1/* BFD back-end for binary objects. 2 Copyright 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 3 2004 Free Software Foundation, Inc. 4 Written by Ian Lance Taylor, Cygnus Support, <ian@cygnus.com> 5 6 This file is part of BFD, the Binary File Descriptor library. 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 2 of the License, or 11 (at your option) any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; if not, write to the Free Software 20 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ 21 22/* This is a BFD backend which may be used to write binary objects. 23 It may only be used for output, not input. The intention is that 24 this may be used as an output format for objcopy in order to 25 generate raw binary data. 26 27 This is very simple. The only complication is that the real data 28 will start at some address X, and in some cases we will not want to 29 include X zeroes just to get to that point. Since the start 30 address is not meaningful for this object file format, we use it 31 instead to indicate the number of zeroes to skip at the start of 32 the file. objcopy cooperates by specially setting the start 33 address to zero by default. */ 34 35#include "bfd.h" 36#include "sysdep.h" 37#include "safe-ctype.h" 38#include "libbfd.h" 39 40/* Any bfd we create by reading a binary file has three symbols: 41 a start symbol, an end symbol, and an absolute length symbol. */ 42#define BIN_SYMS 3 43 44static bfd_boolean binary_mkobject PARAMS ((bfd *)); 45static const bfd_target *binary_object_p PARAMS ((bfd *)); 46static bfd_boolean binary_get_section_contents 47 PARAMS ((bfd *, asection *, PTR, file_ptr, bfd_size_type)); 48static long binary_get_symtab_upper_bound PARAMS ((bfd *)); 49static char *mangle_name PARAMS ((bfd *, char *)); 50static long binary_canonicalize_symtab PARAMS ((bfd *, asymbol **)); 51static void binary_get_symbol_info PARAMS ((bfd *, asymbol *, symbol_info *)); 52static bfd_boolean binary_set_section_contents 53 PARAMS ((bfd *, asection *, const PTR, file_ptr, bfd_size_type)); 54static int binary_sizeof_headers PARAMS ((bfd *, bfd_boolean)); 55 56/* Set by external programs - specifies the BFD architecture and 57 machine number to be uses when creating binary BFDs. */ 58enum bfd_architecture bfd_external_binary_architecture = bfd_arch_unknown; 59unsigned long bfd_external_machine = 0; 60 61/* Create a binary object. Invoked via bfd_set_format. */ 62 63static bfd_boolean 64binary_mkobject (abfd) 65 bfd *abfd ATTRIBUTE_UNUSED; 66{ 67 return TRUE; 68} 69 70/* Any file may be considered to be a binary file, provided the target 71 was not defaulted. That is, it must be explicitly specified as 72 being binary. */ 73 74static const bfd_target * 75binary_object_p (abfd) 76 bfd *abfd; 77{ 78 struct stat statbuf; 79 asection *sec; 80 81 if (abfd->target_defaulted) 82 { 83 bfd_set_error (bfd_error_wrong_format); 84 return NULL; 85 } 86 87 abfd->symcount = BIN_SYMS; 88 89 /* Find the file size. */ 90 if (bfd_stat (abfd, &statbuf) < 0) 91 { 92 bfd_set_error (bfd_error_system_call); 93 return NULL; 94 } 95 96 /* One data section. */ 97 sec = bfd_make_section (abfd, ".data"); 98 if (sec == NULL) 99 return NULL; 100 sec->flags = SEC_ALLOC | SEC_LOAD | SEC_DATA | SEC_HAS_CONTENTS; 101 sec->vma = 0; 102 sec->size = statbuf.st_size; 103 sec->filepos = 0; 104 105 abfd->tdata.any = (PTR) sec; 106 107 if (bfd_get_arch_info (abfd) != NULL) 108 { 109 if ((bfd_get_arch_info (abfd)->arch == bfd_arch_unknown) 110 && (bfd_external_binary_architecture != bfd_arch_unknown)) 111 bfd_set_arch_info (abfd, bfd_lookup_arch 112 (bfd_external_binary_architecture, bfd_external_machine)); 113 } 114 115 return abfd->xvec; 116} 117 118#define binary_close_and_cleanup _bfd_generic_close_and_cleanup 119#define binary_bfd_free_cached_info _bfd_generic_bfd_free_cached_info 120#define binary_new_section_hook _bfd_generic_new_section_hook 121 122/* Get contents of the only section. */ 123 124static bfd_boolean 125binary_get_section_contents (abfd, section, location, offset, count) 126 bfd *abfd; 127 asection *section ATTRIBUTE_UNUSED; 128 PTR location; 129 file_ptr offset; 130 bfd_size_type count; 131{ 132 if (bfd_seek (abfd, offset, SEEK_SET) != 0 133 || bfd_bread (location, count, abfd) != count) 134 return FALSE; 135 return TRUE; 136} 137 138/* Return the amount of memory needed to read the symbol table. */ 139 140static long 141binary_get_symtab_upper_bound (abfd) 142 bfd *abfd ATTRIBUTE_UNUSED; 143{ 144 return (BIN_SYMS + 1) * sizeof (asymbol *); 145} 146 147/* Create a symbol name based on the bfd's filename. */ 148 149static char * 150mangle_name (abfd, suffix) 151 bfd *abfd; 152 char *suffix; 153{ 154 bfd_size_type size; 155 char *buf; 156 char *p; 157 158 size = (strlen (bfd_get_filename (abfd)) 159 + strlen (suffix) 160 + sizeof "_binary__"); 161 162 buf = (char *) bfd_alloc (abfd, size); 163 if (buf == NULL) 164 return ""; 165 166 sprintf (buf, "_binary_%s_%s", bfd_get_filename (abfd), suffix); 167 168 /* Change any non-alphanumeric characters to underscores. */ 169 for (p = buf; *p; p++) 170 if (! ISALNUM (*p)) 171 *p = '_'; 172 173 return buf; 174} 175 176/* Return the symbol table. */ 177 178static long 179binary_canonicalize_symtab (abfd, alocation) 180 bfd *abfd; 181 asymbol **alocation; 182{ 183 asection *sec = (asection *) abfd->tdata.any; 184 asymbol *syms; 185 unsigned int i; 186 bfd_size_type amt = BIN_SYMS * sizeof (asymbol); 187 188 syms = (asymbol *) bfd_alloc (abfd, amt); 189 if (syms == NULL) 190 return 0; 191 192 /* Start symbol. */ 193 syms[0].the_bfd = abfd; 194 syms[0].name = mangle_name (abfd, "start"); 195 syms[0].value = 0; 196 syms[0].flags = BSF_GLOBAL; 197 syms[0].section = sec; 198 syms[0].udata.p = NULL; 199 200 /* End symbol. */ 201 syms[1].the_bfd = abfd; 202 syms[1].name = mangle_name (abfd, "end"); 203 syms[1].value = sec->size; 204 syms[1].flags = BSF_GLOBAL; 205 syms[1].section = sec; 206 syms[1].udata.p = NULL; 207 208 /* Size symbol. */ 209 syms[2].the_bfd = abfd; 210 syms[2].name = mangle_name (abfd, "size"); 211 syms[2].value = sec->size; 212 syms[2].flags = BSF_GLOBAL; 213 syms[2].section = bfd_abs_section_ptr; 214 syms[2].udata.p = NULL; 215 216 for (i = 0; i < BIN_SYMS; i++) 217 *alocation++ = syms++; 218 *alocation = NULL; 219 220 return BIN_SYMS; 221} 222 223#define binary_make_empty_symbol _bfd_generic_make_empty_symbol 224#define binary_print_symbol _bfd_nosymbols_print_symbol 225 226/* Get information about a symbol. */ 227 228static void 229binary_get_symbol_info (ignore_abfd, symbol, ret) 230 bfd *ignore_abfd ATTRIBUTE_UNUSED; 231 asymbol *symbol; 232 symbol_info *ret; 233{ 234 bfd_symbol_info (symbol, ret); 235} 236 237#define binary_bfd_is_target_special_symbol ((bfd_boolean (*) (bfd *, asymbol *)) bfd_false) 238#define binary_bfd_is_local_label_name bfd_generic_is_local_label_name 239#define binary_get_lineno _bfd_nosymbols_get_lineno 240#define binary_find_nearest_line _bfd_nosymbols_find_nearest_line 241#define binary_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol 242#define binary_read_minisymbols _bfd_generic_read_minisymbols 243#define binary_minisymbol_to_symbol _bfd_generic_minisymbol_to_symbol 244 245#define binary_get_reloc_upper_bound \ 246 ((long (*) PARAMS ((bfd *, asection *))) bfd_0l) 247#define binary_canonicalize_reloc \ 248 ((long (*) PARAMS ((bfd *, asection *, arelent **, asymbol **))) bfd_0l) 249#define binary_bfd_reloc_type_lookup _bfd_norelocs_bfd_reloc_type_lookup 250 251/* Set the architecture of a binary file. */ 252#define binary_set_arch_mach _bfd_generic_set_arch_mach 253 254/* Write section contents of a binary file. */ 255 256static bfd_boolean 257binary_set_section_contents (abfd, sec, data, offset, size) 258 bfd *abfd; 259 asection *sec; 260 const PTR data; 261 file_ptr offset; 262 bfd_size_type size; 263{ 264 if (size == 0) 265 return TRUE; 266 267 if (! abfd->output_has_begun) 268 { 269 bfd_boolean found_low; 270 bfd_vma low; 271 asection *s; 272 273 /* The lowest section LMA sets the virtual address of the start 274 of the file. We use this to set the file position of all the 275 sections. */ 276 found_low = FALSE; 277 low = 0; 278 for (s = abfd->sections; s != NULL; s = s->next) 279 if (((s->flags 280 & (SEC_HAS_CONTENTS | SEC_LOAD | SEC_ALLOC | SEC_NEVER_LOAD)) 281 == (SEC_HAS_CONTENTS | SEC_LOAD | SEC_ALLOC)) 282 && (s->size > 0) 283 && (! found_low || s->lma < low)) 284 { 285 low = s->lma; 286 found_low = TRUE; 287 } 288 289 for (s = abfd->sections; s != NULL; s = s->next) 290 { 291 s->filepos = s->lma - low; 292 293 /* Skip following warning check for sections that will not 294 occupy file space. */ 295 if ((s->flags 296 & (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_NEVER_LOAD)) 297 != (SEC_HAS_CONTENTS | SEC_ALLOC) 298 || (s->size == 0)) 299 continue; 300 301 /* If attempting to generate a binary file from a bfd with 302 LMA's all over the place, huge (sparse?) binary files may 303 result. This condition attempts to detect this situation 304 and print a warning. Better heuristics would be nice to 305 have. */ 306 307 if (s->filepos < 0) 308 (*_bfd_error_handler) 309 (_("Warning: Writing section `%s' to huge (ie negative) file offset 0x%lx."), 310 bfd_get_section_name (abfd, s), 311 (unsigned long) s->filepos); 312 } 313 314 abfd->output_has_begun = TRUE; 315 } 316 317 /* We don't want to output anything for a section that is neither 318 loaded nor allocated. The contents of such a section are not 319 meaningful in the binary format. */ 320 if ((sec->flags & (SEC_LOAD | SEC_ALLOC)) == 0) 321 return TRUE; 322 if ((sec->flags & SEC_NEVER_LOAD) != 0) 323 return TRUE; 324 325 return _bfd_generic_set_section_contents (abfd, sec, data, offset, size); 326} 327 328/* No space is required for header information. */ 329 330static int 331binary_sizeof_headers (abfd, exec) 332 bfd *abfd ATTRIBUTE_UNUSED; 333 bfd_boolean exec ATTRIBUTE_UNUSED; 334{ 335 return 0; 336} 337 338#define binary_bfd_get_relocated_section_contents \ 339 bfd_generic_get_relocated_section_contents 340#define binary_bfd_relax_section bfd_generic_relax_section 341#define binary_bfd_gc_sections bfd_generic_gc_sections 342#define binary_bfd_merge_sections bfd_generic_merge_sections 343#define binary_bfd_is_group_section bfd_generic_is_group_section 344#define binary_bfd_discard_group bfd_generic_discard_group 345#define binary_section_already_linked \ 346 _bfd_generic_section_already_linked 347#define binary_bfd_link_hash_table_create _bfd_generic_link_hash_table_create 348#define binary_bfd_link_hash_table_free _bfd_generic_link_hash_table_free 349#define binary_bfd_link_just_syms _bfd_generic_link_just_syms 350#define binary_bfd_link_add_symbols _bfd_generic_link_add_symbols 351#define binary_bfd_final_link _bfd_generic_final_link 352#define binary_bfd_link_split_section _bfd_generic_link_split_section 353#define binary_get_section_contents_in_window \ 354 _bfd_generic_get_section_contents_in_window 355 356const bfd_target binary_vec = 357{ 358 "binary", /* name */ 359 bfd_target_unknown_flavour, /* flavour */ 360 BFD_ENDIAN_UNKNOWN, /* byteorder */ 361 BFD_ENDIAN_UNKNOWN, /* header_byteorder */ 362 EXEC_P, /* object_flags */ 363 (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE | SEC_DATA 364 | SEC_ROM | SEC_HAS_CONTENTS), /* section_flags */ 365 0, /* symbol_leading_char */ 366 ' ', /* ar_pad_char */ 367 16, /* ar_max_namelen */ 368 bfd_getb64, bfd_getb_signed_64, bfd_putb64, 369 bfd_getb32, bfd_getb_signed_32, bfd_putb32, 370 bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */ 371 bfd_getb64, bfd_getb_signed_64, bfd_putb64, 372 bfd_getb32, bfd_getb_signed_32, bfd_putb32, 373 bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */ 374 { /* bfd_check_format */ 375 _bfd_dummy_target, 376 binary_object_p, /* bfd_check_format */ 377 _bfd_dummy_target, 378 _bfd_dummy_target, 379 }, 380 { /* bfd_set_format */ 381 bfd_false, 382 binary_mkobject, 383 bfd_false, 384 bfd_false, 385 }, 386 { /* bfd_write_contents */ 387 bfd_false, 388 bfd_true, 389 bfd_false, 390 bfd_false, 391 }, 392 393 BFD_JUMP_TABLE_GENERIC (binary), 394 BFD_JUMP_TABLE_COPY (_bfd_generic), 395 BFD_JUMP_TABLE_CORE (_bfd_nocore), 396 BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive), 397 BFD_JUMP_TABLE_SYMBOLS (binary), 398 BFD_JUMP_TABLE_RELOCS (binary), 399 BFD_JUMP_TABLE_WRITE (binary), 400 BFD_JUMP_TABLE_LINK (binary), 401 BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic), 402 403 NULL, 404 405 NULL 406}; 407