1 /* BFD back-end for binary objects. 2 Copyright 1994, 95, 96, 97, 1998 Free Software Foundation, Inc. 3 Written by Ian Lance Taylor, Cygnus Support, <[email protected]> 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 9 the Free Software Foundation; either version 2 of the License, or 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 19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ 20 21 /* This is a BFD backend which may be used to write binary objects. 22 It may only be used for output, not input. The intention is that 23 this may be used as an output format for objcopy in order to 24 generate raw binary data. 25 26 This is very simple. The only complication is that the real data 27 will start at some address X, and in some cases we will not want to 28 include X zeroes just to get to that point. Since the start 29 address is not meaningful for this object file format, we use it 30 instead to indicate the number of zeroes to skip at the start of 31 the file. objcopy cooperates by specially setting the start 32 address to zero by default. */ 33 34 #include <ctype.h> 35 36 #include "bfd.h" 37 #include "sysdep.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 boolean binary_mkobject PARAMS ((bfd *)); 45 static const bfd_target *binary_object_p PARAMS ((bfd *)); 46 static 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_get_symtab PARAMS ((bfd *, asymbol **)); 51 static asymbol *binary_make_empty_symbol PARAMS ((bfd *)); 52 static void binary_get_symbol_info PARAMS ((bfd *, asymbol *, symbol_info *)); 53 static boolean binary_set_section_contents 54 PARAMS ((bfd *, asection *, PTR, file_ptr, bfd_size_type)); 55 static int binary_sizeof_headers PARAMS ((bfd *, boolean)); 56 57 /* Create a binary object. Invoked via bfd_set_format. */ 58 59 static boolean 60 binary_mkobject (abfd) 61 bfd *abfd; 62 { 63 return true; 64 } 65 66 /* Any file may be considered to be a binary file, provided the target 67 was not defaulted. That is, it must be explicitly specified as 68 being binary. */ 69 70 static const bfd_target * 71 binary_object_p (abfd) 72 bfd *abfd; 73 { 74 struct stat statbuf; 75 asection *sec; 76 77 if (abfd->target_defaulted) 78 { 79 bfd_set_error (bfd_error_wrong_format); 80 return NULL; 81 } 82 83 abfd->symcount = BIN_SYMS; 84 85 /* Find the file size. */ 86 if (bfd_stat (abfd, &statbuf) < 0) 87 { 88 bfd_set_error (bfd_error_system_call); 89 return NULL; 90 } 91 92 /* One data section. */ 93 sec = bfd_make_section (abfd, ".data"); 94 if (sec == NULL) 95 return NULL; 96 sec->flags = SEC_ALLOC | SEC_LOAD | SEC_DATA | SEC_HAS_CONTENTS; 97 sec->vma = 0; 98 sec->_raw_size = statbuf.st_size; 99 sec->filepos = 0; 100 101 abfd->tdata.any = (PTR) sec; 102 103 return abfd->xvec; 104 } 105 106 #define binary_close_and_cleanup _bfd_generic_close_and_cleanup 107 #define binary_bfd_free_cached_info _bfd_generic_bfd_free_cached_info 108 #define binary_new_section_hook _bfd_generic_new_section_hook 109 110 /* Get contents of the only section. */ 111 112 static boolean 113 binary_get_section_contents (abfd, section, location, offset, count) 114 bfd *abfd; 115 asection *section; 116 PTR location; 117 file_ptr offset; 118 bfd_size_type count; 119 { 120 if (bfd_seek (abfd, offset, SEEK_SET) != 0 121 || bfd_read (location, 1, count, abfd) != count) 122 return false; 123 return true; 124 } 125 126 /* Return the amount of memory needed to read the symbol table. */ 127 128 static long 129 binary_get_symtab_upper_bound (abfd) 130 bfd *abfd; 131 { 132 return (BIN_SYMS + 1) * sizeof (asymbol *); 133 } 134 135 /* Create a symbol name based on the bfd's filename. */ 136 137 static char * 138 mangle_name (abfd, suffix) 139 bfd *abfd; 140 char *suffix; 141 { 142 int size; 143 char *buf; 144 char *p; 145 146 size = (strlen (bfd_get_filename (abfd)) 147 + strlen (suffix) 148 + sizeof "_binary__"); 149 150 buf = (char *) bfd_alloc (abfd, size); 151 if (buf == NULL) 152 return ""; 153 154 sprintf (buf, "_binary_%s_%s", bfd_get_filename (abfd), suffix); 155 156 /* Change any non-alphanumeric characters to underscores. */ 157 for (p = buf; *p; p++) 158 if (! isalnum ((unsigned char) *p)) 159 *p = '_'; 160 161 return buf; 162 } 163 164 /* Return the symbol table. */ 165 166 static long 167 binary_get_symtab (abfd, alocation) 168 bfd *abfd; 169 asymbol **alocation; 170 { 171 asection *sec = (asection *) abfd->tdata.any; 172 asymbol *syms; 173 unsigned int i; 174 175 syms = (asymbol *) bfd_alloc (abfd, BIN_SYMS * sizeof (asymbol)); 176 if (syms == NULL) 177 return false; 178 179 /* Start symbol. */ 180 syms[0].the_bfd = abfd; 181 syms[0].name = mangle_name (abfd, "start"); 182 syms[0].value = 0; 183 syms[0].flags = BSF_GLOBAL; 184 syms[0].section = sec; 185 syms[0].udata.p = NULL; 186 187 /* End symbol. */ 188 syms[1].the_bfd = abfd; 189 syms[1].name = mangle_name (abfd, "end"); 190 syms[1].value = sec->_raw_size; 191 syms[1].flags = BSF_GLOBAL; 192 syms[1].section = sec; 193 syms[1].udata.p = NULL; 194 195 /* Size symbol. */ 196 syms[2].the_bfd = abfd; 197 syms[2].name = mangle_name (abfd, "size"); 198 syms[2].value = sec->_raw_size; 199 syms[2].flags = BSF_GLOBAL; 200 syms[2].section = bfd_abs_section_ptr; 201 syms[2].udata.p = NULL; 202 203 for (i = 0; i < BIN_SYMS; i++) 204 *alocation++ = syms++; 205 *alocation = NULL; 206 207 return BIN_SYMS; 208 } 209 210 /* Make an empty symbol. */ 211 212 static asymbol * 213 binary_make_empty_symbol (abfd) 214 bfd *abfd; 215 { 216 return (asymbol *) bfd_alloc (abfd, sizeof (asymbol)); 217 } 218 219 #define binary_print_symbol _bfd_nosymbols_print_symbol 220 221 /* Get information about a symbol. */ 222 223 static void 224 binary_get_symbol_info (ignore_abfd, symbol, ret) 225 bfd *ignore_abfd; 226 asymbol *symbol; 227 symbol_info *ret; 228 { 229 bfd_symbol_info (symbol, ret); 230 } 231 232 #define binary_bfd_is_local_label_name bfd_generic_is_local_label_name 233 #define binary_get_lineno _bfd_nosymbols_get_lineno 234 #define binary_find_nearest_line _bfd_nosymbols_find_nearest_line 235 #define binary_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol 236 #define binary_read_minisymbols _bfd_generic_read_minisymbols 237 #define binary_minisymbol_to_symbol _bfd_generic_minisymbol_to_symbol 238 239 #define binary_get_reloc_upper_bound \ 240 ((long (*) PARAMS ((bfd *, asection *))) bfd_0l) 241 #define binary_canonicalize_reloc \ 242 ((long (*) PARAMS ((bfd *, asection *, arelent **, asymbol **))) bfd_0l) 243 #define binary_bfd_reloc_type_lookup _bfd_norelocs_bfd_reloc_type_lookup 244 245 /* Set the architecture of a binary file. */ 246 #define binary_set_arch_mach _bfd_generic_set_arch_mach 247 248 /* Write section contents of a binary file. */ 249 250 static boolean 251 binary_set_section_contents (abfd, sec, data, offset, size) 252 bfd *abfd; 253 asection *sec; 254 PTR data; 255 file_ptr offset; 256 bfd_size_type size; 257 { 258 /* We don't want to output anything for a section that is neither 259 loaded nor allocated. The contents of such a section are not 260 meaningful in the binary format. */ 261 if ((sec->flags & (SEC_LOAD | SEC_ALLOC)) == 0) 262 return true; 263 if ((sec->flags & SEC_NEVER_LOAD) != 0) 264 return true; 265 266 if (! abfd->output_has_begun) 267 { 268 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 & (SEC_HAS_CONTENTS | SEC_LOAD | SEC_ALLOC)) 279 == (SEC_HAS_CONTENTS | SEC_LOAD | SEC_ALLOC)) 280 && (! found_low || s->lma < low)) 281 { 282 low = s->lma; 283 found_low = true; 284 } 285 286 for (s = abfd->sections; s != NULL; s = s->next) 287 s->filepos = s->lma - low; 288 289 abfd->output_has_begun = true; 290 } 291 292 return _bfd_generic_set_section_contents (abfd, sec, data, offset, size); 293 } 294 295 /* No space is required for header information. */ 296 297 static int 298 binary_sizeof_headers (abfd, exec) 299 bfd *abfd; 300 boolean exec; 301 { 302 return 0; 303 } 304 305 #define binary_bfd_get_relocated_section_contents \ 306 bfd_generic_get_relocated_section_contents 307 #define binary_bfd_relax_section bfd_generic_relax_section 308 #define binary_bfd_link_hash_table_create _bfd_generic_link_hash_table_create 309 #define binary_bfd_link_add_symbols _bfd_generic_link_add_symbols 310 #define binary_bfd_final_link _bfd_generic_final_link 311 #define binary_bfd_link_split_section _bfd_generic_link_split_section 312 #define binary_get_section_contents_in_window \ 313 _bfd_generic_get_section_contents_in_window 314 315 const bfd_target binary_vec = 316 { 317 "binary", /* name */ 318 bfd_target_unknown_flavour, /* flavour */ 319 BFD_ENDIAN_UNKNOWN, /* byteorder */ 320 BFD_ENDIAN_UNKNOWN, /* header_byteorder */ 321 EXEC_P, /* object_flags */ 322 (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE | SEC_DATA 323 | SEC_ROM | SEC_HAS_CONTENTS), /* section_flags */ 324 0, /* symbol_leading_char */ 325 ' ', /* ar_pad_char */ 326 16, /* ar_max_namelen */ 327 bfd_getb64, bfd_getb_signed_64, bfd_putb64, 328 bfd_getb32, bfd_getb_signed_32, bfd_putb32, 329 bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */ 330 bfd_getb64, bfd_getb_signed_64, bfd_putb64, 331 bfd_getb32, bfd_getb_signed_32, bfd_putb32, 332 bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */ 333 { /* bfd_check_format */ 334 _bfd_dummy_target, 335 binary_object_p, /* bfd_check_format */ 336 _bfd_dummy_target, 337 _bfd_dummy_target, 338 }, 339 { /* bfd_set_format */ 340 bfd_false, 341 binary_mkobject, 342 bfd_false, 343 bfd_false, 344 }, 345 { /* bfd_write_contents */ 346 bfd_false, 347 bfd_true, 348 bfd_false, 349 bfd_false, 350 }, 351 352 BFD_JUMP_TABLE_GENERIC (binary), 353 BFD_JUMP_TABLE_COPY (_bfd_generic), 354 BFD_JUMP_TABLE_CORE (_bfd_nocore), 355 BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive), 356 BFD_JUMP_TABLE_SYMBOLS (binary), 357 BFD_JUMP_TABLE_RELOCS (binary), 358 BFD_JUMP_TABLE_WRITE (binary), 359 BFD_JUMP_TABLE_LINK (binary), 360 BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic), 361 362 NULL 363 }; 364