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 CONST 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 DEFUN(bfd_canonicalize_reloc,(abfd, asect, location, symbols),
 283      bfd *abfd AND
 284      sec_ptr asect AND
 285      arelent **location AND
 286      asymbol **symbols)
 287 {
 288     if (abfd->format != bfd_object) {
 289         bfd_error = invalid_operation;
 290         return 0;
 291     }
 292     return BFD_SEND (abfd, _bfd_canonicalize_reloc, (abfd, asect, location, symbols));
 293 }
 294
 295
 296 boolean
 297 bfd_set_file_flags (abfd, flags)
 298      bfd *abfd;
 299      flagword flags;
 300 {
 301   if (abfd->format != bfd_object) {
 302     bfd_error = wrong_format;
 303     return false;
 304   }
 305
 306   if (bfd_read_p (abfd)) {
 307     bfd_error = invalid_operation;
 308     return false;
 309   }
 310
 311   if ((flags & bfd_applicable_file_flags (abfd)) != flags) {
 312     bfd_error = invalid_operation;
 313     return false;
 314   }
 315
 316   bfd_get_file_flags (abfd) = flags;
 317 return true;
 318 }
 319
 320
 321 void
 322 bfd_set_reloc (ignore_abfd, asect, location, count)
 323      bfd *ignore_abfd;
 324      sec_ptr asect;
 325      arelent **location;
 326      unsigned int count;
 327 {
 328   asect->orelocation  = location;
 329   asect->reloc_count = count;
 330 }
 331
 332 void
 333 bfd_assert(file, line)
 334 char *file;
 335 int line;
 336 {
 337   printf("bfd assertion fail %s:%d\n",file,line);
 338 }
 339
 340
 341 /*proto* bfd_set_start_address
 342
 343 Marks the entry point of an output BFD. Returns @code{true} on
 344 success, @code{false} otherwise.
 345
 346 *; PROTO(boolean, bfd_set_start_address,(bfd *, bfd_vma));
 347 */
 348
 349 boolean
 350 bfd_set_start_address(abfd, vma)
 351 bfd *abfd;
 352 bfd_vma vma;
 353 {
 354   abfd->start_address = vma;
 355   return true;
 356 }
 357
 358
 359 /*proto*  bfd_get_mtime
 360
 361 Return cached file modification time (e.g. as read from archive header
 362 for archive members, or from file system if we have been called
 363 before); else determine modify time, cache it, and return it.
 364
 365 *; PROTO(long, bfd_get_mtime, (bfd *));
 366
 367 */
 368
 369 long
 370 bfd_get_mtime (abfd)
 371      bfd *abfd;
 372 {
 373   FILE *fp;
 374   struct stat buf;
 375
 376   if (abfd->mtime_set)
 377     return abfd->mtime;
 378
 379   fp = bfd_cache_lookup (abfd);
 380   if (0 != fstat (fileno (fp), &buf))
 381     return 0;
 382
 383   abfd->mtime_set = true;
 384   abfd->mtime = buf.st_mtime;
 385   return abfd->mtime;
 386 }
 387
 388 /*proto* stuff
 389
 390 *+
 391
 392 #define bfd_sizeof_headers(abfd, reloc) \
 393      BFD_SEND (abfd, _bfd_sizeof_headers, (abfd, reloc))
 394
 395 #define bfd_find_nearest_line(abfd, section, symbols, offset, filename_ptr, func, line_ptr) \
 396      BFD_SEND (abfd, _bfd_find_nearest_line,  (abfd, section, symbols, offset, filename_ptr, func, line_ptr))
 397
 398 #define bfd_debug_info_start(abfd) \
 399         BFD_SEND (abfd, _bfd_debug_info_start, (abfd))
 400
 401 #define bfd_debug_info_end(abfd) \
 402         BFD_SEND (abfd, _bfd_debug_info_end, (abfd))
 403
 404 #define bfd_debug_info_accumulate(abfd, section) \
 405         BFD_SEND (abfd, _bfd_debug_info_accumulate, (abfd, section))
 406
 407 #define bfd_stat_arch_elt(abfd, stat) \
 408         BFD_SEND (abfd, _bfd_stat_arch_elt,(abfd, stat))
 409
 410 #define bfd_coff_swap_aux_in(a,e,t,c,i) \
 411         BFD_SEND (a, _bfd_coff_swap_aux_in, (a,e,t,c,i))
 412
 413 #define bfd_coff_swap_sym_in(a,e,i) \
 414         BFD_SEND (a, _bfd_coff_swap_sym_in, (a,e,i))
 415
 416 #define bfd_coff_swap_lineno_in(a,e,i) \
 417         BFD_SEND ( a, _bfd_coff_swap_lineno_in, (a,e,i))
 418
 419 #define bfd_set_arch_mach(abfd, arch, mach)\
 420         BFD_SEND ( abfd, _bfd_set_arch_mach, (abfd, arch, mach))
 421
 422 #define bfd_coff_swap_reloc_out(abfd, i, o) \
 423         BFD_SEND (abfd, _bfd_coff_swap_reloc_out, (abfd, i, o))
 424
 425 #define bfd_coff_swap_lineno_out(abfd, i, o) \
 426         BFD_SEND (abfd, _bfd_coff_swap_lineno_out, (abfd, i, o))
 427
 428 #define bfd_coff_swap_aux_out(abfd, i, t,c,o) \
 429         BFD_SEND (abfd, _bfd_coff_swap_aux_out, (abfd, i,t,c, o))
 430
 431 #define bfd_coff_swap_sym_out(abfd, i,o) \
 432         BFD_SEND (abfd, _bfd_coff_swap_sym_out, (abfd, i, o))
 433
 434 #define bfd_coff_swap_scnhdr_out(abfd, i,o) \
 435         BFD_SEND (abfd, _bfd_coff_swap_scnhdr_out, (abfd, i, o))
 436
 437 #define bfd_coff_swap_filehdr_out(abfd, i,o) \
 438         BFD_SEND (abfd, _bfd_coff_swap_filehdr_out, (abfd, i, o))
 439
 440 #define bfd_coff_swap_aouthdr_out(abfd, i,o) \
 441         BFD_SEND (abfd, _bfd_coff_swap_aouthdr_out, (abfd, i, o))
 442
 443 *-
 444
 445 */
 446
 447
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 451