bfd/bfd.c

   1 /* Generic BFD library interface and support routines.
   2    Copyright (C) 1990-1991 Free Software Foundation, Inc.
   3    Written by Cygnus Support.
   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., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 /* $Id$ */
  22
  23 /*
  24 SECTION
  25         <<typedef bfd>>
  26
  27         A BFD is has type <<bfd>>; objects of this type are the
  28         cornerstone of any application using <<libbfd>>. References
  29         though the BFD and to data in the BFD give the entire BFD
  30         functionality.
  31
  32         Here is the struct used to define the type <<bfd>>.  This
  33         contains he major data about the file, and contains pointers
  34         to the rest of the data.
  35
  36 CODE_FRAGMENT
  37 .
  38 .struct _bfd
  39 .{
  40 .    {* The filename the application opened the BFD with.  *}
  41 .    CONST char *filename;
  42 .
  43 .    {* A pointer to the target jump table.             *}
  44 .    struct bfd_target *xvec;
  45 .
  46 .    {* To avoid dragging too many header files into every file that
  47 .       includes @file{bfd.h}, IOSTREAM has been declared as a "char
  48 .       *", and MTIME as a "long".  Their correct types, to which they
  49 .       are cast when used, are "FILE *" and "time_t".    The iostream
  50 .       is the result of an fopen on the filename. *}
  51 .    char *iostream;
  52 .
  53 .    {* Is the file being cached *}
  54 .
  55 .    boolean cacheable;
  56 .
  57 .    {* Marks whether there was a default target specified when the
  58 .       BFD was opened. This is used to select what matching algorithm
  59 .       to use to chose the back end. *}
  60 .
  61 .    boolean target_defaulted;
  62 .
  63 .    {* The caching routines use these to maintain a
  64 .       least-recently-used list of BFDs *}
  65 .
  66 .    struct _bfd *lru_prev, *lru_next;
  67 .
  68 .    {* When a file is closed by the caching routines, BFD retains
  69 .       state information on the file here:
  70 .     *}
  71 .
  72 .    file_ptr where;
  73 .
  74 .    {* and here:*}
  75 .
  76 .    boolean opened_once;
  77 .
  78 .    {* Set if we have a locally maintained mtime value, rather than
  79 .       getting it from the file each time: *}
  80 .
  81 .    boolean mtime_set;
  82 .
  83 .    {* File modified time, if mtime_set is true: *}
  84 .
  85 .    long mtime;
  86 .
  87 .    {* Reserved for an unimplemented file locking extension.*}
  88 .
  89 .    int ifd;
  90 .
  91 .    {* The format which belongs to the BFD.*}
  92 .
  93 .    bfd_format format;
  94 .
  95 .    {* The direction the BFD was opened with*}
  96 .
  97 .    enum bfd_direction {no_direction = 0,
  98 .                        read_direction = 1,
  99 .                        write_direction = 2,
 100 .                        both_direction = 3} direction;
 101 .
 102 .    {* Format_specific flags*}
 103 .
 104 .    flagword flags;
 105 .
 106 .    {* Currently my_archive is tested before adding origin to
 107 .       anything. I believe that this can become always an add of
 108 .       origin, with origin set to 0 for non archive files.   *}
 109 .
 110 .    file_ptr origin;
 111 .
 112 .    {* Remember when output has begun, to stop strange things
 113 .       happening. *}
 114 .    boolean output_has_begun;
 115 .
 116 .    {* Pointer to linked list of sections*}
 117 .    struct sec  *sections;
 118 .
 119 .    {* The number of sections *}
 120 .    unsigned int section_count;
 121 .
 122 .    {* Stuff only useful for object files:
 123 .       The start address. *}
 124 .    bfd_vma start_address;
 125 .
 126 .    {* Used for input and output*}
 127 .    unsigned int symcount;
 128 .
 129 .    {* Symbol table for output BFD*}
 130 .    struct symbol_cache_entry  **outsymbols;
 131 .
 132 .    {* Pointer to structure which contains architecture information*}
 133 .    struct bfd_arch_info *arch_info;
 134 .
 135 .    {* Stuff only useful for archives:*}
 136 .    PTR arelt_data;
 137 .    struct _bfd *my_archive;
 138 .    struct _bfd *next;
 139 .    struct _bfd *archive_head;
 140 .    boolean has_armap;
 141 .
 142 .    {* Used by the back end to hold private data. *}
 143 .
 144 .    union
 145 .      {
 146 .      struct aout_data_struct *aout_data;
 147 .      struct artdata *aout_ar_data;
 148 .      struct _oasys_data *oasys_obj_data;
 149 .      struct _oasys_ar_data *oasys_ar_data;
 150 .      struct coff_tdata *coff_obj_data;
 151 .      struct ieee_data_struct *ieee_data;
 152 .      struct ieee_ar_data_struct *ieee_ar_data;
 153 .      struct srec_data_struct *srec_data;
 154 .      struct elf_obj_tdata_struct *elf_obj_data;
 155 .      struct elf_core_tdata_struct *elf_core_data;
 156 .      struct bout_data_struct *bout_data;
 157 .      struct sun_core_struct *sun_core_data;
 158 .      struct trad_core_struct *trad_core_data;
 159 .      PTR any;
 160 .      } tdata;
 161 .
 162 .    {* Used by the application to hold private data*}
 163 .    PTR usrdata;
 164 .
 165 .    {* Where all the allocated stuff under this BFD goes *}
 166 .    struct obstack memory;
 167 .
 168 .    asymbol **ld_symbols;
 169 .};
 170 .
 171 */
 172
 173 #include "bfd.h"
 174 #include "sysdep.h"
 175 #include "libbfd.h"
 176
 177 #undef strerror
 178 extern char *strerror();
 179
 180
 181 CONST short _bfd_host_big_endian = 0x0100;
 182         /* Accessing the above as (*(char*)&_bfd_host_big_endian), will
 183            return 1 if the host is big-endian, 0 otherwise.
 184            (assuming that a short is two bytes long!!!  FIXME)
 185            (See HOST_IS_BIG_ENDIAN_P in bfd.h.)  */
 186 \f
 187 /** Error handling
 188     o - Most functions return nonzero on success (check doc for
 189         precise semantics); 0 or NULL on error.
 190     o - Internal errors are documented by the value of bfd_error.
 191         If that is system_call_error then check errno.
 192     o - The easiest way to report this to the user is to use bfd_perror.
 193 */
 194
 195 bfd_ec bfd_error = no_error;
 196
 197 char *bfd_errmsgs[] = { "No error",
 198                         "System call error",
 199                         "Invalid target",
 200                         "File in wrong format",
 201                         "Invalid operation",
 202                         "Memory exhausted",
 203                         "No symbols",
 204                         "No relocation info",
 205                         "No more archived files",
 206                         "Malformed archive",
 207                         "Symbol not found",
 208                         "File format not recognized",
 209                         "File format is ambiguous",
 210                         "Section has no contents",
 211                         "Nonrepresentable section on output",
 212                         "Symbol needs debug section which does not exist",
 213                         "#<Invalid error code>"
 214                        };
 215
 216 static
 217 void
 218 DEFUN(bfd_nonrepresentable_section,(abfd, name),
 219          CONST  bfd * CONST abfd AND
 220          CONST  char * CONST name)
 221 {
 222   printf("bfd error writing file %s, format %s can't represent section %s\n",
 223          abfd->filename,
 224          abfd->xvec->name,
 225          name);
 226   exit(1);
 227 }
 228
 229 static
 230 void
 231 DEFUN(bfd_undefined_symbol,(relent, seclet),
 232       CONST  arelent *relent AND
 233       CONST  struct bfd_seclet_struct *seclet)
 234 {
 235   asymbol *symbol = *(relent->sym_ptr_ptr);
 236   printf("bfd error relocating, symbol %s is undefined\n",
 237          symbol->name);
 238   exit(1);
 239 }
 240 static
 241 void
 242 DEFUN(bfd_reloc_value_truncated,(relent, seclet),
 243          CONST  arelent *relent AND
 244       struct bfd_seclet_struct *seclet)
 245 {
 246   asymbol *symbol = *(relent->sym_ptr_ptr);
 247   printf("bfd error relocating, value truncated\n");
 248   exit(1);
 249 }
 250 static
 251 void
 252 DEFUN(bfd_reloc_is_dangerous,(relent, seclet),
 253       CONST  arelent *relent AND
 254      CONST  struct bfd_seclet_struct *seclet)
 255 {
 256   asymbol *symbol = *(relent->sym_ptr_ptr);
 257   printf("bfd error relocating, dangerous\n");
 258   exit(1);
 259 }
 260
 261 bfd_error_vector_type bfd_error_vector =
 262   {
 263   bfd_nonrepresentable_section ,
 264   bfd_undefined_symbol,
 265   bfd_reloc_value_truncated,
 266   bfd_reloc_is_dangerous,
 267   };
 268
 269
 270 char *
 271 bfd_errmsg (error_tag)
 272      bfd_ec error_tag;
 273 {
 274 #ifndef errno
 275   extern int errno;
 276 #endif
 277   if (error_tag == system_call_error)
 278     return strerror (errno);
 279
 280   if ((((int)error_tag <(int) no_error) ||
 281        ((int)error_tag > (int)invalid_error_code)))
 282     error_tag = invalid_error_code;/* sanity check */
 283
 284   return bfd_errmsgs [(int)error_tag];
 285 }
 286
 287
 288 void bfd_default_error_trap(error_tag)
 289 bfd_ec error_tag;
 290 {
 291   printf("bfd assert fail (%s)\n", bfd_errmsg(error_tag));
 292 }
 293
 294 void (*bfd_error_trap)() = bfd_default_error_trap;
 295 void (*bfd_error_nonrepresentabltrap)() = bfd_default_error_trap;
 296
 297 void
 298 DEFUN(bfd_perror,(message),
 299       CONST char *message)
 300 {
 301   if (bfd_error == system_call_error)
 302     perror((char *)message);            /* must be system error then... */
 303   else {
 304     if (message == NULL || *message == '\0')
 305       fprintf (stderr, "%s\n", bfd_errmsg (bfd_error));
 306     else
 307       fprintf (stderr, "%s: %s\n", message, bfd_errmsg (bfd_error));
 308   }
 309 }
 310
 311  \f
 312 /** Symbols */
 313
 314
 315 /*
 316 FUNCTION
 317         bfd_get_reloc_upper_bound
 318
 319 SYNOPSIS
 320         unsigned int bfd_get_reloc_upper_bound(bfd *abfd, asection *sect);
 321
 322 DESCRIPTION
 323         This function return the number of bytes required to store the
 324         relocation information associated with section <<sect>>
 325         attached to bfd <<abfd>>
 326
 327 */
 328
 329
 330 unsigned int
 331 DEFUN(bfd_get_reloc_upper_bound,(abfd, asect),
 332      bfd *abfd AND
 333      sec_ptr asect)
 334 {
 335   if (abfd->format != bfd_object) {
 336     bfd_error = invalid_operation;
 337     return 0;
 338   }
 339
 340   return BFD_SEND (abfd, _get_reloc_upper_bound, (abfd, asect));
 341 }
 342
 343 /*
 344 FUNCTION
 345         bfd_canonicalize_reloc
 346
 347 SYNOPSIS
 348         unsigned int bfd_canonicalize_reloc
 349                 (bfd *abfd,
 350                 asection *sec,
 351                 arelent **loc,
 352                 asymbol **syms);
 353
 354 DESCRIPTION
 355         This function calls the back end associated with the open
 356         <<abfd>> and translates the external form of the relocation
 357         information attached to <<sec>> into the internal canonical
 358         form.  The table is placed into memory at <<loc>>, which has
 359         been preallocated, usually by a call to
 360         <<bfd_get_reloc_upper_bound>>.
 361
 362         The <<syms>> table is also needed for horrible internal magic
 363         reasons.
 364
 365
 366 */
 367 unsigned int
 368 DEFUN(bfd_canonicalize_reloc,(abfd, asect, location, symbols),
 369      bfd *abfd AND
 370      sec_ptr asect AND
 371      arelent **location AND
 372      asymbol **symbols)
 373 {
 374     if (abfd->format != bfd_object) {
 375             bfd_error = invalid_operation;
 376             return 0;
 377         }
 378     return BFD_SEND (abfd, _bfd_canonicalize_reloc,
 379                      (abfd, asect, location, symbols));
 380 }
 381
 382
 383 /*
 384 FUNCTION
 385         bfd_set_file_flags
 386
 387 SYNOPSIS
 388         boolean bfd_set_file_flags(bfd *abfd, flagword flags);
 389
 390 DESCRIPTION
 391         This function attempts to set the flag word in the referenced
 392         BFD structure to the value supplied.
 393
 394         Possible errors are:
 395         o wrong_format - The target bfd was not of object format.
 396         o invalid_operation - The target bfd was open for reading.
 397         o invalid_operation -
 398         The flag word contained a bit which was not applicable to the
 399         type of file. eg, an attempt was made to set the D_PAGED bit
 400         on a bfd format which does not support demand paging
 401
 402 */
 403
 404 boolean
 405 bfd_set_file_flags (abfd, flags)
 406      bfd *abfd;
 407      flagword flags;
 408 {
 409   if (abfd->format != bfd_object) {
 410     bfd_error = wrong_format;
 411     return false;
 412   }
 413
 414   if (bfd_read_p (abfd)) {
 415     bfd_error = invalid_operation;
 416     return false;
 417   }
 418
 419   if ((flags & bfd_applicable_file_flags (abfd)) != flags) {
 420     bfd_error = invalid_operation;
 421     return false;
 422   }
 423
 424   bfd_get_file_flags (abfd) = flags;
 425 return true;
 426 }
 427
 428 /*
 429 FUNCTION
 430         bfd_set_reloc
 431
 432 SYNOPSIS
 433         void bfd_set_reloc
 434           (bfd *abfd, asection *sec, arelent **rel, unsigned int count)
 435
 436 DESCRIPTION
 437         This function sets the relocation pointer and count within a
 438         section to the supplied values.
 439
 440 */
 441
 442 void
 443 bfd_set_reloc (ignore_abfd, asect, location, count)
 444      bfd *ignore_abfd;
 445      sec_ptr asect;
 446      arelent **location;
 447      unsigned int count;
 448 {
 449   asect->orelocation  = location;
 450   asect->reloc_count = count;
 451 }
 452
 453 void
 454 bfd_assert(file, line)
 455 char *file;
 456 int line;
 457 {
 458   printf("bfd assertion fail %s:%d\n",file,line);
 459 }
 460
 461
 462 /*
 463 FUNCTION
 464         bfd_set_start_address
 465
 466 DESCRIPTION
 467         Marks the entry point of an output BFD.
 468
 469 RETURNS
 470         Returns <<true>> on success, <<false>> otherwise.
 471
 472 SYNOPSIS
 473         boolean bfd_set_start_address(bfd *, bfd_vma);
 474 */
 475
 476 boolean
 477 bfd_set_start_address(abfd, vma)
 478 bfd *abfd;
 479 bfd_vma vma;
 480 {
 481   abfd->start_address = vma;
 482   return true;
 483 }
 484
 485
 486 /*
 487 FUNCTION
 488         The bfd_get_mtime function
 489
 490 SYNOPSIS
 491         long bfd_get_mtime(bfd *);
 492
 493 DESCRIPTION
 494         Return file modification time (as read from file system, or
 495         from archive header for archive members).
 496
 497 */
 498
 499 long
 500 bfd_get_mtime (abfd)
 501      bfd *abfd;
 502 {
 503   FILE *fp;
 504   struct stat buf;
 505
 506   if (abfd->mtime_set)
 507     return abfd->mtime;
 508
 509   fp = bfd_cache_lookup (abfd);
 510   if (0 != fstat (fileno (fp), &buf))
 511     return 0;
 512
 513   abfd->mtime = buf.st_mtime;           /* Save value in case anyone wants it */
 514   return buf.st_mtime;
 515 }
 516
 517 /*
 518 FUNCTION
 519         stuff
 520
 521 DESCRIPTION
 522         stuff which should be documented
 523
 524 .#define bfd_sizeof_headers(abfd, reloc) \
 525 .     BFD_SEND (abfd, _bfd_sizeof_headers, (abfd, reloc))
 526 .
 527 .#define bfd_find_nearest_line(abfd, sec, syms, off, file, func, line) \
 528 .     BFD_SEND (abfd, _bfd_find_nearest_line,  (abfd, sec, syms, off, file, func, line))
 529 .
 530 .#define bfd_debug_info_start(abfd) \
 531 .        BFD_SEND (abfd, _bfd_debug_info_start, (abfd))
 532 .
 533 .#define bfd_debug_info_end(abfd) \
 534 .        BFD_SEND (abfd, _bfd_debug_info_end, (abfd))
 535 .
 536 .#define bfd_debug_info_accumulate(abfd, section) \
 537 .        BFD_SEND (abfd, _bfd_debug_info_accumulate, (abfd, section))
 538 .
 539 .#define bfd_stat_arch_elt(abfd, stat) \
 540 .        BFD_SEND (abfd, _bfd_stat_arch_elt,(abfd, stat))
 541 .
 542 .#define bfd_coff_swap_aux_in(a,e,t,c,i) \
 543 .        BFD_SEND (a, _bfd_coff_swap_aux_in, (a,e,t,c,i))
 544 .
 545 .#define bfd_coff_swap_sym_in(a,e,i) \
 546 .        BFD_SEND (a, _bfd_coff_swap_sym_in, (a,e,i))
 547 .
 548 .#define bfd_coff_swap_lineno_in(a,e,i) \
 549 .        BFD_SEND ( a, _bfd_coff_swap_lineno_in, (a,e,i))
 550 .
 551 .#define bfd_set_arch_mach(abfd, arch, mach)\
 552 .        BFD_SEND ( abfd, _bfd_set_arch_mach, (abfd, arch, mach))
 553 .
 554 .#define bfd_coff_swap_reloc_out(abfd, i, o) \
 555 .        BFD_SEND (abfd, _bfd_coff_swap_reloc_out, (abfd, i, o))
 556 .
 557 .#define bfd_coff_swap_lineno_out(abfd, i, o) \
 558 .        BFD_SEND (abfd, _bfd_coff_swap_lineno_out, (abfd, i, o))
 559 .
 560 .#define bfd_coff_swap_aux_out(abfd, i, t,c,o) \
 561 .        BFD_SEND (abfd, _bfd_coff_swap_aux_out, (abfd, i,t,c, o))
 562 .
 563 .#define bfd_coff_swap_sym_out(abfd, i,o) \
 564 .        BFD_SEND (abfd, _bfd_coff_swap_sym_out, (abfd, i, o))
 565 .
 566 .#define bfd_coff_swap_scnhdr_out(abfd, i,o) \
 567 .        BFD_SEND (abfd, _bfd_coff_swap_scnhdr_out, (abfd, i, o))
 568 .
 569 .#define bfd_coff_swap_filehdr_out(abfd, i,o) \
 570 .        BFD_SEND (abfd, _bfd_coff_swap_filehdr_out, (abfd, i, o))
 571 .
 572 .#define bfd_coff_swap_aouthdr_out(abfd, i,o) \
 573 .        BFD_SEND (abfd, _bfd_coff_swap_aouthdr_out, (abfd, i, o))
 574 .
 575 .#define bfd_get_relocated_section_contents(abfd, seclet) \
 576 .       BFD_SEND (abfd, _bfd_get_relocated_section_contents, (abfd, seclet))
 577 .
 578 .#define bfd_relax_section(abfd, section, symbols) \
 579 .       BFD_SEND (abfd, _bfd_relax_section, (abfd, section, symbols))
 580
 581 */
 582
 583
 584
 585
 586
 587