1 /* BFD back-end for binary objects. 2 Copyright 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 3 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 44 static bfd_boolean binary_mkobject PARAMS ((bfd *)); 45 static const bfd_target *binary_object_p PARAMS ((bfd *)); 46 static bfd_boolean binary_get_section_contents 47 PARAMS ((bfd *, asection *, PTR, file_ptr, bfd_size_type)); 48 static long binary_get_symtab_upper_bound PARAMS ((bfd *)); 49 static char *mangle_name PARAMS ((bfd *, char *)); 50 static long binary_canonicalize_symtab PARAMS ((bfd *, asymbol **)); 51 static void binary_get_symbol_info PARAMS ((bfd *, asymbol *, symbol_info *)); 52 static bfd_boolean binary_set_section_contents 53 PARAMS ((bfd *, asection *, const PTR, file_ptr, bfd_size_type)); 54 static 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. */ 58 enum bfd_architecture bfd_external_binary_architecture = bfd_arch_unknown; 59 unsigned long bfd_external_machine = 0; 60 61 /* Create a binary object. Invoked via bfd_set_format. */ 62 63 static bfd_boolean 64 binary_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 74 static const bfd_target * 75 binary_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->_raw_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. */ 123 124 static bfd_boolean 125 binary_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. */ 139 140 static long 141 binary_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. */ 148 149 static char * 150 mangle_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. */ 177 178 static long 179 binary_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->_raw_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->_raw_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. */ 227 228 static void 229 binary_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_local_label_name bfd_generic_is_local_label_name 238 #define binary_get_lineno _bfd_nosymbols_get_lineno 239 #define binary_find_nearest_line _bfd_nosymbols_find_nearest_line 240 #define binary_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol 241 #define binary_read_minisymbols _bfd_generic_read_minisymbols 242 #define binary_minisymbol_to_symbol _bfd_generic_minisymbol_to_symbol 243 244 #define binary_get_reloc_upper_bound \ 245 ((long (*) PARAMS ((bfd *, asection *))) bfd_0l) 246 #define binary_canonicalize_reloc \ 247 ((long (*) PARAMS ((bfd *, asection *, arelent **, asymbol **))) bfd_0l) 248 #define binary_bfd_reloc_type_lookup _bfd_norelocs_bfd_reloc_type_lookup 249 250 /* Set the architecture of a binary file. */ 251 #define binary_set_arch_mach _bfd_generic_set_arch_mach 252 253 /* Write section contents of a binary file. */ 254 255 static bfd_boolean 256 binary_set_section_contents (abfd, sec, data, offset, size) 257 bfd *abfd; 258 asection *sec; 259 const PTR data; 260 file_ptr offset; 261 bfd_size_type size; 262 { 263 if (size == 0) 264 return TRUE; 265 266 if (! abfd->output_has_begun) 267 { 268 bfd_boolean found_low; 269 bfd_vma low; 270 asection *s; 271 272 /* The lowest section LMA sets the virtual address of the start 273 of the file. We use this to set the file position of all the 274 sections. */ 275 found_low = FALSE; 276 low = 0; 277 for (s = abfd->sections; s != NULL; s = s->next) 278 if (((s->flags 279 & (SEC_HAS_CONTENTS | SEC_LOAD | SEC_ALLOC | SEC_NEVER_LOAD)) 280 == (SEC_HAS_CONTENTS | SEC_LOAD | SEC_ALLOC)) 281 && (s->_raw_size > 0) 282 && (! found_low || s->lma < low)) 283 { 284 low = s->lma; 285 found_low = TRUE; 286 } 287 288 for (s = abfd->sections; s != NULL; s = s->next) 289 { 290 s->filepos = s->lma - low; 291 292 /* Skip following warning check for sections that will not 293 occupy file space. */ 294 if ((s->flags 295 & (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_NEVER_LOAD)) 296 != (SEC_HAS_CONTENTS | SEC_ALLOC) 297 || (s->_raw_size == 0)) 298 continue; 299 300 /* If attempting to generate a binary file from a bfd with 301 LMA's all over the place, huge (sparse?) binary files may 302 result. This condition attempts to detect this situation 303 and print a warning. Better heuristics would be nice to 304 have. */ 305 306 if (s->filepos < 0) 307 (*_bfd_error_handler) 308 (_("Warning: Writing section `%s' to huge (ie negative) file offset 0x%lx."), 309 bfd_get_section_name (abfd, s), 310 (unsigned long) s->filepos); 311 } 312 313 abfd->output_has_begun = TRUE; 314 } 315 316 /* We don't want to output anything for a section that is neither 317 loaded nor allocated. The contents of such a section are not 318 meaningful in the binary format. */ 319 if ((sec->flags & (SEC_LOAD | SEC_ALLOC)) == 0) 320 return TRUE; 321 if ((sec->flags & SEC_NEVER_LOAD) != 0) 322 return TRUE; 323 324 return _bfd_generic_set_section_contents (abfd, sec, data, offset, size); 325 } 326 327 /* No space is required for header information. */ 328 329 static int 330 binary_sizeof_headers (abfd, exec) 331 bfd *abfd ATTRIBUTE_UNUSED; 332 bfd_boolean exec ATTRIBUTE_UNUSED; 333 { 334 return 0; 335 } 336 337 #define binary_bfd_get_relocated_section_contents \ 338 bfd_generic_get_relocated_section_contents 339 #define binary_bfd_relax_section bfd_generic_relax_section 340 #define binary_bfd_gc_sections bfd_generic_gc_sections 341 #define binary_bfd_merge_sections bfd_generic_merge_sections 342 #define binary_bfd_discard_group bfd_generic_discard_group 343 #define binary_bfd_link_hash_table_create _bfd_generic_link_hash_table_create 344 #define binary_bfd_link_hash_table_free _bfd_generic_link_hash_table_free 345 #define binary_bfd_link_just_syms _bfd_generic_link_just_syms 346 #define binary_bfd_link_add_symbols _bfd_generic_link_add_symbols 347 #define binary_bfd_final_link _bfd_generic_final_link 348 #define binary_bfd_link_split_section _bfd_generic_link_split_section 349 #define binary_get_section_contents_in_window \ 350 _bfd_generic_get_section_contents_in_window 351 352 const bfd_target binary_vec = 353 { 354 "binary", /* name */ 355 bfd_target_unknown_flavour, /* flavour */ 356 BFD_ENDIAN_UNKNOWN, /* byteorder */ 357 BFD_ENDIAN_UNKNOWN, /* header_byteorder */ 358 EXEC_P, /* object_flags */ 359 (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE | SEC_DATA 360 | SEC_ROM | SEC_HAS_CONTENTS), /* section_flags */ 361 0, /* symbol_leading_char */ 362 ' ', /* ar_pad_char */ 363 16, /* ar_max_namelen */ 364 bfd_getb64, bfd_getb_signed_64, bfd_putb64, 365 bfd_getb32, bfd_getb_signed_32, bfd_putb32, 366 bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */ 367 bfd_getb64, bfd_getb_signed_64, bfd_putb64, 368 bfd_getb32, bfd_getb_signed_32, bfd_putb32, 369 bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */ 370 { /* bfd_check_format */ 371 _bfd_dummy_target, 372 binary_object_p, /* bfd_check_format */ 373 _bfd_dummy_target, 374 _bfd_dummy_target, 375 }, 376 { /* bfd_set_format */ 377 bfd_false, 378 binary_mkobject, 379 bfd_false, 380 bfd_false, 381 }, 382 { /* bfd_write_contents */ 383 bfd_false, 384 bfd_true, 385 bfd_false, 386 bfd_false, 387 }, 388 389 BFD_JUMP_TABLE_GENERIC (binary), 390 BFD_JUMP_TABLE_COPY (_bfd_generic), 391 BFD_JUMP_TABLE_CORE (_bfd_nocore), 392 BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive), 393 BFD_JUMP_TABLE_SYMBOLS (binary), 394 BFD_JUMP_TABLE_RELOCS (binary), 395 BFD_JUMP_TABLE_WRITE (binary), 396 BFD_JUMP_TABLE_LINK (binary), 397 BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic), 398 399 NULL, 400 401 NULL 402 }; 403