123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377 |
- /* BFD back-end for binary objects.
- Copyright (C) 1994-2022 Free Software Foundation, Inc.
- Written by Ian Lance Taylor, Cygnus Support, <ian@cygnus.com>
- 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. */
- /* This is a BFD backend which may be used to read or write binary
- objects. Historically, it was used as an output format for objcopy
- in order to generate raw binary data, but is now used for other
- purposes as well.
- This is very simple. The only complication is that the real data
- will start at some address X, and in some cases we will not want to
- include X zeroes just to get to that point. Since the start
- address is not meaningful for this object file format, we use it
- instead to indicate the number of zeroes to skip at the start of
- the file. objcopy cooperates by specially setting the start
- address to zero by default. */
- #include "sysdep.h"
- #include "bfd.h"
- #include "safe-ctype.h"
- #include "libbfd.h"
- /* Any bfd we create by reading a binary file has three symbols:
- a start symbol, an end symbol, and an absolute length symbol. */
- #define BIN_SYMS 3
- /* Create a binary object. Invoked via bfd_set_format. */
- static bool
- binary_mkobject (bfd *abfd ATTRIBUTE_UNUSED)
- {
- return true;
- }
- /* Any file may be considered to be a binary file, provided the target
- was not defaulted. That is, it must be explicitly specified as
- being binary. */
- static bfd_cleanup
- binary_object_p (bfd *abfd)
- {
- struct stat statbuf;
- asection *sec;
- flagword flags;
- if (abfd->target_defaulted)
- {
- bfd_set_error (bfd_error_wrong_format);
- return NULL;
- }
- abfd->symcount = BIN_SYMS;
- /* Find the file size. */
- if (bfd_stat (abfd, &statbuf) < 0)
- {
- bfd_set_error (bfd_error_system_call);
- return NULL;
- }
- /* One data section. */
- flags = SEC_ALLOC | SEC_LOAD | SEC_DATA | SEC_HAS_CONTENTS;
- sec = bfd_make_section_with_flags (abfd, ".data", flags);
- if (sec == NULL)
- return NULL;
- sec->vma = 0;
- sec->size = statbuf.st_size;
- sec->filepos = 0;
- abfd->tdata.any = (void *) sec;
- return _bfd_no_cleanup;
- }
- #define binary_close_and_cleanup _bfd_generic_close_and_cleanup
- #define binary_bfd_free_cached_info _bfd_generic_bfd_free_cached_info
- #define binary_new_section_hook _bfd_generic_new_section_hook
- /* Get contents of the only section. */
- static bool
- binary_get_section_contents (bfd *abfd,
- asection *section,
- void * location,
- file_ptr offset,
- bfd_size_type count)
- {
- if (bfd_seek (abfd, section->filepos + offset, SEEK_SET) != 0
- || bfd_bread (location, count, abfd) != count)
- return false;
- return true;
- }
- /* Return the amount of memory needed to read the symbol table. */
- static long
- binary_get_symtab_upper_bound (bfd *abfd ATTRIBUTE_UNUSED)
- {
- return (BIN_SYMS + 1) * sizeof (asymbol *);
- }
- /* Create a symbol name based on the bfd's filename. */
- static char *
- mangle_name (bfd *abfd, char *suffix)
- {
- bfd_size_type size;
- char *buf;
- char *p;
- size = (strlen (bfd_get_filename (abfd))
- + strlen (suffix)
- + sizeof "_binary__");
- buf = (char *) bfd_alloc (abfd, size);
- if (buf == NULL)
- return "";
- sprintf (buf, "_binary_%s_%s", bfd_get_filename (abfd), suffix);
- /* Change any non-alphanumeric characters to underscores. */
- for (p = buf; *p; p++)
- if (! ISALNUM (*p))
- *p = '_';
- return buf;
- }
- /* Return the symbol table. */
- static long
- binary_canonicalize_symtab (bfd *abfd, asymbol **alocation)
- {
- asection *sec = (asection *) abfd->tdata.any;
- asymbol *syms;
- unsigned int i;
- size_t amt = BIN_SYMS * sizeof (asymbol);
- syms = (asymbol *) bfd_alloc (abfd, amt);
- if (syms == NULL)
- return -1;
- /* Start symbol. */
- syms[0].the_bfd = abfd;
- syms[0].name = mangle_name (abfd, "start");
- syms[0].value = 0;
- syms[0].flags = BSF_GLOBAL;
- syms[0].section = sec;
- syms[0].udata.p = NULL;
- /* End symbol. */
- syms[1].the_bfd = abfd;
- syms[1].name = mangle_name (abfd, "end");
- syms[1].value = sec->size;
- syms[1].flags = BSF_GLOBAL;
- syms[1].section = sec;
- syms[1].udata.p = NULL;
- /* Size symbol. */
- syms[2].the_bfd = abfd;
- syms[2].name = mangle_name (abfd, "size");
- syms[2].value = sec->size;
- syms[2].flags = BSF_GLOBAL;
- syms[2].section = bfd_abs_section_ptr;
- syms[2].udata.p = NULL;
- for (i = 0; i < BIN_SYMS; i++)
- *alocation++ = syms++;
- *alocation = NULL;
- return BIN_SYMS;
- }
- #define binary_make_empty_symbol _bfd_generic_make_empty_symbol
- #define binary_print_symbol _bfd_nosymbols_print_symbol
- #define binary_get_symbol_version_string \
- _bfd_nosymbols_get_symbol_version_string
- /* Get information about a symbol. */
- static void
- binary_get_symbol_info (bfd *ignore_abfd ATTRIBUTE_UNUSED,
- asymbol *symbol,
- symbol_info *ret)
- {
- bfd_symbol_info (symbol, ret);
- }
- #define binary_bfd_is_local_label_name bfd_generic_is_local_label_name
- #define binary_get_lineno _bfd_nosymbols_get_lineno
- #define binary_find_nearest_line _bfd_nosymbols_find_nearest_line
- #define binary_find_line _bfd_nosymbols_find_line
- #define binary_find_inliner_info _bfd_nosymbols_find_inliner_info
- #define binary_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol
- #define binary_read_minisymbols _bfd_generic_read_minisymbols
- #define binary_minisymbol_to_symbol _bfd_generic_minisymbol_to_symbol
- #define binary_bfd_is_target_special_symbol _bfd_bool_bfd_asymbol_false
- /* Set the architecture of a binary file. */
- #define binary_set_arch_mach _bfd_generic_set_arch_mach
- /* Write section contents of a binary file. */
- static bool
- binary_set_section_contents (bfd *abfd,
- asection *sec,
- const void * data,
- file_ptr offset,
- bfd_size_type size)
- {
- if (size == 0)
- return true;
- if (! abfd->output_has_begun)
- {
- bool found_low;
- bfd_vma low;
- asection *s;
- /* The lowest section LMA sets the virtual address of the start
- of the file. We use this to set the file position of all the
- sections. */
- found_low = false;
- low = 0;
- for (s = abfd->sections; s != NULL; s = s->next)
- if (((s->flags
- & (SEC_HAS_CONTENTS | SEC_LOAD | SEC_ALLOC | SEC_NEVER_LOAD))
- == (SEC_HAS_CONTENTS | SEC_LOAD | SEC_ALLOC))
- && (s->size > 0)
- && (! found_low || s->lma < low))
- {
- low = s->lma;
- found_low = true;
- }
- for (s = abfd->sections; s != NULL; s = s->next)
- {
- unsigned int opb = bfd_octets_per_byte (abfd, s);
- s->filepos = (s->lma - low) * opb;
- /* Skip following warning check for sections that will not
- occupy file space. */
- if ((s->flags
- & (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_NEVER_LOAD))
- != (SEC_HAS_CONTENTS | SEC_ALLOC)
- || (s->size == 0))
- continue;
- /* If attempting to generate a binary file from a bfd with
- LMA's all over the place, huge (sparse?) binary files may
- result. This condition attempts to detect this situation
- and print a warning. Better heuristics would be nice to
- have. */
- if (s->filepos < 0)
- _bfd_error_handler
- /* xgettext:c-format */
- (_("warning: writing section `%pA' at huge (ie negative) "
- "file offset"),
- s);
- }
- abfd->output_has_begun = true;
- }
- /* We don't want to output anything for a section that is neither
- loaded nor allocated. The contents of such a section are not
- meaningful in the binary format. */
- if ((sec->flags & (SEC_LOAD | SEC_ALLOC)) == 0)
- return true;
- if ((sec->flags & SEC_NEVER_LOAD) != 0)
- return true;
- return _bfd_generic_set_section_contents (abfd, sec, data, offset, size);
- }
- /* No space is required for header information. */
- static int
- binary_sizeof_headers (bfd *abfd ATTRIBUTE_UNUSED,
- struct bfd_link_info *info ATTRIBUTE_UNUSED)
- {
- return 0;
- }
- #define binary_bfd_get_relocated_section_contents bfd_generic_get_relocated_section_contents
- #define binary_bfd_relax_section bfd_generic_relax_section
- #define binary_bfd_gc_sections bfd_generic_gc_sections
- #define binary_bfd_lookup_section_flags bfd_generic_lookup_section_flags
- #define binary_bfd_merge_sections bfd_generic_merge_sections
- #define binary_bfd_is_group_section bfd_generic_is_group_section
- #define binary_bfd_group_name bfd_generic_group_name
- #define binary_bfd_discard_group bfd_generic_discard_group
- #define binary_section_already_linked _bfd_generic_section_already_linked
- #define binary_bfd_define_common_symbol bfd_generic_define_common_symbol
- #define binary_bfd_link_hide_symbol _bfd_generic_link_hide_symbol
- #define binary_bfd_define_start_stop bfd_generic_define_start_stop
- #define binary_bfd_link_hash_table_create _bfd_generic_link_hash_table_create
- #define binary_bfd_link_just_syms _bfd_generic_link_just_syms
- #define binary_bfd_copy_link_hash_symbol_type _bfd_generic_copy_link_hash_symbol_type
- #define binary_bfd_link_add_symbols _bfd_generic_link_add_symbols
- #define binary_bfd_final_link _bfd_generic_final_link
- #define binary_bfd_link_split_section _bfd_generic_link_split_section
- #define binary_get_section_contents_in_window _bfd_generic_get_section_contents_in_window
- #define binary_bfd_link_check_relocs _bfd_generic_link_check_relocs
- const bfd_target binary_vec =
- {
- "binary", /* name */
- bfd_target_unknown_flavour, /* flavour */
- BFD_ENDIAN_UNKNOWN, /* byteorder */
- BFD_ENDIAN_UNKNOWN, /* header_byteorder */
- EXEC_P, /* object_flags */
- (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE | SEC_DATA
- | SEC_ROM | SEC_HAS_CONTENTS), /* section_flags */
- 0, /* symbol_leading_char */
- ' ', /* ar_pad_char */
- 16, /* ar_max_namelen */
- 255, /* match priority. */
- TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols. */
- bfd_getb64, bfd_getb_signed_64, bfd_putb64,
- bfd_getb32, bfd_getb_signed_32, bfd_putb32,
- bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */
- bfd_getb64, bfd_getb_signed_64, bfd_putb64,
- bfd_getb32, bfd_getb_signed_32, bfd_putb32,
- bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */
- { /* bfd_check_format */
- _bfd_dummy_target,
- binary_object_p,
- _bfd_dummy_target,
- _bfd_dummy_target,
- },
- { /* bfd_set_format */
- _bfd_bool_bfd_false_error,
- binary_mkobject,
- _bfd_bool_bfd_false_error,
- _bfd_bool_bfd_false_error,
- },
- { /* bfd_write_contents */
- _bfd_bool_bfd_false_error,
- _bfd_bool_bfd_true,
- _bfd_bool_bfd_false_error,
- _bfd_bool_bfd_false_error,
- },
- BFD_JUMP_TABLE_GENERIC (binary),
- BFD_JUMP_TABLE_COPY (_bfd_generic),
- BFD_JUMP_TABLE_CORE (_bfd_nocore),
- BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
- BFD_JUMP_TABLE_SYMBOLS (binary),
- BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
- BFD_JUMP_TABLE_WRITE (binary),
- BFD_JUMP_TABLE_LINK (binary),
- BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
- NULL,
- NULL
- };
|