binutils/coffgrok.c

   1 /* coffgrok.c
   2    Copyright (C) 1994-2024 Free Software Foundation, Inc.
   3
   4    This file is part of GNU Binutils.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  19    MA 02110-1301, USA.  */
  20
  21
  22 /* Written by Steve Chamberlain (sac@cygnus.com)
  23
  24    This module reads a coff file and builds a really simple type tree
  25    which can be read by other programs.  The first application is a
  26    coff->sysroff converter.  It can be tested with coffdump.c.  */
  27
  28 #include "sysdep.h"
  29 #include "bfd.h"
  30 #include "libiberty.h"
  31 #include "coff/internal.h"
  32 #include "../bfd/libcoff.h"
  33 #include "bucomm.h"
  34 #include "coffgrok.h"
  35
  36 static int                      lofile = 1;
  37
  38 static struct coff_scope *      top_scope;
  39 static struct coff_scope *      file_scope;
  40 static struct coff_ofile *      ofile;
  41 static struct coff_symbol *     last_function_symbol;
  42 static struct coff_type *       last_function_type;
  43 static struct coff_type *       last_struct;
  44 static struct coff_type *       last_enum;
  45 static struct coff_sfile *      cur_sfile;
  46 static struct coff_symbol **    tindex;
  47 static asymbol **               syms;
  48 static long                     symcount;
  49 static struct coff_ptr_struct * rawsyms;
  50 static unsigned int             rawcount;
  51 static bfd *                    abfd;
  52
  53 #define N(x) ((x)->_n._n_nptr[1])
  54
  55 #define PTR_SIZE        4
  56 #define SHORT_SIZE      2
  57 #define INT_SIZE        4
  58 #define LONG_SIZE       4
  59 #define FLOAT_SIZE      4
  60 #define DOUBLE_SIZE     8
  61
  62 #define INDEXOF(p)  ((struct coff_ptr_struct *)(p)-(rawsyms))
  63
  64
  65 static struct coff_scope *
  66 empty_scope (void)
  67 {
  68   return (struct coff_scope *) (xcalloc (1, sizeof (struct coff_scope)));
  69 }
  70
  71 static struct coff_symbol *
  72 empty_symbol (void)
  73 {
  74   return (struct coff_symbol *) (xcalloc (1, sizeof (struct coff_symbol)));
  75 }
  76
  77 static void
  78 push_scope (int slink)
  79 {
  80   struct coff_scope *n = empty_scope ();
  81
  82   if (slink)
  83     {
  84       if (top_scope)
  85         {
  86           if (top_scope->list_tail)
  87             {
  88               top_scope->list_tail->next = n;
  89             }
  90           else
  91             {
  92               top_scope->list_head = n;
  93             }
  94           top_scope->list_tail = n;
  95         }
  96     }
  97   n->parent = top_scope;
  98
  99   top_scope = n;
 100 }
 101
 102 static void
 103 pop_scope (void)
 104 {
 105   /* PR 17512: file: 809933ac.  */
 106   if (top_scope == NULL)
 107     fatal (_("Out of context scope change encountered"));
 108   top_scope = top_scope->parent;
 109 }
 110
 111 static void
 112 do_sections_p1 (struct coff_ofile *head)
 113 {
 114   asection *section;
 115   int idx;
 116   struct coff_section *all = (struct coff_section *) (xcalloc (abfd->section_count + 1,
 117                                              sizeof (struct coff_section)));
 118   head->nsections = abfd->section_count + 1;
 119   head->sections = all;
 120
 121   for (idx = 0, section = abfd->sections; section; section = section->next, idx++)
 122     {
 123       long relsize;
 124       unsigned int i = section->target_index;
 125       arelent **relpp;
 126       long relcount;
 127
 128       /* PR 17512: file: 2d6effca.  */
 129       if (i > abfd->section_count)
 130         fatal (_("Invalid section target index: %u"), i);
 131
 132       relsize = bfd_get_reloc_upper_bound (abfd, section);
 133       if (relsize < 0)
 134         bfd_fatal (bfd_get_filename (abfd));
 135       if (relsize == 0)
 136         continue;
 137       relpp = (arelent **) xmalloc (relsize);
 138       relcount = bfd_canonicalize_reloc (abfd, section, relpp, syms);
 139       if (relcount < 0)
 140         bfd_fatal (bfd_get_filename (abfd));
 141
 142       head->sections[i].name = (char *) (section->name);
 143       head->sections[i].code = section->flags & SEC_CODE;
 144       head->sections[i].data = section->flags & SEC_DATA;
 145       if (strcmp (section->name, ".bss") == 0)
 146         head->sections[i].data = 1;
 147       head->sections[i].address = section->lma;
 148       head->sections[i].size = bfd_section_size (section);
 149       head->sections[i].number = idx;
 150       head->sections[i].nrelocs = section->reloc_count;
 151       head->sections[i].relocs =
 152         (struct coff_reloc *) (xcalloc (section->reloc_count,
 153                                         sizeof (struct coff_reloc)));
 154       head->sections[i].bfd_section = section;
 155     }
 156   head->sections[0].name = "ABSOLUTE";
 157   head->sections[0].code = 0;
 158   head->sections[0].data = 0;
 159   head->sections[0].address = 0;
 160   head->sections[0].size = 0;
 161   head->sections[0].number = 0;
 162 }
 163
 164 static void
 165 do_sections_p2 (struct coff_ofile *head)
 166 {
 167   asection *section;
 168
 169   for (section = abfd->sections; section; section = section->next)
 170     {
 171       unsigned int j;
 172
 173       /* PR 17512: file: 7c1a36e8.
 174          A corrupt COFF binary might have a reloc count but no relocs.
 175          Handle this here.  */
 176       if (section->relocation == NULL)
 177         continue;
 178
 179       for (j = 0; j < section->reloc_count; j++)
 180         {
 181           unsigned int idx;
 182           int i = section->target_index;
 183           struct coff_reloc *r;
 184           arelent *sr = section->relocation + j;
 185
 186           if (i > head->nsections)
 187             fatal (_("Invalid section target index: %d"), i);
 188           /* PR 17512: file: db850ff4.  */
 189           if (j >= head->sections[i].nrelocs)
 190             fatal (_("Target section has insufficient relocs"));
 191           r = head->sections[i].relocs + j;
 192           r->offset = sr->address;
 193           r->addend = sr->addend;
 194           idx = ((coff_symbol_type *) (sr->sym_ptr_ptr[0]))->native - rawsyms;
 195           if (idx >= rawcount)
 196             {
 197               if (rawcount == 0)
 198                 fatal (_("Symbol index %u encountered when there are no symbols"), idx);
 199               non_fatal (_("Invalid symbol index %u encountered"), idx);
 200               idx = 0;
 201             }
 202           r->symbol = tindex[idx];
 203         }
 204     }
 205 }
 206
 207 static struct coff_where *
 208 do_where (unsigned int i)
 209 {
 210   struct internal_syment *sym;
 211   struct coff_where *where =
 212     (struct coff_where *) (xmalloc (sizeof (struct coff_where)));
 213
 214   if (i >= rawcount)
 215     fatal ("Invalid symbol index: %d\n", i);
 216
 217   sym = &rawsyms[i].u.syment;
 218   where->offset = sym->n_value;
 219
 220   if (sym->n_scnum == -1)
 221     sym->n_scnum = 0;
 222
 223   switch (sym->n_sclass)
 224     {
 225     case C_FIELD:
 226       where->where = coff_where_member_of_struct;
 227       where->offset = sym->n_value / 8;
 228       where->bitoffset = sym->n_value % 8;
 229       where->bitsize = rawsyms[i + 1].u.auxent.x_sym.x_misc.x_lnsz.x_size;
 230       break;
 231     case C_MOE:
 232       where->where = coff_where_member_of_enum;
 233       break;
 234     case C_MOS:
 235     case C_MOU:
 236       where->where = coff_where_member_of_struct;
 237       break;
 238     case C_AUTO:
 239     case C_ARG:
 240       where->where = coff_where_stack;
 241       break;
 242     case C_EXT:
 243     case C_STAT:
 244     case C_EXTDEF:
 245     case C_LABEL:
 246       where->where = coff_where_memory;
 247       /* PR 17512: file: 07a37c40.  */
 248       /* PR 17512: file: 0c2eb101.  */
 249       if (sym->n_scnum >= ofile->nsections || sym->n_scnum < 0)
 250         {
 251           non_fatal (_("Invalid section number (%d) encountered"),
 252                      sym->n_scnum);
 253           where->section = ofile->sections;
 254         }
 255       else
 256         where->section = &ofile->sections[sym->n_scnum];
 257       break;
 258     case C_REG:
 259     case C_REGPARM:
 260       where->where = coff_where_register;
 261       break;
 262     case C_ENTAG:
 263       where->where = coff_where_entag;
 264       break;
 265     case C_STRTAG:
 266     case C_UNTAG:
 267       where->where = coff_where_strtag;
 268       break;
 269     case C_TPDEF:
 270       where->where = coff_where_typedef;
 271       break;
 272     default:
 273       fatal (_("Unrecognized symbol class: %d"), sym->n_sclass);
 274       break;
 275     }
 276   return where;
 277 }
 278
 279 static struct coff_line *
 280 do_lines (int i, char *name ATTRIBUTE_UNUSED)
 281 {
 282   struct coff_line *res = (struct coff_line *) xcalloc (1, sizeof (struct coff_line));
 283   asection *s;
 284   unsigned int l;
 285
 286   /* Find out if this function has any line numbers in the table.  */
 287   for (s = abfd->sections; s; s = s->next)
 288     {
 289       /* PR 17512: file: 07a37c40.
 290          A corrupt COFF binary can have a linenumber count in the header
 291          but no line number table.  This should be reported elsewhere, but
 292          do not rely upon this.  */
 293       if (s->lineno == NULL)
 294         continue;
 295
 296       for (l = 0; l < s->lineno_count; l++)
 297         {
 298           if (s->lineno[l].line_number == 0)
 299             {
 300               if (rawsyms + i == ((coff_symbol_type *) (&(s->lineno[l].u.sym[0])))->native)
 301                 {
 302                   /* These lines are for this function - so count them and stick them on.  */
 303                   int c = 0;
 304                   /* Find the linenumber of the top of the function, since coff linenumbers
 305                      are relative to the start of the function.  */
 306                   int start_line = rawsyms[i + 3].u.auxent.x_sym.x_misc.x_lnsz.x_lnno;
 307
 308                   l++;
 309                   for (c = 0;
 310                        /* PR 17512: file: c2825452.  */
 311                        l + c + 1 < s->lineno_count
 312                          && s->lineno[l + c + 1].line_number;
 313                        c++)
 314                     ;
 315
 316                   /* Add two extra records, one for the prologue and one for the epilogue.  */
 317                   c += 1;
 318                   res->nlines = c;
 319                   res->lines = (int *) (xcalloc (c, sizeof (int)));
 320                   res->addresses = (int *) (xcalloc (c, sizeof (int)));
 321                   res->lines[0] = start_line;
 322                   res->addresses[0] = rawsyms[i].u.syment.n_value - s->vma;
 323                   for (c = 0;
 324                        /* PR 17512: file: c2825452.  */
 325                        l + c + 1 < s->lineno_count
 326                          && s->lineno[l + c + 1].line_number;
 327                        c++)
 328                     {
 329                       res->lines[c + 1] = s->lineno[l + c].line_number + start_line - 1;
 330                       res->addresses[c + 1] = s->lineno[l + c].u.offset;
 331                     }
 332                   return res;
 333                 }
 334             }
 335         }
 336     }
 337   return res;
 338 }
 339
 340 static struct coff_type *
 341 do_type (unsigned int i)
 342 {
 343   struct internal_syment *sym;
 344   combined_entry_type *aux;
 345   struct coff_type *res = (struct coff_type *) xmalloc (sizeof (struct coff_type));
 346   int type;
 347   int which_dt = 0;
 348   int dimind = 0;
 349
 350   if (i >= rawcount)
 351     fatal (_("Type entry %u does not have enough symbolic information"), i);
 352
 353   if (!rawsyms[i].is_sym)
 354     fatal (_("Type entry %u does not refer to a symbol"), i);
 355   sym = &rawsyms[i].u.syment;
 356
 357   if (sym->n_numaux == 0 || i >= rawcount -1 || rawsyms[i + 1].is_sym)
 358     aux = NULL;
 359   else
 360     aux = &rawsyms[i + 1];
 361
 362   type = sym->n_type;
 363
 364   res->type = coff_basic_type;
 365   res->u.basic = type & 0xf;
 366
 367   switch (type & 0xf)
 368     {
 369     case T_NULL:
 370     case T_VOID:
 371       if (sym->n_numaux && sym->n_sclass == C_STAT)
 372         {
 373           /* This is probably a section definition.  */
 374           res->type = coff_secdef_type;
 375           if (aux == NULL)
 376             fatal (_("Section definition needs a section length"));
 377           res->size = aux->u.auxent.x_scn.x_scnlen;
 378
 379           /* PR 17512: file: 081c955d.
 380              Fill in the asecdef structure as well.  */
 381           res->u.asecdef.address = 0;
 382           res->u.asecdef.size = 0;
 383         }
 384       else
 385         {
 386           if (type == 0)
 387             {
 388               /* Don't know what this is, let's make it a simple int.  */
 389               res->size = INT_SIZE;
 390               res->u.basic = T_UINT;
 391             }
 392           else
 393             {
 394               /* Else it could be a function or pointer to void.  */
 395               res->size = 0;
 396             }
 397         }
 398       break;
 399
 400     case T_UCHAR:
 401     case T_CHAR:
 402       res->size = 1;
 403       break;
 404     case T_USHORT:
 405     case T_SHORT:
 406       res->size = SHORT_SIZE;
 407       break;
 408     case T_UINT:
 409     case T_INT:
 410       res->size = INT_SIZE;
 411       break;
 412     case T_ULONG:
 413     case T_LONG:
 414       res->size = LONG_SIZE;
 415       break;
 416     case T_FLOAT:
 417       res->size = FLOAT_SIZE;
 418       break;
 419     case T_DOUBLE:
 420       res->size = DOUBLE_SIZE;
 421       break;
 422     case T_STRUCT:
 423     case T_UNION:
 424       if (sym->n_numaux)
 425         {
 426           if (aux == NULL)
 427             fatal (_("Aggregate definition needs auxiliary information"));
 428
 429           if (aux->fix_tag)
 430             {
 431               unsigned int idx = INDEXOF (aux->u.auxent.x_sym.x_tagndx.p);
 432
 433               /* Referring to a struct defined elsewhere.  */
 434               res->type = coff_structref_type;
 435               res->u.astructref.ref = tindex[idx];
 436               res->size = res->u.astructref.ref ?
 437                 res->u.astructref.ref->type->size : 0;
 438             }
 439           else
 440             {
 441               /* A definition of a struct.  */
 442               last_struct = res;
 443               res->type = coff_structdef_type;
 444               res->u.astructdef.elements = empty_scope ();
 445               res->u.astructdef.idx = 0;
 446               res->u.astructdef.isstruct = (type & 0xf) == T_STRUCT;
 447               res->size = aux->u.auxent.x_sym.x_misc.x_lnsz.x_size;
 448             }
 449         }
 450       else
 451         {
 452           /* No auxents - it's anonymous.  */
 453           res->type = coff_structref_type;
 454           res->u.astructref.ref = 0;
 455           res->size = 0;
 456         }
 457       break;
 458     case T_ENUM:
 459       if (aux == NULL)
 460         fatal (_("Enum definition needs auxiliary information"));
 461       if (aux->fix_tag)
 462         {
 463           unsigned int idx = INDEXOF (aux->u.auxent.x_sym.x_tagndx.p);
 464
 465           /* Referring to a enum defined elsewhere.  */
 466           res->type = coff_enumref_type;
 467           res->u.aenumref.ref = tindex[idx];
 468           /* PR 17512: file: b85b67e8.  */
 469           if (res->u.aenumref.ref)
 470             res->size = res->u.aenumref.ref->type->size;
 471           else
 472             res->size = 0;
 473         }
 474       else
 475         {
 476           /* A definition of an enum.  */
 477           last_enum = res;
 478           res->type = coff_enumdef_type;
 479           res->u.aenumdef.elements = empty_scope ();
 480           res->size = aux->u.auxent.x_sym.x_misc.x_lnsz.x_size;
 481         }
 482       break;
 483     case T_MOE:
 484       break;
 485     }
 486
 487   for (which_dt = 5; which_dt >= 0; which_dt--)
 488     {
 489       switch ((type >> ((which_dt * 2) + 4)) & 0x3)
 490         {
 491         case 0:
 492           break;
 493         case DT_ARY:
 494           {
 495             struct coff_type *ptr = ((struct coff_type *)
 496                                      xmalloc (sizeof (struct coff_type)));
 497             int els;
 498
 499             if (aux == NULL)
 500               fatal (_("Array definition needs auxiliary information"));
 501             els = (dimind < DIMNUM
 502                    ? aux->u.auxent.x_sym.x_fcnary.x_ary.x_dimen[dimind]
 503                    : 0);
 504
 505             ++dimind;
 506             ptr->type = coff_array_type;
 507             /* PR 17512: file: ae1971e2.
 508                Check for integer overflow.  */
 509             {
 510               long long a, z;
 511               a = els;
 512               z = res->size;
 513               a *= z;
 514               ptr->size = (int) a;
 515               if (ptr->size != a)
 516                 non_fatal (_("Out of range sum for els (%#x) * size (%#x)"), els, res->size);
 517             }
 518             ptr->u.array.dim = els;
 519             ptr->u.array.array_of = res;
 520             res = ptr;
 521             break;
 522           }
 523         case DT_PTR:
 524           {
 525             struct coff_type *ptr =
 526               (struct coff_type *) xmalloc (sizeof (struct coff_type));
 527
 528             ptr->size = PTR_SIZE;
 529             ptr->type = coff_pointer_type;
 530             ptr->u.pointer.points_to = res;
 531             res = ptr;
 532             break;
 533           }
 534         case DT_FCN:
 535           {
 536             struct coff_type *ptr
 537               = (struct coff_type *) xmalloc (sizeof (struct coff_type));
 538
 539             ptr->size = 0;
 540             ptr->type = coff_function_type;
 541             ptr->u.function.function_returns = res;
 542             ptr->u.function.parameters = empty_scope ();
 543             ptr->u.function.lines = do_lines (i, N(sym));
 544             ptr->u.function.code = 0;
 545             last_function_type = ptr;
 546             res = ptr;
 547             break;
 548           }
 549         }
 550     }
 551   return res;
 552 }
 553
 554 static struct coff_visible *
 555 do_visible (int i)
 556 {
 557   struct internal_syment *sym = &rawsyms[i].u.syment;
 558   struct coff_visible *visible =
 559     (struct coff_visible *) (xmalloc (sizeof (struct coff_visible)));
 560   enum coff_vis_type t;
 561
 562   switch (sym->n_sclass)
 563     {
 564     case C_MOS:
 565     case C_MOU:
 566     case C_FIELD:
 567       t = coff_vis_member_of_struct;
 568       break;
 569     case C_MOE:
 570       t = coff_vis_member_of_enum;
 571       break;
 572     case C_REGPARM:
 573       t = coff_vis_regparam;
 574       break;
 575     case C_REG:
 576       t = coff_vis_register;
 577       break;
 578     case C_STRTAG:
 579     case C_UNTAG:
 580     case C_ENTAG:
 581     case C_TPDEF:
 582       t = coff_vis_tag;
 583       break;
 584     case C_AUTOARG:
 585     case C_ARG:
 586       t = coff_vis_autoparam;
 587       break;
 588     case C_AUTO:
 589       t = coff_vis_auto;
 590       break;
 591     case C_LABEL:
 592     case C_STAT:
 593       t = coff_vis_int_def;
 594       break;
 595     case C_EXT:
 596       if (sym->n_scnum == N_UNDEF)
 597         {
 598           if (sym->n_value)
 599             t = coff_vis_common;
 600           else
 601             t = coff_vis_ext_ref;
 602         }
 603       else
 604         t = coff_vis_ext_def;
 605       break;
 606     default:
 607       fatal (_("Unrecognised symbol class: %d"), sym->n_sclass);
 608       break;
 609     }
 610   visible->type = t;
 611   return visible;
 612 }
 613
 614 /* Define a symbol and attach to block B.  */
 615
 616 static int
 617 do_define (unsigned int i, struct coff_scope *b)
 618 {
 619   static int symbol_index;
 620   struct internal_syment *sym;
 621   struct coff_symbol *s = empty_symbol ();
 622
 623   if (b == NULL)
 624     fatal (_("ICE: do_define called without a block"));
 625   if (i >= rawcount)
 626     fatal (_("Out of range symbol index: %u"), i);
 627
 628   sym = &rawsyms[i].u.syment;
 629   s->number = ++symbol_index;
 630   s->name = N(sym);
 631   s->sfile = cur_sfile;
 632   /* Glue onto the ofile list.  */
 633   if (lofile >= 0)
 634     {
 635       if (ofile->symbol_list_tail)
 636         ofile->symbol_list_tail->next_in_ofile_list = s;
 637       else
 638         ofile->symbol_list_head = s;
 639       ofile->symbol_list_tail = s;
 640       /* And the block list.  */
 641     }
 642   if (b->vars_tail)
 643     b->vars_tail->next = s;
 644   else
 645     b->vars_head = s;
 646
 647   b->vars_tail = s;
 648   b->nvars++;
 649   s->type = do_type (i);
 650   s->where = do_where (i);
 651   s->visible = do_visible (i);
 652
 653   tindex[i] = s;
 654
 655   /* We remember the lowest address in each section for each source file.  */
 656   if (s->where->where == coff_where_memory
 657       && s->type->type == coff_secdef_type)
 658     {
 659       struct coff_isection *is;
 660
 661       /* PR 17512: file: 4676c97f.  */
 662       if (cur_sfile == NULL)
 663         non_fatal (_("Section referenced before any file is defined"));
 664       else
 665         {
 666           is = cur_sfile->section + s->where->section->number;
 667
 668           if (!is->init)
 669             {
 670               is->low = s->where->offset;
 671               /* PR 17512: file: 37e7a80d.
 672                  Check for integer overflow computing low + size.  */
 673               {
 674                 long long a, z;
 675
 676                 a = s->where->offset;
 677                 z = s->type->size;
 678                 a += z;
 679                 is->high = (int) a;
 680                 if (a != is->high)
 681                   non_fatal (_("Out of range sum for offset (%#x) + size (%#x)"),
 682                              is->low, s->type->size);
 683               }
 684               /* PR 17512: file: 37e7a80d.  */
 685               if (is->high < s->where->offset)
 686                 fatal (_("Out of range type size: %u"), s->type->size);
 687               is->init = 1;
 688               is->parent = s->where->section;
 689             }
 690         }
 691     }
 692
 693   if (s->type->type == coff_function_type)
 694     last_function_symbol = s;
 695
 696   return i + sym->n_numaux + 1;
 697 }
 698
 699 static struct coff_ofile *
 700 doit (void)
 701 {
 702   unsigned int i;
 703   bool infile = false;
 704   struct coff_ofile *head =
 705     (struct coff_ofile *) xmalloc (sizeof (struct coff_ofile));
 706
 707   ofile = head;
 708   head->source_head = 0;
 709   head->source_tail = 0;
 710   head->nsources = 0;
 711   head->symbol_list_tail = 0;
 712   head->symbol_list_head = 0;
 713   do_sections_p1 (head);
 714   push_scope (1);
 715
 716   for (i = 0; i < rawcount;)
 717     {
 718       struct internal_syment *sym = &rawsyms[i].u.syment;
 719
 720       switch (sym->n_sclass)
 721         {
 722         case C_FILE:
 723           {
 724             /* New source file announced.  */
 725             struct coff_sfile *n =
 726               (struct coff_sfile *) xmalloc (sizeof (struct coff_sfile));
 727
 728             n->section = (struct coff_isection *) xcalloc (abfd->section_count + 1, sizeof (struct coff_isection));
 729             cur_sfile = n;
 730             n->name = N(sym);
 731             n->next = 0;
 732
 733             if (infile)
 734               pop_scope ();
 735             else
 736               infile = true;
 737
 738             push_scope (1);
 739             file_scope = n->scope = top_scope;
 740
 741             if (head->source_tail)
 742               head->source_tail->next = n;
 743             else
 744               head->source_head = n;
 745             head->source_tail = n;
 746             head->nsources++;
 747             i += sym->n_numaux + 1;
 748           }
 749           break;
 750         case C_FCN:
 751           {
 752             char *name = N(sym);
 753
 754             if (name[1] == 'b')
 755               {
 756                 /* Function start.  */
 757                 push_scope (0);
 758                 /* PR 17512: file: 0ef7fbaf.  */
 759                 if (last_function_type)
 760                   last_function_type->u.function.code = top_scope;
 761                 /* PR 17512: file: 22908266.  */
 762                 if (sym->n_scnum < ofile->nsections && sym->n_scnum >= 0)
 763                   top_scope->sec = ofile->sections + sym->n_scnum;
 764                 else
 765                   top_scope->sec = NULL;
 766                 top_scope->offset = sym->n_value;
 767               }
 768             else
 769               {
 770                 /* PR 17512: file: e92e42e1.  */
 771                 if (top_scope == NULL)
 772                   fatal (_("Function start encountered without a top level scope."));
 773                 top_scope->size = sym->n_value - top_scope->offset + 1;
 774                 pop_scope ();
 775               }
 776             i += sym->n_numaux + 1;
 777           }
 778           break;
 779
 780         case C_BLOCK:
 781           {
 782             char *name = N(sym);
 783
 784             if (name[1] == 'b')
 785               {
 786                 /* Block start.  */
 787                 push_scope (1);
 788                 /* PR 17512: file: af7e8e83.  */
 789                 if (sym->n_scnum < ofile->nsections && sym->n_scnum >= 0)
 790                   top_scope->sec = ofile->sections + sym->n_scnum;
 791                 else
 792                   top_scope->sec = NULL;
 793                 top_scope->offset = sym->n_value;
 794               }
 795             else
 796               {
 797                 if (top_scope == NULL)
 798                   fatal (_("Block start encountered without a scope for it."));
 799                 top_scope->size = sym->n_value - top_scope->offset + 1;
 800                 pop_scope ();
 801               }
 802             i += sym->n_numaux + 1;
 803           }
 804           break;
 805         case C_REGPARM:
 806         case C_ARG:
 807           if (last_function_symbol == NULL)
 808             fatal (_("Function arguments encountered without a function definition"));
 809           i = do_define (i, last_function_symbol->type->u.function.parameters);
 810           break;
 811         case C_MOS:
 812         case C_MOU:
 813         case C_FIELD:
 814           /* PR 17512: file: 43ab21f4.  */
 815           if (last_struct == NULL)
 816             fatal (_("Structure element encountered without a structure definition"));
 817           i = do_define (i, last_struct->u.astructdef.elements);
 818           break;
 819         case C_MOE:
 820           if (last_enum == NULL)
 821             fatal (_("Enum element encountered without an enum definition"));
 822           i = do_define (i, last_enum->u.aenumdef.elements);
 823           break;
 824         case C_STRTAG:
 825         case C_ENTAG:
 826         case C_UNTAG:
 827           /* Various definition.  */
 828           if (top_scope == NULL)
 829             fatal (_("Aggregate definition encountered without a scope"));
 830           i = do_define (i, top_scope);
 831           break;
 832         case C_EXT:
 833         case C_LABEL:
 834           if (file_scope == NULL)
 835             fatal (_("Label definition encountered without a file scope"));
 836           i = do_define (i, file_scope);
 837           break;
 838         case C_STAT:
 839         case C_TPDEF:
 840         case C_AUTO:
 841         case C_REG:
 842           if (top_scope == NULL)
 843             fatal (_("Variable definition encountered without a scope"));
 844           i = do_define (i, top_scope);
 845           break;
 846         case C_EOS:
 847           i += sym->n_numaux + 1;
 848           break;
 849         default:
 850           fatal (_("Unrecognised symbol class: %d"), sym->n_sclass);
 851         }
 852     }
 853   do_sections_p2 (head);
 854   return head;
 855 }
 856
 857 struct coff_ofile *
 858 coff_grok (bfd *inabfd)
 859 {
 860   long storage;
 861   struct coff_ofile *p;
 862   abfd = inabfd;
 863
 864   if (! bfd_family_coff (abfd))
 865     {
 866       non_fatal (_("%s: is not a COFF format file"), bfd_get_filename (abfd));
 867       return NULL;
 868     }
 869
 870   storage = bfd_get_symtab_upper_bound (abfd);
 871
 872   if (storage < 0)
 873     bfd_fatal (bfd_get_filename (abfd));
 874
 875   syms = (asymbol **) xmalloc (storage);
 876   symcount = bfd_canonicalize_symtab (abfd, syms);
 877   if (symcount < 0)
 878     bfd_fatal (bfd_get_filename (abfd));
 879   rawsyms = obj_raw_syments (abfd);
 880   rawcount = obj_raw_syment_count (abfd);
 881   tindex = (struct coff_symbol **) (xcalloc (rawcount,
 882                                              sizeof (struct coff_symbol *)));
 883
 884   p = doit ();
 885   return p;
 886 }