bfd/libbfd.c

   1 /* Assorted BFD support routines, only used internally.
   2    Copyright 1990, 91, 92, 93, 94, 95, 96, 97, 1998
   3    Free Software Foundation, Inc.
   4    Written by Cygnus Support.
   5
   6 This file is part of BFD, the Binary File Descriptor library.
   7
   8 This program is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 2 of the License, or
  11 (at your option) any later version.
  12
  13 This program is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with this program; if not, write to the Free Software
  20 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  21
  22 #include "bfd.h"
  23 #include "sysdep.h"
  24 #include "libbfd.h"
  25
  26 #ifndef HAVE_GETPAGESIZE
  27 #define getpagesize() 2048
  28 #endif
  29
  30 static int real_read PARAMS ((PTR, size_t, size_t, FILE *));
  31
  32 /*
  33 SECTION
  34         Internal functions
  35
  36 DESCRIPTION
  37         These routines are used within BFD.
  38         They are not intended for export, but are documented here for
  39         completeness.
  40 */
  41
  42 /* A routine which is used in target vectors for unsupported
  43    operations.  */
  44
  45 /*ARGSUSED*/
  46 boolean
  47 bfd_false (ignore)
  48      bfd *ignore;
  49 {
  50   bfd_set_error (bfd_error_invalid_operation);
  51   return false;
  52 }
  53
  54 /* A routine which is used in target vectors for supported operations
  55    which do not actually do anything.  */
  56
  57 /*ARGSUSED*/
  58 boolean
  59 bfd_true (ignore)
  60      bfd *ignore;
  61 {
  62   return true;
  63 }
  64
  65 /* A routine which is used in target vectors for unsupported
  66    operations which return a pointer value.  */
  67
  68 /*ARGSUSED*/
  69 PTR
  70 bfd_nullvoidptr (ignore)
  71      bfd *ignore;
  72 {
  73   bfd_set_error (bfd_error_invalid_operation);
  74   return NULL;
  75 }
  76
  77 /*ARGSUSED*/
  78 int
  79 bfd_0 (ignore)
  80      bfd *ignore;
  81 {
  82   return 0;
  83 }
  84
  85 /*ARGSUSED*/
  86 unsigned int
  87 bfd_0u (ignore)
  88      bfd *ignore;
  89 {
  90    return 0;
  91 }
  92
  93 /*ARGUSED*/
  94 long
  95 bfd_0l (ignore)
  96      bfd *ignore;
  97 {
  98   return 0;
  99 }
 100
 101 /* A routine which is used in target vectors for unsupported
 102    operations which return -1 on error.  */
 103
 104 /*ARGSUSED*/
 105 long
 106 _bfd_n1 (ignore_abfd)
 107      bfd *ignore_abfd;
 108 {
 109   bfd_set_error (bfd_error_invalid_operation);
 110   return -1;
 111 }
 112
 113 /*ARGSUSED*/
 114 void
 115 bfd_void (ignore)
 116      bfd *ignore;
 117 {
 118 }
 119
 120 /*ARGSUSED*/
 121 boolean
 122 _bfd_nocore_core_file_matches_executable_p (ignore_core_bfd, ignore_exec_bfd)
 123      bfd *ignore_core_bfd;
 124      bfd *ignore_exec_bfd;
 125 {
 126   bfd_set_error (bfd_error_invalid_operation);
 127   return false;
 128 }
 129
 130 /* Routine to handle core_file_failing_command entry point for targets
 131    without core file support.  */
 132
 133 /*ARGSUSED*/
 134 char *
 135 _bfd_nocore_core_file_failing_command (ignore_abfd)
 136      bfd *ignore_abfd;
 137 {
 138   bfd_set_error (bfd_error_invalid_operation);
 139   return (char *)NULL;
 140 }
 141
 142 /* Routine to handle core_file_failing_signal entry point for targets
 143    without core file support.  */
 144
 145 /*ARGSUSED*/
 146 int
 147 _bfd_nocore_core_file_failing_signal (ignore_abfd)
 148      bfd *ignore_abfd;
 149 {
 150   bfd_set_error (bfd_error_invalid_operation);
 151   return 0;
 152 }
 153
 154 /*ARGSUSED*/
 155 const bfd_target *
 156 _bfd_dummy_target (ignore_abfd)
 157      bfd *ignore_abfd;
 158 {
 159   bfd_set_error (bfd_error_wrong_format);
 160   return 0;
 161 }
 162 \f
 163 /* Allocate memory using malloc.  */
 164
 165 PTR
 166 bfd_malloc (size)
 167      size_t size;
 168 {
 169   PTR ptr;
 170
 171   ptr = (PTR) malloc (size);
 172   if (ptr == NULL && size != 0)
 173     bfd_set_error (bfd_error_no_memory);
 174   return ptr;
 175 }
 176
 177 /* Reallocate memory using realloc.  */
 178
 179 PTR
 180 bfd_realloc (ptr, size)
 181      PTR ptr;
 182      size_t size;
 183 {
 184   PTR ret;
 185
 186   if (ptr == NULL)
 187     ret = malloc (size);
 188   else
 189     ret = realloc (ptr, size);
 190
 191   if (ret == NULL)
 192     bfd_set_error (bfd_error_no_memory);
 193
 194   return ret;
 195 }
 196
 197 /* Allocate memory using malloc and clear it.  */
 198
 199 PTR
 200 bfd_zmalloc (size)
 201      size_t size;
 202 {
 203   PTR ptr;
 204
 205   ptr = (PTR) malloc (size);
 206
 207   if (size != 0)
 208     {
 209       if (ptr == NULL)
 210         bfd_set_error (bfd_error_no_memory);
 211       else
 212         memset (ptr, 0, size);
 213     }
 214
 215   return ptr;
 216 }
 217 \f
 218 /* Some IO code */
 219
 220
 221 /* Note that archive entries don't have streams; they share their parent's.
 222    This allows someone to play with the iostream behind BFD's back.
 223
 224    Also, note that the origin pointer points to the beginning of a file's
 225    contents (0 for non-archive elements).  For archive entries this is the
 226    first octet in the file, NOT the beginning of the archive header. */
 227
 228 static int
 229 real_read (where, a,b, file)
 230      PTR where;
 231      size_t a;
 232      size_t b;
 233      FILE *file;
 234 {
 235   /* FIXME - this looks like an optimization, but it's really to cover
 236      up for a feature of some OSs (not solaris - sigh) that
 237      ld/pe-dll.c takes advantage of (apparently) when it creates BFDs
 238      internally and tries to link against them.  BFD seems to be smart
 239      enough to realize there are no symbol records in the "file" that
 240      doesn't exist but attempts to read them anyway.  On Solaris,
 241      attempting to read zero bytes from a NULL file results in a core
 242      dump, but on other platforms it just returns zero bytes read.
 243      This makes it to something reasonable. - DJ */
 244   if (a == 0 || b == 0)
 245     return 0;
 246
 247 #if defined (__VAX) && defined (VMS)
 248   /* Apparently fread on Vax VMS does not keep the record length
 249      information.  */
 250   return read (fileno (file), where, a * b);
 251 #else
 252   return fread (where, a, b, file);
 253 #endif
 254 }
 255
 256 /* Return value is amount read (FIXME: how are errors and end of file dealt
 257    with?  We never call bfd_set_error, which is probably a mistake).  */
 258
 259 bfd_size_type
 260 bfd_read (ptr, size, nitems, abfd)
 261      PTR ptr;
 262      bfd_size_type size;
 263      bfd_size_type nitems;
 264      bfd *abfd;
 265 {
 266   int nread;
 267
 268   if ((abfd->flags & BFD_IN_MEMORY) != 0)
 269     {
 270       struct bfd_in_memory *bim;
 271       bfd_size_type get;
 272
 273       bim = (struct bfd_in_memory *) abfd->iostream;
 274       get = size * nitems;
 275       if (abfd->where + get > bim->size)
 276         {
 277           get = bim->size - abfd->where;
 278           bfd_set_error (bfd_error_file_truncated);
 279         }
 280       memcpy (ptr, bim->buffer + abfd->where, get);
 281       abfd->where += get;
 282       return get;
 283     }
 284
 285   nread = real_read (ptr, 1, (size_t)(size*nitems), bfd_cache_lookup(abfd));
 286   if (nread > 0)
 287     abfd->where += nread;
 288
 289   /* Set bfd_error if we did not read as much data as we expected.
 290
 291      If the read failed due to an error set the bfd_error_system_call,
 292      else set bfd_error_file_truncated.
 293
 294      A BFD backend may wish to override bfd_error_file_truncated to
 295      provide something more useful (eg. no_symbols or wrong_format).  */
 296   if (nread < (int)(size * nitems))
 297     {
 298       if (ferror (bfd_cache_lookup (abfd)))
 299         bfd_set_error (bfd_error_system_call);
 300       else
 301         bfd_set_error (bfd_error_file_truncated);
 302     }
 303
 304   return nread;
 305 }
 306
 307 /* The window support stuff should probably be broken out into
 308    another file....  */
 309 /* The idea behind the next and refcount fields is that one mapped
 310    region can suffice for multiple read-only windows or multiple
 311    non-overlapping read-write windows.  It's not implemented yet
 312    though.  */
 313 struct _bfd_window_internal {
 314   struct _bfd_window_internal *next;
 315   PTR data;
 316   bfd_size_type size;
 317   int refcount : 31;            /* should be enough... */
 318   unsigned mapped : 1;          /* 1 = mmap, 0 = malloc */
 319 };
 320
 321 void
 322 bfd_init_window (windowp)
 323      bfd_window *windowp;
 324 {
 325   windowp->data = 0;
 326   windowp->i = 0;
 327   windowp->size = 0;
 328 }
 329 \f
 330 /* Currently, if USE_MMAP is undefined, none if the window stuff is
 331    used.  Okay, so it's mis-named.  At least the command-line option
 332    "--without-mmap" is more obvious than "--without-windows" or some
 333    such.  */
 334 #ifdef USE_MMAP
 335
 336 #undef HAVE_MPROTECT /* code's not tested yet */
 337
 338 #if HAVE_MMAP || HAVE_MPROTECT || HAVE_MADVISE
 339 #include <sys/mman.h>
 340 #endif
 341
 342 #ifndef MAP_FILE
 343 #define MAP_FILE 0
 344 #endif
 345
 346 static int debug_windows;
 347
 348 void
 349 bfd_free_window (windowp)
 350      bfd_window *windowp;
 351 {
 352   bfd_window_internal *i = windowp->i;
 353   windowp->i = 0;
 354   windowp->data = 0;
 355   if (i == 0)
 356     return;
 357   i->refcount--;
 358   if (debug_windows)
 359     fprintf (stderr, "freeing window @%p<%p,%lx,%p>\n",
 360              windowp, windowp->data, windowp->size, windowp->i);
 361   if (i->refcount != 0)
 362     return;
 363
 364   if (i->mapped)
 365     {
 366 #ifdef HAVE_MMAP
 367       munmap (i->data, i->size);
 368       goto no_free;
 369 #else
 370       abort ();
 371 #endif
 372     }
 373 #ifdef HAVE_MPROTECT
 374   mprotect (i->data, i->size, PROT_READ | PROT_WRITE);
 375 #endif
 376   free (i->data);
 377 #ifdef HAVE_MMAP
 378  no_free:
 379 #endif
 380   i->data = 0;
 381   /* There should be no more references to i at this point.  */
 382   free (i);
 383 }
 384
 385 static int ok_to_map = 1;
 386
 387 boolean
 388 bfd_get_file_window (abfd, offset, size, windowp, writable)
 389      bfd *abfd;
 390      file_ptr offset;
 391      bfd_size_type size;
 392      bfd_window *windowp;
 393      boolean writable;
 394 {
 395   static size_t pagesize;
 396   bfd_window_internal *i = windowp->i;
 397   size_t size_to_alloc = size;
 398
 399   if (debug_windows)
 400     fprintf (stderr, "bfd_get_file_window (%p, %6ld, %6ld, %p<%p,%lx,%p>, %d)",
 401              abfd, (long) offset, (long) size,
 402              windowp, windowp->data, (unsigned long) windowp->size,
 403              windowp->i, writable);
 404
 405   /* Make sure we know the page size, so we can be friendly to mmap.  */
 406   if (pagesize == 0)
 407     pagesize = getpagesize ();
 408   if (pagesize == 0)
 409     abort ();
 410
 411   if (i == 0)
 412     {
 413       windowp->i = i = (bfd_window_internal *) bfd_zmalloc (sizeof (bfd_window_internal));
 414       if (i == 0)
 415         return false;
 416       i->data = 0;
 417     }
 418 #ifdef HAVE_MMAP
 419   if (ok_to_map
 420       && (i->data == 0 || i->mapped == 1)
 421       && (abfd->flags & BFD_IN_MEMORY) == 0)
 422     {
 423       file_ptr file_offset, offset2;
 424       size_t real_size;
 425       int fd;
 426       FILE *f;
 427
 428       /* Find the real file and the real offset into it.  */
 429       while (abfd->my_archive != NULL)
 430         {
 431           offset += abfd->origin;
 432           abfd = abfd->my_archive;
 433         }
 434       f = bfd_cache_lookup (abfd);
 435       fd = fileno (f);
 436
 437       /* Compute offsets and size for mmap and for the user's data.  */
 438       offset2 = offset % pagesize;
 439       if (offset2 < 0)
 440         abort ();
 441       file_offset = offset - offset2;
 442       real_size = offset + size - file_offset;
 443       real_size = real_size + pagesize - 1;
 444       real_size -= real_size % pagesize;
 445
 446       /* If we're re-using a memory region, make sure it's big enough.  */
 447       if (i->data && i->size < size)
 448         {
 449           munmap (i->data, i->size);
 450           i->data = 0;
 451         }
 452       i->data = mmap (i->data, real_size,
 453                       writable ? PROT_WRITE | PROT_READ : PROT_READ,
 454                       (writable
 455                        ? MAP_FILE | MAP_PRIVATE
 456                        : MAP_FILE | MAP_SHARED),
 457                       fd, file_offset);
 458       if (i->data == (PTR) -1)
 459         {
 460           /* An error happened.  Report it, or try using malloc, or
 461              something.  */
 462           bfd_set_error (bfd_error_system_call);
 463           i->data = 0;
 464           windowp->data = 0;
 465           if (debug_windows)
 466             fprintf (stderr, "\t\tmmap failed!\n");
 467           return false;
 468         }
 469       if (debug_windows)
 470         fprintf (stderr, "\n\tmapped %ld at %p, offset is %ld\n",
 471                  (long) real_size, i->data, (long) offset2);
 472       i->size = real_size;
 473       windowp->data = (PTR) ((bfd_byte *) i->data + offset2);
 474       windowp->size = size;
 475       i->mapped = 1;
 476       return true;
 477     }
 478   else if (debug_windows)
 479     {
 480       if (ok_to_map)
 481         fprintf (stderr, _("not mapping: data=%lx mapped=%d\n"),
 482                  (unsigned long) i->data, (int) i->mapped);
 483       else
 484         fprintf (stderr, _("not mapping: env var not set\n"));
 485     }
 486 #else
 487   ok_to_map = 0;
 488 #endif
 489
 490 #ifdef HAVE_MPROTECT
 491   if (!writable)
 492     {
 493       size_to_alloc += pagesize - 1;
 494       size_to_alloc -= size_to_alloc % pagesize;
 495     }
 496 #endif
 497   if (debug_windows)
 498     fprintf (stderr, "\n\t%s(%6ld)",
 499              i->data ? "realloc" : " malloc", (long) size_to_alloc);
 500   i->data = (PTR) bfd_realloc (i->data, size_to_alloc);
 501   if (debug_windows)
 502     fprintf (stderr, "\t-> %p\n", i->data);
 503   i->refcount = 1;
 504   if (i->data == NULL)
 505     {
 506       if (size_to_alloc == 0)
 507         return true;
 508       bfd_set_error (bfd_error_no_memory);
 509       return false;
 510     }
 511   if (bfd_seek (abfd, offset, SEEK_SET) != 0)
 512     return false;
 513   i->size = bfd_read (i->data, size, 1, abfd);
 514   if (i->size != size)
 515     return false;
 516   i->mapped = 0;
 517 #ifdef HAVE_MPROTECT
 518   if (!writable)
 519     {
 520       if (debug_windows)
 521         fprintf (stderr, "\tmprotect (%p, %ld, PROT_READ)\n", i->data,
 522                  (long) i->size);
 523       mprotect (i->data, i->size, PROT_READ);
 524     }
 525 #endif
 526   windowp->data = i->data;
 527   windowp->size = i->size;
 528   return true;
 529 }
 530
 531 #endif /* USE_MMAP */
 532 \f
 533 bfd_size_type
 534 bfd_write (ptr, size, nitems, abfd)
 535      CONST PTR ptr;
 536      bfd_size_type size;
 537      bfd_size_type nitems;
 538      bfd *abfd;
 539 {
 540   long nwrote;
 541
 542   if ((abfd->flags & BFD_IN_MEMORY) != 0)
 543     {
 544       struct bfd_in_memory *bim = (struct bfd_in_memory *) (abfd->iostream);
 545       size *= nitems;
 546       if (abfd->where + size > bim->size)
 547         {
 548           long newsize, oldsize = (bim->size + 127) & ~127;
 549           bim->size = abfd->where + size;
 550           /* Round up to cut down on memory fragmentation */
 551           newsize = (bim->size + 127) & ~127;
 552           if (newsize > oldsize)
 553             {
 554               bim->buffer = bfd_realloc (bim->buffer, newsize);
 555               if (bim->buffer == 0)
 556                 {
 557                   bim->size = 0;
 558                   return 0;
 559                 }
 560             }
 561         }
 562       memcpy (bim->buffer + abfd->where, ptr, size);
 563       abfd->where += size;
 564       return size;
 565     }
 566
 567   nwrote = fwrite (ptr, 1, (size_t) (size * nitems),
 568                    bfd_cache_lookup (abfd));
 569   if (nwrote > 0)
 570     abfd->where += nwrote;
 571   if ((bfd_size_type) nwrote != size * nitems)
 572     {
 573 #ifdef ENOSPC
 574       if (nwrote >= 0)
 575         errno = ENOSPC;
 576 #endif
 577       bfd_set_error (bfd_error_system_call);
 578     }
 579   return nwrote;
 580 }
 581
 582 /*
 583 INTERNAL_FUNCTION
 584         bfd_write_bigendian_4byte_int
 585
 586 SYNOPSIS
 587         void bfd_write_bigendian_4byte_int(bfd *abfd,  int i);
 588
 589 DESCRIPTION
 590         Write a 4 byte integer @var{i} to the output BFD @var{abfd}, in big
 591         endian order regardless of what else is going on.  This is useful in
 592         archives.
 593
 594 */
 595 void
 596 bfd_write_bigendian_4byte_int (abfd, i)
 597      bfd *abfd;
 598      int i;
 599 {
 600   bfd_byte buffer[4];
 601   bfd_putb32(i, buffer);
 602   if (bfd_write((PTR)buffer, 4, 1, abfd) != 4)
 603     abort ();
 604 }
 605
 606 long
 607 bfd_tell (abfd)
 608      bfd *abfd;
 609 {
 610   file_ptr ptr;
 611
 612   if ((abfd->flags & BFD_IN_MEMORY) != 0)
 613     return abfd->where;
 614
 615   ptr = ftell (bfd_cache_lookup(abfd));
 616
 617   if (abfd->my_archive)
 618     ptr -= abfd->origin;
 619   abfd->where = ptr;
 620   return ptr;
 621 }
 622
 623 int
 624 bfd_flush (abfd)
 625      bfd *abfd;
 626 {
 627   if ((abfd->flags & BFD_IN_MEMORY) != 0)
 628     return 0;
 629   return fflush (bfd_cache_lookup(abfd));
 630 }
 631
 632 /* Returns 0 for success, negative value for failure (in which case
 633    bfd_get_error can retrieve the error code).  */
 634 int
 635 bfd_stat (abfd, statbuf)
 636      bfd *abfd;
 637      struct stat *statbuf;
 638 {
 639   FILE *f;
 640   int result;
 641
 642   if ((abfd->flags & BFD_IN_MEMORY) != 0)
 643     abort ();
 644
 645   f = bfd_cache_lookup (abfd);
 646   if (f == NULL)
 647     {
 648       bfd_set_error (bfd_error_system_call);
 649       return -1;
 650     }
 651   result = fstat (fileno (f), statbuf);
 652   if (result < 0)
 653     bfd_set_error (bfd_error_system_call);
 654   return result;
 655 }
 656
 657 /* Returns 0 for success, nonzero for failure (in which case bfd_get_error
 658    can retrieve the error code).  */
 659
 660 int
 661 bfd_seek (abfd, position, direction)
 662      bfd *abfd;
 663      file_ptr position;
 664      int direction;
 665 {
 666   int result;
 667   FILE *f;
 668   file_ptr file_position;
 669   /* For the time being, a BFD may not seek to it's end.  The problem
 670      is that we don't easily have a way to recognize the end of an
 671      element in an archive. */
 672
 673   BFD_ASSERT (direction == SEEK_SET || direction == SEEK_CUR);
 674
 675   if (direction == SEEK_CUR && position == 0)
 676     return 0;
 677
 678   if ((abfd->flags & BFD_IN_MEMORY) != 0)
 679     {
 680       if (direction == SEEK_SET)
 681         abfd->where = position;
 682       else
 683         abfd->where += position;
 684       return 0;
 685     }
 686
 687   if (abfd->format != bfd_archive && abfd->my_archive == 0)
 688     {
 689 #if 0
 690       /* Explanation for this code: I'm only about 95+% sure that the above
 691          conditions are sufficient and that all i/o calls are properly
 692          adjusting the `where' field.  So this is sort of an `assert'
 693          that the `where' field is correct.  If we can go a while without
 694          tripping the abort, we can probably safely disable this code,
 695          so that the real optimizations happen.  */
 696       file_ptr where_am_i_now;
 697       where_am_i_now = ftell (bfd_cache_lookup (abfd));
 698       if (abfd->my_archive)
 699         where_am_i_now -= abfd->origin;
 700       if (where_am_i_now != abfd->where)
 701         abort ();
 702 #endif
 703       if (direction == SEEK_SET && position == abfd->where)
 704         return 0;
 705     }
 706   else
 707     {
 708       /* We need something smarter to optimize access to archives.
 709          Currently, anything inside an archive is read via the file
 710          handle for the archive.  Which means that a bfd_seek on one
 711          component affects the `current position' in the archive, as
 712          well as in any other component.
 713
 714          It might be sufficient to put a spike through the cache
 715          abstraction, and look to the archive for the file position,
 716          but I think we should try for something cleaner.
 717
 718          In the meantime, no optimization for archives.  */
 719     }
 720
 721   f = bfd_cache_lookup (abfd);
 722   file_position = position;
 723   if (direction == SEEK_SET && abfd->my_archive != NULL)
 724     file_position += abfd->origin;
 725
 726   result = fseek (f, file_position, direction);
 727
 728   if (result != 0)
 729     {
 730       int hold_errno = errno;
 731
 732       /* Force redetermination of `where' field.  */
 733       bfd_tell (abfd);
 734
 735       /* An EINVAL error probably means that the file offset was
 736          absurd.  */
 737       if (hold_errno == EINVAL)
 738         bfd_set_error (bfd_error_file_truncated);
 739       else
 740         {
 741           bfd_set_error (bfd_error_system_call);
 742           errno = hold_errno;
 743         }
 744     }
 745   else
 746     {
 747       /* Adjust `where' field.  */
 748       if (direction == SEEK_SET)
 749         abfd->where = position;
 750       else
 751         abfd->where += position;
 752     }
 753   return result;
 754 }
 755 \f
 756 /** The do-it-yourself (byte) sex-change kit */
 757
 758 /* The middle letter e.g. get<b>short indicates Big or Little endian
 759    target machine.  It doesn't matter what the byte order of the host
 760    machine is; these routines work for either.  */
 761
 762 /* FIXME: Should these take a count argument?
 763    Answer (gnu@cygnus.com):  No, but perhaps they should be inline
 764                              functions in swap.h #ifdef __GNUC__.
 765                              Gprof them later and find out.  */
 766
 767 /*
 768 FUNCTION
 769         bfd_put_size
 770 FUNCTION
 771         bfd_get_size
 772
 773 DESCRIPTION
 774         These macros as used for reading and writing raw data in
 775         sections; each access (except for bytes) is vectored through
 776         the target format of the BFD and mangled accordingly. The
 777         mangling performs any necessary endian translations and
 778         removes alignment restrictions.  Note that types accepted and
 779         returned by these macros are identical so they can be swapped
 780         around in macros---for example, @file{libaout.h} defines <<GET_WORD>>
 781         to either <<bfd_get_32>> or <<bfd_get_64>>.
 782
 783         In the put routines, @var{val} must be a <<bfd_vma>>.  If we are on a
 784         system without prototypes, the caller is responsible for making
 785         sure that is true, with a cast if necessary.  We don't cast
 786         them in the macro definitions because that would prevent <<lint>>
 787         or <<gcc -Wall>> from detecting sins such as passing a pointer.
 788         To detect calling these with less than a <<bfd_vma>>, use
 789         <<gcc -Wconversion>> on a host with 64 bit <<bfd_vma>>'s.
 790
 791 .
 792 .{* Byte swapping macros for user section data.  *}
 793 .
 794 .#define bfd_put_8(abfd, val, ptr) \
 795 .                (*((unsigned char *)(ptr)) = (unsigned char)(val))
 796 .#define bfd_put_signed_8 \
 797 .               bfd_put_8
 798 .#define bfd_get_8(abfd, ptr) \
 799 .                (*(unsigned char *)(ptr))
 800 .#define bfd_get_signed_8(abfd, ptr) \
 801 .               ((*(unsigned char *)(ptr) ^ 0x80) - 0x80)
 802 .
 803 .#define bfd_put_16(abfd, val, ptr) \
 804 .                BFD_SEND(abfd, bfd_putx16, ((val),(ptr)))
 805 .#define bfd_put_signed_16 \
 806 .                bfd_put_16
 807 .#define bfd_get_16(abfd, ptr) \
 808 .                BFD_SEND(abfd, bfd_getx16, (ptr))
 809 .#define bfd_get_signed_16(abfd, ptr) \
 810 .                BFD_SEND (abfd, bfd_getx_signed_16, (ptr))
 811 .
 812 .#define bfd_put_32(abfd, val, ptr) \
 813 .                BFD_SEND(abfd, bfd_putx32, ((val),(ptr)))
 814 .#define bfd_put_signed_32 \
 815 .                bfd_put_32
 816 .#define bfd_get_32(abfd, ptr) \
 817 .                BFD_SEND(abfd, bfd_getx32, (ptr))
 818 .#define bfd_get_signed_32(abfd, ptr) \
 819 .                BFD_SEND(abfd, bfd_getx_signed_32, (ptr))
 820 .
 821 .#define bfd_put_64(abfd, val, ptr) \
 822 .                BFD_SEND(abfd, bfd_putx64, ((val), (ptr)))
 823 .#define bfd_put_signed_64 \
 824 .                bfd_put_64
 825 .#define bfd_get_64(abfd, ptr) \
 826 .                BFD_SEND(abfd, bfd_getx64, (ptr))
 827 .#define bfd_get_signed_64(abfd, ptr) \
 828 .                BFD_SEND(abfd, bfd_getx_signed_64, (ptr))
 829 .
 830 */
 831
 832 /*
 833 FUNCTION
 834         bfd_h_put_size
 835         bfd_h_get_size
 836
 837 DESCRIPTION
 838         These macros have the same function as their <<bfd_get_x>>
 839         bretheren, except that they are used for removing information
 840         for the header records of object files. Believe it or not,
 841         some object files keep their header records in big endian
 842         order and their data in little endian order.
 843 .
 844 .{* Byte swapping macros for file header data.  *}
 845 .
 846 .#define bfd_h_put_8(abfd, val, ptr) \
 847 .               bfd_put_8 (abfd, val, ptr)
 848 .#define bfd_h_put_signed_8(abfd, val, ptr) \
 849 .               bfd_put_8 (abfd, val, ptr)
 850 .#define bfd_h_get_8(abfd, ptr) \
 851 .               bfd_get_8 (abfd, ptr)
 852 .#define bfd_h_get_signed_8(abfd, ptr) \
 853 .               bfd_get_signed_8 (abfd, ptr)
 854 .
 855 .#define bfd_h_put_16(abfd, val, ptr) \
 856 .                BFD_SEND(abfd, bfd_h_putx16,(val,ptr))
 857 .#define bfd_h_put_signed_16 \
 858 .                bfd_h_put_16
 859 .#define bfd_h_get_16(abfd, ptr) \
 860 .                BFD_SEND(abfd, bfd_h_getx16,(ptr))
 861 .#define bfd_h_get_signed_16(abfd, ptr) \
 862 .                BFD_SEND(abfd, bfd_h_getx_signed_16, (ptr))
 863 .
 864 .#define bfd_h_put_32(abfd, val, ptr) \
 865 .                BFD_SEND(abfd, bfd_h_putx32,(val,ptr))
 866 .#define bfd_h_put_signed_32 \
 867 .                bfd_h_put_32
 868 .#define bfd_h_get_32(abfd, ptr) \
 869 .                BFD_SEND(abfd, bfd_h_getx32,(ptr))
 870 .#define bfd_h_get_signed_32(abfd, ptr) \
 871 .                BFD_SEND(abfd, bfd_h_getx_signed_32, (ptr))
 872 .
 873 .#define bfd_h_put_64(abfd, val, ptr) \
 874 .                BFD_SEND(abfd, bfd_h_putx64,(val, ptr))
 875 .#define bfd_h_put_signed_64 \
 876 .                bfd_h_put_64
 877 .#define bfd_h_get_64(abfd, ptr) \
 878 .                BFD_SEND(abfd, bfd_h_getx64,(ptr))
 879 .#define bfd_h_get_signed_64(abfd, ptr) \
 880 .                BFD_SEND(abfd, bfd_h_getx_signed_64, (ptr))
 881 .
 882 */
 883
 884 /* Sign extension to bfd_signed_vma.  */
 885 #define COERCE16(x) (((bfd_signed_vma) (x) ^ 0x8000) - 0x8000)
 886 #define COERCE32(x) \
 887   ((bfd_signed_vma) (long) (((unsigned long) (x) ^ 0x80000000) - 0x80000000))
 888 #define EIGHT_GAZILLION (((BFD_HOST_64_BIT)0x80000000) << 32)
 889 #define COERCE64(x) \
 890   (((bfd_signed_vma) (x) ^ EIGHT_GAZILLION) - EIGHT_GAZILLION)
 891
 892 bfd_vma
 893 bfd_getb16 (addr)
 894      register const bfd_byte *addr;
 895 {
 896   return (addr[0] << 8) | addr[1];
 897 }
 898
 899 bfd_vma
 900 bfd_getl16 (addr)
 901      register const bfd_byte *addr;
 902 {
 903   return (addr[1] << 8) | addr[0];
 904 }
 905
 906 bfd_signed_vma
 907 bfd_getb_signed_16 (addr)
 908      register const bfd_byte *addr;
 909 {
 910   return COERCE16((addr[0] << 8) | addr[1]);
 911 }
 912
 913 bfd_signed_vma
 914 bfd_getl_signed_16 (addr)
 915      register const bfd_byte *addr;
 916 {
 917   return COERCE16((addr[1] << 8) | addr[0]);
 918 }
 919
 920 void
 921 bfd_putb16 (data, addr)
 922      bfd_vma data;
 923      register bfd_byte *addr;
 924 {
 925   addr[0] = (bfd_byte)(data >> 8);
 926   addr[1] = (bfd_byte )data;
 927 }
 928
 929 void
 930 bfd_putl16 (data, addr)
 931      bfd_vma data;
 932      register bfd_byte *addr;
 933 {
 934   addr[0] = (bfd_byte )data;
 935   addr[1] = (bfd_byte)(data >> 8);
 936 }
 937
 938 bfd_vma
 939 bfd_getb32 (addr)
 940      register const bfd_byte *addr;
 941 {
 942   unsigned long v;
 943
 944   v = (unsigned long) addr[0] << 24;
 945   v |= (unsigned long) addr[1] << 16;
 946   v |= (unsigned long) addr[2] << 8;
 947   v |= (unsigned long) addr[3];
 948   return (bfd_vma) v;
 949 }
 950
 951 bfd_vma
 952 bfd_getl32 (addr)
 953      register const bfd_byte *addr;
 954 {
 955   unsigned long v;
 956
 957   v = (unsigned long) addr[0];
 958   v |= (unsigned long) addr[1] << 8;
 959   v |= (unsigned long) addr[2] << 16;
 960   v |= (unsigned long) addr[3] << 24;
 961   return (bfd_vma) v;
 962 }
 963
 964 bfd_signed_vma
 965 bfd_getb_signed_32 (addr)
 966      register const bfd_byte *addr;
 967 {
 968   unsigned long v;
 969
 970   v = (unsigned long) addr[0] << 24;
 971   v |= (unsigned long) addr[1] << 16;
 972   v |= (unsigned long) addr[2] << 8;
 973   v |= (unsigned long) addr[3];
 974   return COERCE32 (v);
 975 }
 976
 977 bfd_signed_vma
 978 bfd_getl_signed_32 (addr)
 979      register const bfd_byte *addr;
 980 {
 981   unsigned long v;
 982
 983   v = (unsigned long) addr[0];
 984   v |= (unsigned long) addr[1] << 8;
 985   v |= (unsigned long) addr[2] << 16;
 986   v |= (unsigned long) addr[3] << 24;
 987   return COERCE32 (v);
 988 }
 989
 990 bfd_vma
 991 bfd_getb64 (addr)
 992      register const bfd_byte *addr;
 993 {
 994 #ifdef BFD64
 995   bfd_vma low, high;
 996
 997   high= ((((((((addr[0]) << 8) |
 998               addr[1]) << 8) |
 999             addr[2]) << 8) |
1000           addr[3]) );
1001
1002   low = (((((((((bfd_vma)addr[4]) << 8) |
1003               addr[5]) << 8) |
1004             addr[6]) << 8) |
1005           addr[7]));
1006
1007   return high << 32 | low;
1008 #else
1009   BFD_FAIL();
1010   return 0;
1011 #endif
1012 }
1013
1014 bfd_vma
1015 bfd_getl64 (addr)
1016      register const bfd_byte *addr;
1017 {
1018 #ifdef BFD64
1019   bfd_vma low, high;
1020   high= (((((((addr[7] << 8) |
1021               addr[6]) << 8) |
1022             addr[5]) << 8) |
1023           addr[4]));
1024
1025   low = ((((((((bfd_vma)addr[3] << 8) |
1026               addr[2]) << 8) |
1027             addr[1]) << 8) |
1028           addr[0]) );
1029
1030   return high << 32 | low;
1031 #else
1032   BFD_FAIL();
1033   return 0;
1034 #endif
1035
1036 }
1037
1038 bfd_signed_vma
1039 bfd_getb_signed_64 (addr)
1040      register const bfd_byte *addr;
1041 {
1042 #ifdef BFD64
1043   bfd_vma low, high;
1044
1045   high= ((((((((addr[0]) << 8) |
1046               addr[1]) << 8) |
1047             addr[2]) << 8) |
1048           addr[3]) );
1049
1050   low = (((((((((bfd_vma)addr[4]) << 8) |
1051               addr[5]) << 8) |
1052             addr[6]) << 8) |
1053           addr[7]));
1054
1055   return COERCE64(high << 32 | low);
1056 #else
1057   BFD_FAIL();
1058   return 0;
1059 #endif
1060 }
1061
1062 bfd_signed_vma
1063 bfd_getl_signed_64 (addr)
1064      register const bfd_byte *addr;
1065 {
1066 #ifdef BFD64
1067   bfd_vma low, high;
1068   high= (((((((addr[7] << 8) |
1069               addr[6]) << 8) |
1070             addr[5]) << 8) |
1071           addr[4]));
1072
1073   low = ((((((((bfd_vma)addr[3] << 8) |
1074               addr[2]) << 8) |
1075             addr[1]) << 8) |
1076           addr[0]) );
1077
1078   return COERCE64(high << 32 | low);
1079 #else
1080   BFD_FAIL();
1081   return 0;
1082 #endif
1083 }
1084
1085 void
1086 bfd_putb32 (data, addr)
1087      bfd_vma data;
1088      register bfd_byte *addr;
1089 {
1090         addr[0] = (bfd_byte)(data >> 24);
1091         addr[1] = (bfd_byte)(data >> 16);
1092         addr[2] = (bfd_byte)(data >>  8);
1093         addr[3] = (bfd_byte)data;
1094 }
1095
1096 void
1097 bfd_putl32 (data, addr)
1098      bfd_vma data;
1099      register bfd_byte *addr;
1100 {
1101         addr[0] = (bfd_byte)data;
1102         addr[1] = (bfd_byte)(data >>  8);
1103         addr[2] = (bfd_byte)(data >> 16);
1104         addr[3] = (bfd_byte)(data >> 24);
1105 }
1106
1107 void
1108 bfd_putb64 (data, addr)
1109      bfd_vma data;
1110      register bfd_byte *addr;
1111 {
1112 #ifdef BFD64
1113   addr[0] = (bfd_byte)(data >> (7*8));
1114   addr[1] = (bfd_byte)(data >> (6*8));
1115   addr[2] = (bfd_byte)(data >> (5*8));
1116   addr[3] = (bfd_byte)(data >> (4*8));
1117   addr[4] = (bfd_byte)(data >> (3*8));
1118   addr[5] = (bfd_byte)(data >> (2*8));
1119   addr[6] = (bfd_byte)(data >> (1*8));
1120   addr[7] = (bfd_byte)(data >> (0*8));
1121 #else
1122   BFD_FAIL();
1123 #endif
1124 }
1125
1126 void
1127 bfd_putl64 (data, addr)
1128      bfd_vma data;
1129      register bfd_byte *addr;
1130 {
1131 #ifdef BFD64
1132   addr[7] = (bfd_byte)(data >> (7*8));
1133   addr[6] = (bfd_byte)(data >> (6*8));
1134   addr[5] = (bfd_byte)(data >> (5*8));
1135   addr[4] = (bfd_byte)(data >> (4*8));
1136   addr[3] = (bfd_byte)(data >> (3*8));
1137   addr[2] = (bfd_byte)(data >> (2*8));
1138   addr[1] = (bfd_byte)(data >> (1*8));
1139   addr[0] = (bfd_byte)(data >> (0*8));
1140 #else
1141   BFD_FAIL();
1142 #endif
1143 }
1144 \f
1145 /* Default implementation */
1146
1147 boolean
1148 _bfd_generic_get_section_contents (abfd, section, location, offset, count)
1149      bfd *abfd;
1150      sec_ptr section;
1151      PTR location;
1152      file_ptr offset;
1153      bfd_size_type count;
1154 {
1155     if (count == 0)
1156         return true;
1157     if ((bfd_size_type)(offset+count) > section->_raw_size
1158         || bfd_seek(abfd, (file_ptr)(section->filepos + offset), SEEK_SET) == -1
1159         || bfd_read(location, (bfd_size_type)1, count, abfd) != count)
1160         return (false); /* on error */
1161     return (true);
1162 }
1163
1164 boolean
1165 _bfd_generic_get_section_contents_in_window (abfd, section, w, offset, count)
1166      bfd *abfd;
1167      sec_ptr section;
1168      bfd_window *w;
1169      file_ptr offset;
1170      bfd_size_type count;
1171 {
1172 #ifdef USE_MMAP
1173   if (count == 0)
1174     return true;
1175   if (abfd->xvec->_bfd_get_section_contents != _bfd_generic_get_section_contents)
1176     {
1177       /* We don't know what changes the bfd's get_section_contents
1178          method may have to make.  So punt trying to map the file
1179          window, and let get_section_contents do its thing.  */
1180       /* @@ FIXME : If the internal window has a refcount of 1 and was
1181          allocated with malloc instead of mmap, just reuse it.  */
1182       bfd_free_window (w);
1183       w->i = (bfd_window_internal *) bfd_zmalloc (sizeof (bfd_window_internal));
1184       if (w->i == NULL)
1185         return false;
1186       w->i->data = (PTR) bfd_malloc ((size_t) count);
1187       if (w->i->data == NULL)
1188         {
1189           free (w->i);
1190           w->i = NULL;
1191           return false;
1192         }
1193       w->i->mapped = 0;
1194       w->i->refcount = 1;
1195       w->size = w->i->size = count;
1196       w->data = w->i->data;
1197       return bfd_get_section_contents (abfd, section, w->data, offset, count);
1198     }
1199   if ((bfd_size_type) (offset+count) > section->_raw_size
1200       || (bfd_get_file_window (abfd, section->filepos + offset, count, w, true)
1201           == false))
1202     return false;
1203   return true;
1204 #else
1205   abort ();
1206 #endif
1207 }
1208
1209 /* This generic function can only be used in implementations where creating
1210    NEW sections is disallowed.  It is useful in patching existing sections
1211    in read-write files, though.  See other set_section_contents functions
1212    to see why it doesn't work for new sections.  */
1213 boolean
1214 _bfd_generic_set_section_contents (abfd, section, location, offset, count)
1215      bfd *abfd;
1216      sec_ptr section;
1217      PTR location;
1218      file_ptr offset;
1219      bfd_size_type count;
1220 {
1221   if (count == 0)
1222     return true;
1223
1224   if (bfd_seek (abfd, (file_ptr) (section->filepos + offset), SEEK_SET) == -1
1225       || bfd_write (location, (bfd_size_type) 1, count, abfd) != count)
1226     return false;
1227
1228   return true;
1229 }
1230
1231 /*
1232 INTERNAL_FUNCTION
1233         bfd_log2
1234
1235 SYNOPSIS
1236         unsigned int bfd_log2(bfd_vma x);
1237
1238 DESCRIPTION
1239         Return the log base 2 of the value supplied, rounded up.  E.g., an
1240         @var{x} of 1025 returns 11.
1241 */
1242
1243 unsigned int
1244 bfd_log2 (x)
1245      bfd_vma x;
1246 {
1247   unsigned int result = 0;
1248
1249   while ((((bfd_vma) 1) << result) < x)
1250     ++result;
1251   return result;
1252 }
1253
1254 boolean
1255 bfd_generic_is_local_label_name (abfd, name)
1256      bfd *abfd;
1257      const char *name;
1258 {
1259   char locals_prefix = (bfd_get_symbol_leading_char (abfd) == '_') ? 'L' : '.';
1260
1261   return (name[0] == locals_prefix);
1262 }
1263
1264 /*  Can be used from / for bfd_merge_private_bfd_data to check that
1265     endianness matches between input and output file.  Returns
1266     true for a match, otherwise returns false and emits an error.  */
1267 boolean
1268 _bfd_generic_verify_endian_match (ibfd, obfd)
1269      bfd *ibfd;
1270      bfd *obfd;
1271 {
1272   if (ibfd->xvec->byteorder != obfd->xvec->byteorder
1273       && obfd->xvec->byteorder != BFD_ENDIAN_UNKNOWN)
1274     {
1275       (*_bfd_error_handler)
1276         ("%s: compiled for a %s endian system and target is %s endian",
1277          bfd_get_filename (ibfd),
1278          bfd_big_endian (ibfd) ? "big" : "little",
1279          bfd_big_endian (obfd) ? "big" : "little");
1280
1281       bfd_set_error (bfd_error_wrong_format);
1282       return false;
1283     }
1284
1285   return true;
1286 }