2:
  bfd_map_over_sections (abfd, simple_restore_output_info, &saved_offsets);
  free (saved_offsets.sections);
 out1:
  _bfd_generic_link_hash_table_free (abfd);
  abfd->link.next = link_next;
  return contents;
}
Commit	Line	Data
af39267e	1	/* simple.c -- BFD simple client routines
fd67aa11	2	Copyright (C) 2002-2024 Free Software Foundation, Inc.
af39267e DJ	3	Contributed by MontaVista Software, Inc.
	4
	5	This file is part of BFD, the Binary File Descriptor library.
	6
	7	This program is free software; you can redistribute it and/or modify
	8	it under the terms of the GNU General Public License as published by
cd123cb7	9	the Free Software Foundation; either version 3 of the License, or
af39267e DJ	10	(at your option) any later version.
	11
	12	This program is distributed in the hope that it will be useful,
	13	but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	GNU General Public License for more details.
	16
	17	You should have received a copy of the GNU General Public License
	18	along with this program; if not, write to the Free Software
cd123cb7 NC	19	Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
cd123cb7 NC	20	MA 02110-1301, USA. */
af39267e	21
af39267e	22	#include "sysdep.h"
3db64b00	23	#include "bfd.h"
af39267e DJ	24	#include "libbfd.h"
af39267e DJ	25	#include "bfdlink.h"
77491337	26	#include "genlink.h"
af39267e	27
23182ac0 NC	28	static void
	29	simple_dummy_add_to_set (struct bfd_link_info * info ATTRIBUTE_UNUSED,
	30	struct bfd_link_hash_entry *entry ATTRIBUTE_UNUSED,
	31	bfd_reloc_code_real_type reloc ATTRIBUTE_UNUSED,
	32	bfd *abfd ATTRIBUTE_UNUSED,
	33	asection *sec ATTRIBUTE_UNUSED,
	34	bfd_vma value ATTRIBUTE_UNUSED)
	35	{
	36	}
	37
	38	static void
	39	simple_dummy_constructor (struct bfd_link_info * info ATTRIBUTE_UNUSED,
	40	bool constructor ATTRIBUTE_UNUSED,
	41	const char *name ATTRIBUTE_UNUSED,
	42	bfd *abfd ATTRIBUTE_UNUSED,
	43	asection *sec ATTRIBUTE_UNUSED,
	44	bfd_vma value ATTRIBUTE_UNUSED)
	45	{
	46	}
	47
	48	static void
	49	simple_dummy_multiple_common (struct bfd_link_info * info ATTRIBUTE_UNUSED,
	50	struct bfd_link_hash_entry * entry ATTRIBUTE_UNUSED,
	51	bfd * abfd ATTRIBUTE_UNUSED,
	52	enum bfd_link_hash_type type ATTRIBUTE_UNUSED,
	53	bfd_vma size ATTRIBUTE_UNUSED)
	54	{
	55	}
	56
1a72702b	57	static void
c58b9523 AM	58	simple_dummy_warning (struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
	59	const char *warning ATTRIBUTE_UNUSED,
	60	const char *symbol ATTRIBUTE_UNUSED,
	61	bfd *abfd ATTRIBUTE_UNUSED,
	62	asection *section ATTRIBUTE_UNUSED,
	63	bfd_vma address ATTRIBUTE_UNUSED)
af39267e	64	{
af39267e DJ	65	}
af39267e DJ	66
1a72702b	67	static void
c58b9523 AM	68	simple_dummy_undefined_symbol (struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
	69	const char *name ATTRIBUTE_UNUSED,
	70	bfd *abfd ATTRIBUTE_UNUSED,
	71	asection *section ATTRIBUTE_UNUSED,
	72	bfd_vma address ATTRIBUTE_UNUSED,
0a1b45a2	73	bool fatal ATTRIBUTE_UNUSED)
af39267e	74	{
af39267e DJ	75	}
af39267e DJ	76
1a72702b	77	static void
c58b9523	78	simple_dummy_reloc_overflow (struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
dfeffb9f	79	struct bfd_link_hash_entry *entry ATTRIBUTE_UNUSED,
c58b9523 AM	80	const char *name ATTRIBUTE_UNUSED,
	81	const char *reloc_name ATTRIBUTE_UNUSED,
	82	bfd_vma addend ATTRIBUTE_UNUSED,
	83	bfd *abfd ATTRIBUTE_UNUSED,
	84	asection *section ATTRIBUTE_UNUSED,
	85	bfd_vma address ATTRIBUTE_UNUSED)
af39267e	86	{
af39267e DJ	87	}
af39267e DJ	88
1a72702b	89	static void
c58b9523 AM	90	simple_dummy_reloc_dangerous (struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
	91	const char *message ATTRIBUTE_UNUSED,
	92	bfd *abfd ATTRIBUTE_UNUSED,
	93	asection *section ATTRIBUTE_UNUSED,
	94	bfd_vma address ATTRIBUTE_UNUSED)
af39267e	95	{
af39267e DJ	96	}
af39267e DJ	97
1a72702b	98	static void
c58b9523 AM	99	simple_dummy_unattached_reloc (struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
	100	const char *name ATTRIBUTE_UNUSED,
	101	bfd *abfd ATTRIBUTE_UNUSED,
	102	asection *section ATTRIBUTE_UNUSED,
	103	bfd_vma address ATTRIBUTE_UNUSED)
af39267e	104	{
af39267e DJ	105	}
af39267e DJ	106
1a72702b	107	static void
1511ddaf	108	simple_dummy_multiple_definition (struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
24f58f47	109	struct bfd_link_hash_entry *h ATTRIBUTE_UNUSED,
1511ddaf DJ	110	bfd *nbfd ATTRIBUTE_UNUSED,
	111	asection *nsec ATTRIBUTE_UNUSED,
	112	bfd_vma nval ATTRIBUTE_UNUSED)
	113	{
1511ddaf DJ	114	}
1511ddaf DJ	115
e1fffbe6 AM	116	static void
	117	simple_dummy_einfo (const char *fmt ATTRIBUTE_UNUSED, ...)
	118	{
	119	}
	120
6e84a906 DJ	121	struct saved_output_info
	122	{
	123	bfd_vma offset;
	124	asection *section;
	125	};
	126
024a2310 JK	127	struct saved_offsets
024a2310 JK	128	{
7292b3ac	129	unsigned int section_count;
024a2310 JK	130	struct saved_output_info *sections;
	131	};
	132
93ee1e36 AM	133	/* The sections in ABFD may already have output sections and offsets
	134	set if we are here during linking.
	135
	136	DWARF-2 specifies offsets into debug sections in many cases and
	137	bfd_simple_get_relocated_section_contents is called to relocate
	138	debug info for a single relocatable object file. So we want
	139	offsets relative to that object file's sections, not offsets in the
	140	output file. For that reason, reset a debug section->output_offset
	141	to zero.
	142
	143	If not called during linking then set section->output_section to
	144	point back to the input section, because output_section must not be
	145	NULL when calling the relocation routines.
	146
	147	Save the original output offset and section to restore later. */
	148
6e84a906	149	static void
c58b9523 AM	150	simple_save_output_info (bfd *abfd ATTRIBUTE_UNUSED,
	151	asection *section,
	152	void *ptr)
6e84a906	153	{
024a2310 JK	154	struct saved_offsets saved_offsets = (struct saved_offsets ) ptr;
	155	struct saved_output_info *output_info;
	156
	157	output_info = &saved_offsets->sections[section->index];
	158	output_info->offset = section->output_offset;
	159	output_info->section = section->output_section;
1ba54ee0 AM	160	if ((section->flags & SEC_DEBUGGING) != 0
	161	\|\| section->output_section == NULL)
	162	{
	163	section->output_offset = 0;
	164	section->output_section = section;
	165	}
6e84a906 DJ	166	}
	167
	168	static void
c58b9523 AM	169	simple_restore_output_info (bfd *abfd ATTRIBUTE_UNUSED,
	170	asection *section,
	171	void *ptr)
6e84a906	172	{
024a2310 JK	173	struct saved_offsets saved_offsets = (struct saved_offsets ) ptr;
	174	struct saved_output_info *output_info;
	175
	176	if (section->index >= saved_offsets->section_count)
	177	return;
	178
	179	output_info = &saved_offsets->sections[section->index];
	180	section->output_offset = output_info->offset;
	181	section->output_section = output_info->section;
6e84a906 DJ	182	}
6e84a906 DJ	183
af39267e DJ	184	/*
	185	FUNCTION
	186	bfd_simple_relocate_secton
	187
	188	SYNOPSIS
c58b9523 AM	189	bfd_byte *bfd_simple_get_relocated_section_contents
c58b9523 AM	190	(bfd abfd, asection sec, bfd_byte outbuf, asymbol *symbol_table);
af39267e DJ	191
af39267e DJ	192	DESCRIPTION
6e84a906 DJ	193	Returns the relocated contents of section @var{sec}. The symbols in
6e84a906 DJ	194	@var{symbol_table} will be used, or the symbols from @var{abfd} if
1ba54ee0	195	@var{symbol_table} is NULL. The output offsets for debug sections will
6e84a906	196	be temporarily reset to 0. The result will be stored at @var{outbuf}
af39267e DJ	197	or allocated with @code{bfd_malloc} if @var{outbuf} is @code{NULL}.
af39267e DJ	198
af39267e DJ	199	Returns @code{NULL} on a fatal error; ignores errors applying
	200	particular relocations.
	201	*/
	202
	203	bfd_byte *
c58b9523 AM	204	bfd_simple_get_relocated_section_contents (bfd *abfd,
	205	asection *sec,
	206	bfd_byte *outbuf,
	207	asymbol **symbol_table)
af39267e DJ	208	{
	209	struct bfd_link_info link_info;
	210	struct bfd_link_order link_order;
	211	struct bfd_link_callbacks callbacks;
56ba7527	212	bfd_byte *contents;
024a2310	213	struct saved_offsets saved_offsets;
d495ab0d	214	bfd *link_next;
af39267e	215
329b43c4 L	216	/* Don't apply relocation on executable and shared library. See
	217	PR 4756. */
	218	if ((abfd->flags & (HAS_RELOC \| EXEC_P \| DYNAMIC)) != HAS_RELOC
	219	\|\| ! (sec->flags & SEC_RELOC))
ec4530b5	220	{
77491337	221	if (!bfd_get_full_section_contents (abfd, sec, &outbuf))
4a114e3e	222	return NULL;
77491337	223	return outbuf;
ec4530b5 NC	224	}
ec4530b5 NC	225
af39267e DJ	226	/* In order to use bfd_get_relocated_section_contents, we need
	227	to forge some data structures that it expects. */
	228
	229	/* Fill in the bare minimum number of fields for our purposes. */
	230	memset (&link_info, 0, sizeof (link_info));
37da76e8	231	link_info.output_bfd = abfd;
af39267e	232	link_info.input_bfds = abfd;
c72f2fb2	233	link_info.input_bfds_tail = &abfd->link.next;
af39267e	234
d495ab0d AM	235	link_next = abfd->link.next;
d495ab0d AM	236	abfd->link.next = NULL;
228ce064	237	link_info.hash = _bfd_generic_link_hash_table_create (abfd);
af39267e	238	link_info.callbacks = &callbacks;
23182ac0 NC	239	/* Make sure that any fields not initialised below do not
	240	result in a potential indirection via a random address. */
	241	memset (&callbacks, 0, sizeof callbacks);
af39267e DJ	242	callbacks.warning = simple_dummy_warning;
	243	callbacks.undefined_symbol = simple_dummy_undefined_symbol;
	244	callbacks.reloc_overflow = simple_dummy_reloc_overflow;
	245	callbacks.reloc_dangerous = simple_dummy_reloc_dangerous;
	246	callbacks.unattached_reloc = simple_dummy_unattached_reloc;
1511ddaf	247	callbacks.multiple_definition = simple_dummy_multiple_definition;
e1fffbe6	248	callbacks.einfo = simple_dummy_einfo;
23182ac0 NC	249	callbacks.multiple_common = simple_dummy_multiple_common;
	250	callbacks.constructor = simple_dummy_constructor;
	251	callbacks.add_to_set = simple_dummy_add_to_set;
af39267e DJ	252
	253	memset (&link_order, 0, sizeof (link_order));
	254	link_order.next = NULL;
	255	link_order.type = bfd_indirect_link_order;
	256	link_order.offset = 0;
eea6121a	257	link_order.size = sec->size;
af39267e DJ	258	link_order.u.indirect.section = sec;
af39267e DJ	259
77491337	260	contents = NULL;
af39267e	261
024a2310 JK	262	saved_offsets.section_count = abfd->section_count;
	263	saved_offsets.sections = malloc (sizeof (*saved_offsets.sections)
	264	* saved_offsets.section_count);
	265	if (saved_offsets.sections == NULL)
56ba7527	266	goto out1;
024a2310	267	bfd_map_over_sections (abfd, simple_save_output_info, &saved_offsets);
6e84a906 DJ	268
	269	if (symbol_table == NULL)
	270	{
77491337	271	if (!bfd_generic_link_read_symbols (abfd))
56ba7527	272	goto out2;
77491337	273	symbol_table = _bfd_generic_link_get_symbols (abfd);
6e84a906	274	}
af39267e DJ	275
	276	contents = bfd_get_relocated_section_contents (abfd,
	277	&link_info,
	278	&link_order,
	279	outbuf,
77491337	280	false,
af39267e	281	symbol_table);
56ba7527	282	out2:
024a2310 JK	283	bfd_map_over_sections (abfd, simple_restore_output_info, &saved_offsets);
024a2310 JK	284	free (saved_offsets.sections);
77491337	285	out1:
d495ab0d AM	286	_bfd_generic_link_hash_table_free (abfd);
d495ab0d AM	287	abfd->link.next = link_next;
57a1784e	288	return contents;
af39267e	289	}