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 /*proto*
  24 @section @code{typedef bfd}
  25
  26 A BFD is has type @code{bfd}; objects of this type are the cornerstone
  27 of any application using @code{libbfd}. References though the BFD and
  28 to data in the BFD give the entire BFD functionality.
  29
  30 Here is the struct used to define the type @code{bfd}.  This contains
  31 the major data about the file, and contains pointers to the rest of
  32 the data.
  33
  34 *+++
  35
  36 $struct _bfd
  37 ${
  38   The filename the application opened the BFD with.
  39
  40 $  CONST char *filename;
  41
  42 A pointer to the target jump table.
  43
  44 $  struct bfd_target *xvec;
  45
  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 *", and MTIME
  49 as a "long".  Their correct types, to which they are cast when used,
  50 are "FILE *" and "time_t".
  51
  52 The iostream is the result of an fopen on the filename.
  53
  54 $  char *iostream;
  55
  56 Is the file being cached @xref{File Caching}.
  57
  58 $  boolean cacheable;
  59
  60 Marks whether there was a default target specified when the BFD was
  61 opened. This is used to select what matching algorithm to use to chose
  62 the back end.
  63
  64 $  boolean target_defaulted;
  65
  66 The caching routines use these to maintain a least-recently-used list of
  67 BFDs (@pxref{File Caching}).
  68
  69 $  struct _bfd *lru_prev, *lru_next;
  70
  71 When a file is closed by the caching routines, BFD retains state
  72 information on the file here:
  73
  74 $  file_ptr where;
  75
  76 and here:
  77
  78 $  boolean opened_once;
  79
  80 $  boolean mtime_set;
  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 anything. I
 105 believe that this can become always an add of origin, with origin set
 106 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 Used for input and output
 127
 128 $  unsigned int symcount;
 129 Symbol table for output BFD
 130
 131 $  struct symbol_cache_entry  **outsymbols;
 132
 133 Pointer to structure which contains architecture information
 134
 135 $  struct bfd_arch_info *arch_info;
 136
 137 Stuff only useful for archives:
 138
 139 $  PTR arelt_data;
 140 $  struct _bfd *my_archive;
 141 $  struct _bfd *next;
 142 $  struct _bfd *archive_head;
 143 $  boolean has_armap;
 144
 145 Used by the back end to hold private data.
 146
 147 $  PTR tdata;
 148
 149 Used by the application to hold private data
 150
 151 $  PTR usrdata;
 152
 153 Where all the allocated stuff under this BFD goes (@pxref{Memory Usage}).
 154
 155 $  struct obstack memory;
 156 $};
 157
 158 *---
 159
 160 */
 161 #include "bfd.h"
 162 #include "sysdep.h"
 163 #include "libbfd.h"
 164
 165 #undef strerror
 166 extern char *strerror();
 167
 168
 169 short _bfd_host_big_endian = 0x0100;
 170         /* Accessing the above as (*(char*)&_bfd_host_big_endian), will
 171            return 1 if the host is big-endian, 0 otherwise.
 172            (assuming that a short is two bytes long!!!  FIXME)
 173            (See HOST_IS_BIG_ENDIAN_P in bfd.h.)  */
 174 \f
 175 /** Error handling
 176     o - Most functions return nonzero on success (check doc for
 177         precise semantics); 0 or NULL on error.
 178     o - Internal errors are documented by the value of bfd_error.
 179         If that is system_call_error then check errno.
 180     o - The easiest way to report this to the user is to use bfd_perror.
 181 */
 182
 183 bfd_ec bfd_error = no_error;
 184
 185 char *bfd_errmsgs[] = { "No error",
 186                         "System call error",
 187                         "Invalid target",
 188                         "File in wrong format",
 189                         "Invalid operation",
 190                         "Memory exhausted",
 191                         "No symbols",
 192                         "No relocation info",
 193                         "No more archived files",
 194                         "Malformed archive",
 195                         "Symbol not found",
 196                         "File format not recognized",
 197                         "File format is ambiguous",
 198                         "Section has no contents",
 199                         "Nonrepresentable section on output",
 200                         "Symbol needs debug section which does not exist",
 201                         "#<Invalid error code>"
 202                        };
 203
 204 static
 205 void
 206 DEFUN(bfd_nonrepresentable_section,(abfd, name),
 207          CONST  bfd * CONST abfd AND
 208          CONST  char * CONST name)
 209 {
 210   printf("bfd error writing file %s, format %s can't represent section %s\n",
 211          abfd->filename,
 212          abfd->xvec->name,
 213          name);
 214   exit(1);
 215 }
 216
 217 bfd_error_vector_type bfd_error_vector =
 218   {
 219   bfd_nonrepresentable_section
 220   };
 221
 222 char *
 223 bfd_errmsg (error_tag)
 224      bfd_ec error_tag;
 225 {
 226 #ifndef errno
 227   extern int errno;
 228 #endif
 229   if (error_tag == system_call_error)
 230     return strerror (errno);
 231
 232   if ((((int)error_tag <(int) no_error) ||
 233        ((int)error_tag > (int)invalid_error_code)))
 234     error_tag = invalid_error_code;/* sanity check */
 235
 236   return bfd_errmsgs [(int)error_tag];
 237 }
 238
 239
 240 void bfd_default_error_trap(error_tag)
 241 bfd_ec error_tag;
 242 {
 243   printf("bfd assert fail (%s)\n", bfd_errmsg(error_tag));
 244 }
 245
 246 void (*bfd_error_trap)() = bfd_default_error_trap;
 247 void (*bfd_error_nonrepresentabltrap)() = bfd_default_error_trap;
 248
 249 void
 250 DEFUN(bfd_perror,(message),
 251       CONST char *message)
 252 {
 253   if (bfd_error == system_call_error)
 254     perror((char *)message);            /* must be system error then... */
 255   else {
 256     if (message == NULL || *message == '\0')
 257       fprintf (stderr, "%s\n", bfd_errmsg (bfd_error));
 258     else
 259       fprintf (stderr, "%s: %s\n", message, bfd_errmsg (bfd_error));
 260   }
 261 }
 262
 263  \f
 264 /** Symbols */
 265
 266 /* returns the number of octets of storage required */
 267
 268 unsigned int
 269 get_reloc_upper_bound (abfd, asect)
 270      bfd *abfd;
 271      sec_ptr asect;
 272 {
 273   if (abfd->format != bfd_object) {
 274     bfd_error = invalid_operation;
 275     return 0;
 276   }
 277
 278   return BFD_SEND (abfd, _get_reloc_upper_bound, (abfd, asect));
 279 }
 280
 281 unsigned int
 282 bfd_canonicalize_reloc (abfd, asect, location, symbols)
 283      bfd *abfd;
 284      sec_ptr asect;
 285      arelent **location;
 286      asymbol **symbols;
 287 {
 288   if (abfd->format != bfd_object) {
 289     bfd_error = invalid_operation;
 290     return 0;
 291   }
 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 /*proto* bfd_set_start_address
 343
 344 Marks the entry point of an output BFD. Returns @code{true} on
 345 success, @code{false} otherwise.
 346
 347 *; PROTO(boolean, bfd_set_start_address,(bfd *, bfd_vma));
 348 */
 349
 350 boolean
 351 bfd_set_start_address(abfd, vma)
 352 bfd *abfd;
 353 bfd_vma vma;
 354 {
 355   abfd->start_address = vma;
 356   return true;
 357 }
 358
 359
 360 /*proto*  bfd_get_mtime
 361
 362 Return cached file modification time (e.g. as read from archive header
 363 for archive members, or from file system if we have been called
 364 before); else determine modify time, cache it, and return it.
 365
 366 *; PROTO(long, bfd_get_mtime, (bfd *));
 367
 368 */
 369
 370 long
 371 bfd_get_mtime (abfd)
 372      bfd *abfd;
 373 {
 374   FILE *fp;
 375   struct stat buf;
 376
 377   if (abfd->mtime_set)
 378     return abfd->mtime;
 379
 380   fp = bfd_cache_lookup (abfd);
 381   if (0 != fstat (fileno (fp), &buf))
 382     return 0;
 383
 384   abfd->mtime_set = true;
 385   abfd->mtime = buf.st_mtime;
 386   return abfd->mtime;
 387 }
 388
 389 /*proto* stuff
 390
 391 *+
 392
 393 #define bfd_sizeof_headers(abfd, reloc) \
 394      BFD_SEND (abfd, _bfd_sizeof_headers, (abfd, reloc))
 395
 396 #define bfd_find_nearest_line(abfd, section, symbols, offset, filename_ptr, func, line_ptr) \
 397      BFD_SEND (abfd, _bfd_find_nearest_line,  (abfd, section, symbols, offset, filename_ptr, func, line_ptr))
 398
 399 #define bfd_debug_info_start(abfd) \
 400         BFD_SEND (abfd, _bfd_debug_info_start, (abfd))
 401
 402 #define bfd_debug_info_end(abfd) \
 403         BFD_SEND (abfd, _bfd_debug_info_end, (abfd))
 404
 405 #define bfd_debug_info_accumulate(abfd, section) \
 406         BFD_SEND (abfd, _bfd_debug_info_accumulate, (abfd, section))
 407
 408 #define bfd_stat_arch_elt(abfd, stat) \
 409         BFD_SEND (abfd, _bfd_stat_arch_elt,(abfd, stat))
 410
 411 #define bfd_coff_swap_aux_in(a,e,t,c,i) \
 412         BFD_SEND (a, _bfd_coff_swap_aux_in, (a,e,t,c,i))
 413
 414 #define bfd_coff_swap_sym_in(a,e,i) \
 415         BFD_SEND (a, _bfd_coff_swap_sym_in, (a,e,i))
 416
 417 #define bfd_coff_swap_lineno_in(a,e,i) \
 418         BFD_SEND ( a, _bfd_coff_swap_lineno_in, (a,e,i))
 419
 420 #define bfd_set_arch_mach(abfd, arch, mach)\
 421         BFD_SEND ( abfd, _bfd_set_arch_mach, (abfd, arch, mach))
 422
 423 #define bfd_coff_swap_reloc_out(abfd, i, o) \
 424         BFD_SEND (abfd, _bfd_coff_swap_reloc_out, (abfd, i, o))
 425
 426 #define bfd_coff_swap_lineno_out(abfd, i, o) \
 427         BFD_SEND (abfd, _bfd_coff_swap_lineno_out, (abfd, i, o))
 428
 429 #define bfd_coff_swap_aux_out(abfd, i, t,c,o) \
 430         BFD_SEND (abfd, _bfd_coff_swap_aux_out, (abfd, i,t,c, o))
 431
 432 #define bfd_coff_swap_sym_out(abfd, i,o) \
 433         BFD_SEND (abfd, _bfd_coff_swap_sym_out, (abfd, i, o))
 434
 435 #define bfd_coff_swap_scnhdr_out(abfd, i,o) \
 436         BFD_SEND (abfd, _bfd_coff_swap_scnhdr_out, (abfd, i, o))
 437
 438 #define bfd_coff_swap_filehdr_out(abfd, i,o) \
 439         BFD_SEND (abfd, _bfd_coff_swap_filehdr_out, (abfd, i, o))
 440
 441 #define bfd_coff_swap_aouthdr_out(abfd, i,o) \
 442         BFD_SEND (abfd, _bfd_coff_swap_aouthdr_out, (abfd, i, o))
 443
 444 *-
 445
 446 */
 447
 448
 449
 450
 451
 452