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 DESCRIPTION
  28         A BFD is has type <<bfd>>; objects of this type are the
  29         cornerstone of any application using <<libbfd>>. References
  30         though the BFD and to data in the BFD give the entire BFD
  31         functionality.
  32
  33         Here is the struct used to define the type <<bfd>>.  This
  34         contains he major data about the file, and contains pointers
  35         to the rest of the data.
  36
  37 .struct _bfd
  38 .{
  39         The filename the application opened the BFD with.
  40
  41 .  CONST char *filename;
  42
  43         A pointer to the target jump table.
  44
  45 .  struct bfd_target *xvec;
  46
  47         To avoid dragging too many header files into every file that
  48         includes @file{bfd.h}, IOSTREAM has been declared as a "char
  49         *", and MTIME as a "long".  Their correct types, to which they
  50         are cast when used, are "FILE *" and "time_t".    The iostream
  51         is the result of an fopen on the filename.
  52
  53 .  char *iostream;
  54
  55 Is the file being cached @xref{File Caching}.
  56
  57 .  boolean cacheable;
  58
  59         Marks whether there was a default target specified when the
  60         BFD was opened. This is used to select what matching algorithm
  61         to use to chose the back end.
  62
  63 .  boolean target_defaulted;
  64
  65         The caching routines use these to maintain a
  66         least-recently-used list of BFDs (@pxref{File Caching}).
  67
  68 .  struct _bfd *lru_prev, *lru_next;
  69
  70         When a file is closed by the caching routines, BFD retains
  71         state information on the file here:
  72
  73 .  file_ptr where;
  74
  75         and here:
  76
  77 .  boolean opened_once;
  78
  79 .  boolean mtime_set;
  80
  81 File modified time
  82
  83 .  long mtime;
  84
  85         Reserved for an unimplemented file locking extension.
  86
  87 .  int ifd;
  88
  89         The format which belongs to the BFD.
  90
  91 .  bfd_format format;
  92
  93         The direction the BFD was opened with
  94
  95 .  enum bfd_direction {no_direction = 0,
  96 .                       read_direction = 1,
  97 .                       write_direction = 2,
  98 .                       both_direction = 3} direction;
  99
 100         Format_specific flags
 101
 102 .  flagword flags;
 103
 104         Currently my_archive is tested before adding origin to
 105         anything. I believe that this can become always an add of
 106         origin, with origin set to 0 for non archive files.
 107
 108 .  file_ptr origin;
 109
 110         Remember when output has begun, to stop strange things happening.
 111
 112 .  boolean output_has_begun;
 113
 114         Pointer to linked list of sections
 115
 116 .  struct sec  *sections;
 117
 118         The number of sections
 119
 120 .  unsigned int section_count;
 121
 122         Stuff only useful for object files:
 123         The start address.
 124
 125 .  bfd_vma start_address;
 126
 127         Used for input and output
 128
 129 .  unsigned int symcount;
 130
 131         Symbol table for output BFD
 132
 133 .  struct symbol_cache_entry  **outsymbols;
 134
 135         Pointer to structure which contains architecture information
 136
 137 .  struct bfd_arch_info *arch_info;
 138
 139         Stuff only useful for archives:
 140
 141 .  PTR arelt_data;
 142 .  struct _bfd *my_archive;
 143 .  struct _bfd *next;
 144 .  struct _bfd *archive_head;
 145 .  boolean has_armap;
 146
 147         Used by the back end to hold private data.
 148
 149 .  PTR tdata;
 150
 151         Used by the application to hold private data
 152
 153 .  PTR usrdata;
 154
 155         Where all the allocated stuff under this BFD goes
 156         (@pxref{Memory Usage}).
 157
 158 .  struct obstack memory;
 159 .};
 160
 161 */
 162 #include "bfd.h"
 163 #include "sysdep.h"
 164 #include "libbfd.h"
 165
 166 #undef strerror
 167 extern char *strerror();
 168
 169
 170 CONST short _bfd_host_big_endian = 0x0100;
 171         /* Accessing the above as (*(char*)&_bfd_host_big_endian), will
 172            return 1 if the host is big-endian, 0 otherwise.
 173            (assuming that a short is two bytes long!!!  FIXME)
 174            (See HOST_IS_BIG_ENDIAN_P in bfd.h.)  */
 175 \f
 176 /** Error handling
 177     o - Most functions return nonzero on success (check doc for
 178         precise semantics); 0 or NULL on error.
 179     o - Internal errors are documented by the value of bfd_error.
 180         If that is system_call_error then check errno.
 181     o - The easiest way to report this to the user is to use bfd_perror.
 182 */
 183
 184 bfd_ec bfd_error = no_error;
 185
 186 char *bfd_errmsgs[] = { "No error",
 187                         "System call error",
 188                         "Invalid target",
 189                         "File in wrong format",
 190                         "Invalid operation",
 191                         "Memory exhausted",
 192                         "No symbols",
 193                         "No relocation info",
 194                         "No more archived files",
 195                         "Malformed archive",
 196                         "Symbol not found",
 197                         "File format not recognized",
 198                         "File format is ambiguous",
 199                         "Section has no contents",
 200                         "Nonrepresentable section on output",
 201                         "Symbol needs debug section which does not exist",
 202                         "#<Invalid error code>"
 203                        };
 204
 205 static
 206 void
 207 DEFUN(bfd_nonrepresentable_section,(abfd, name),
 208          CONST  bfd * CONST abfd AND
 209          CONST  char * CONST name)
 210 {
 211   printf("bfd error writing file %s, format %s can't represent section %s\n",
 212          abfd->filename,
 213          abfd->xvec->name,
 214          name);
 215   exit(1);
 216 }
 217
 218 bfd_error_vector_type bfd_error_vector =
 219   {
 220   bfd_nonrepresentable_section
 221   };
 222
 223 char *
 224 bfd_errmsg (error_tag)
 225      bfd_ec error_tag;
 226 {
 227 #ifndef errno
 228   extern int errno;
 229 #endif
 230   if (error_tag == system_call_error)
 231     return strerror (errno);
 232
 233   if ((((int)error_tag <(int) no_error) ||
 234        ((int)error_tag > (int)invalid_error_code)))
 235     error_tag = invalid_error_code;/* sanity check */
 236
 237   return bfd_errmsgs [(int)error_tag];
 238 }
 239
 240
 241 void bfd_default_error_trap(error_tag)
 242 bfd_ec error_tag;
 243 {
 244   printf("bfd assert fail (%s)\n", bfd_errmsg(error_tag));
 245 }
 246
 247 void (*bfd_error_trap)() = bfd_default_error_trap;
 248 void (*bfd_error_nonrepresentabltrap)() = bfd_default_error_trap;
 249
 250 void
 251 DEFUN(bfd_perror,(message),
 252       CONST char *message)
 253 {
 254   if (bfd_error == system_call_error)
 255     perror((char *)message);            /* must be system error then... */
 256   else {
 257     if (message == NULL || *message == '\0')
 258       fprintf (stderr, "%s\n", bfd_errmsg (bfd_error));
 259     else
 260       fprintf (stderr, "%s: %s\n", message, bfd_errmsg (bfd_error));
 261   }
 262 }
 263
 264  \f
 265 /** Symbols */
 266
 267 /* returns the number of octets of storage required */
 268
 269 unsigned int
 270 get_reloc_upper_bound (abfd, asect)
 271      bfd *abfd;
 272      sec_ptr asect;
 273 {
 274   if (abfd->format != bfd_object) {
 275     bfd_error = invalid_operation;
 276     return 0;
 277   }
 278
 279   return BFD_SEND (abfd, _get_reloc_upper_bound, (abfd, asect));
 280 }
 281
 282 unsigned int
 283 DEFUN(bfd_canonicalize_reloc,(abfd, asect, location, symbols),
 284      bfd *abfd AND
 285      sec_ptr asect AND
 286      arelent **location AND
 287      asymbol **symbols)
 288 {
 289     if (abfd->format != bfd_object) {
 290         bfd_error = invalid_operation;
 291         return 0;
 292     }
 293     return BFD_SEND (abfd, _bfd_canonicalize_reloc, (abfd, asect, location, symbols));
 294 }
 295
 296
 297 boolean
 298 bfd_set_file_flags (abfd, flags)
 299      bfd *abfd;
 300      flagword flags;
 301 {
 302   if (abfd->format != bfd_object) {
 303     bfd_error = wrong_format;
 304     return false;
 305   }
 306
 307   if (bfd_read_p (abfd)) {
 308     bfd_error = invalid_operation;
 309     return false;
 310   }
 311
 312   if ((flags & bfd_applicable_file_flags (abfd)) != flags) {
 313     bfd_error = invalid_operation;
 314     return false;
 315   }
 316
 317   bfd_get_file_flags (abfd) = flags;
 318 return true;
 319 }
 320
 321
 322 void
 323 bfd_set_reloc (ignore_abfd, asect, location, count)
 324      bfd *ignore_abfd;
 325      sec_ptr asect;
 326      arelent **location;
 327      unsigned int count;
 328 {
 329   asect->orelocation  = location;
 330   asect->reloc_count = count;
 331 }
 332
 333 void
 334 bfd_assert(file, line)
 335 char *file;
 336 int line;
 337 {
 338   printf("bfd assertion fail %s:%d\n",file,line);
 339 }
 340
 341
 342 /*
 343 FUNCTION
 344         bfd_set_start_address
 345
 346 DESCRIPTION
 347
 348         Marks the entry point of an output BFD.
 349
 350 RETURNS
 351         Returns <<true>> on success, <<false>> otherwise.
 352
 353 SYNOPSIS
 354         boolean bfd_set_start_address(bfd *, bfd_vma);
 355 */
 356
 357 boolean
 358 bfd_set_start_address(abfd, vma)
 359 bfd *abfd;
 360 bfd_vma vma;
 361 {
 362   abfd->start_address = vma;
 363   return true;
 364 }
 365
 366
 367 /*
 368 FUNCTION
 369         bfd_get_mtime
 370
 371 DESCRIPTION
 372         Return cached file modification time (e.g. as read from
 373         archive header for archive members, or from file system if we
 374         have been called before); else determine modify time, cache
 375         it, and return it.
 376
 377 SYNOPSIS
 378         long bfd_get_mtime(bfd *);
 379 */
 380
 381 long
 382 bfd_get_mtime (abfd)
 383      bfd *abfd;
 384 {
 385   FILE *fp;
 386   struct stat buf;
 387
 388   if (abfd->mtime_set)
 389     return abfd->mtime;
 390
 391   fp = bfd_cache_lookup (abfd);
 392   if (0 != fstat (fileno (fp), &buf))
 393     return 0;
 394
 395   abfd->mtime_set = true;
 396   abfd->mtime = buf.st_mtime;
 397   return abfd->mtime;
 398 }
 399
 400 /*
 401 FUNCTION
 402         stuff
 403
 404 DESCRIPTION
 405         stuff which should be documented
 406
 407 .#define bfd_sizeof_headers(abfd, reloc) \
 408 .     BFD_SEND (abfd, _bfd_sizeof_headers, (abfd, reloc))
 409 .
 410 .#define bfd_find_nearest_line(abfd, section, symbols, offset, filename_ptr, func, line_ptr) \
 411 .     BFD_SEND (abfd, _bfd_find_nearest_line,  (abfd, section, symbols, offset, filename_ptr, func, line_ptr))
 412 .
 413 .#define bfd_debug_info_start(abfd) \
 414 .        BFD_SEND (abfd, _bfd_debug_info_start, (abfd))
 415 .
 416 .#define bfd_debug_info_end(abfd) \
 417 .        BFD_SEND (abfd, _bfd_debug_info_end, (abfd))
 418 .
 419 .#define bfd_debug_info_accumulate(abfd, section) \
 420 .        BFD_SEND (abfd, _bfd_debug_info_accumulate, (abfd, section))
 421 .
 422 .#define bfd_stat_arch_elt(abfd, stat) \
 423 .        BFD_SEND (abfd, _bfd_stat_arch_elt,(abfd, stat))
 424 .
 425 .#define bfd_coff_swap_aux_in(a,e,t,c,i) \
 426 .        BFD_SEND (a, _bfd_coff_swap_aux_in, (a,e,t,c,i))
 427 .
 428 .#define bfd_coff_swap_sym_in(a,e,i) \
 429 .        BFD_SEND (a, _bfd_coff_swap_sym_in, (a,e,i))
 430 .
 431 .#define bfd_coff_swap_lineno_in(a,e,i) \
 432 .        BFD_SEND ( a, _bfd_coff_swap_lineno_in, (a,e,i))
 433 .
 434 .#define bfd_set_arch_mach(abfd, arch, mach)\
 435 .        BFD_SEND ( abfd, _bfd_set_arch_mach, (abfd, arch, mach))
 436 .
 437 .#define bfd_coff_swap_reloc_out(abfd, i, o) \
 438 .        BFD_SEND (abfd, _bfd_coff_swap_reloc_out, (abfd, i, o))
 439 .
 440 .#define bfd_coff_swap_lineno_out(abfd, i, o) \
 441 .        BFD_SEND (abfd, _bfd_coff_swap_lineno_out, (abfd, i, o))
 442 .
 443 .#define bfd_coff_swap_aux_out(abfd, i, t,c,o) \
 444 .        BFD_SEND (abfd, _bfd_coff_swap_aux_out, (abfd, i,t,c, o))
 445 .
 446 .#define bfd_coff_swap_sym_out(abfd, i,o) \
 447 .        BFD_SEND (abfd, _bfd_coff_swap_sym_out, (abfd, i, o))
 448 .
 449 .#define bfd_coff_swap_scnhdr_out(abfd, i,o) \
 450 .        BFD_SEND (abfd, _bfd_coff_swap_scnhdr_out, (abfd, i, o))
 451 .
 452 .#define bfd_coff_swap_filehdr_out(abfd, i,o) \
 453 .        BFD_SEND (abfd, _bfd_coff_swap_filehdr_out, (abfd, i, o))
 454 .
 455 .#define bfd_coff_swap_aouthdr_out(abfd, i,o) \
 456 .        BFD_SEND (abfd, _bfd_coff_swap_aouthdr_out, (abfd, i, o))
 457 .
 458 */
 459
 460
 461
 462
 463
 464