lib/Object/COFFObjectFile.cpp

   1 //===- COFFObjectFile.cpp - COFF object file implementation -----*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file declares the COFFObjectFile class.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/Object/COFF.h"
  15 #include "llvm/ADT/SmallString.h"
  16 #include "llvm/ADT/StringSwitch.h"
  17 #include "llvm/ADT/Triple.h"
  18
  19 using namespace llvm;
  20 using namespace object;
  21
  22 namespace {
  23 using support::ulittle8_t;
  24 using support::ulittle16_t;
  25 using support::ulittle32_t;
  26 using support::little16_t;
  27 }
  28
  29 namespace {
  30 // Returns false if size is greater than the buffer size. And sets ec.
  31 bool checkSize(const MemoryBuffer *m, error_code &ec, uint64_t size) {
  32   if (m->getBufferSize() < size) {
  33     ec = object_error::unexpected_eof;
  34     return false;
  35   }
  36   return true;
  37 }
  38
  39 // Returns false if any bytes in [addr, addr + size) fall outsize of m.
  40 bool checkAddr(const MemoryBuffer *m,
  41                error_code &ec,
  42                uintptr_t addr,
  43                uint64_t size) {
  44   if (addr + size < addr ||
  45       addr + size < size ||
  46       addr + size > uintptr_t(m->getBufferEnd())) {
  47     ec = object_error::unexpected_eof;
  48     return false;
  49   }
  50   return true;
  51 }
  52 }
  53
  54 const coff_symbol *COFFObjectFile::toSymb(DataRefImpl Symb) const {
  55   const coff_symbol *addr = reinterpret_cast<const coff_symbol*>(Symb.p);
  56
  57 # ifndef NDEBUG
  58   // Verify that the symbol points to a valid entry in the symbol table.
  59   uintptr_t offset = uintptr_t(addr) - uintptr_t(base());
  60   if (offset < Header->PointerToSymbolTable
  61       || offset >= Header->PointerToSymbolTable
  62          + (Header->NumberOfSymbols * sizeof(coff_symbol)))
  63     report_fatal_error("Symbol was outside of symbol table.");
  64
  65   assert((offset - Header->PointerToSymbolTable) % sizeof(coff_symbol)
  66          == 0 && "Symbol did not point to the beginning of a symbol");
  67 # endif
  68
  69   return addr;
  70 }
  71
  72 const coff_section *COFFObjectFile::toSec(DataRefImpl Sec) const {
  73   const coff_section *addr = reinterpret_cast<const coff_section*>(Sec.p);
  74
  75 # ifndef NDEBUG
  76   // Verify that the section points to a valid entry in the section table.
  77   if (addr < SectionTable
  78       || addr >= (SectionTable + Header->NumberOfSections))
  79     report_fatal_error("Section was outside of section table.");
  80
  81   uintptr_t offset = uintptr_t(addr) - uintptr_t(SectionTable);
  82   assert(offset % sizeof(coff_section) == 0 &&
  83          "Section did not point to the beginning of a section");
  84 # endif
  85
  86   return addr;
  87 }
  88
  89 error_code COFFObjectFile::getSymbolNext(DataRefImpl Symb,
  90                                          SymbolRef &Result) const {
  91   const coff_symbol *symb = toSymb(Symb);
  92   symb += 1 + symb->NumberOfAuxSymbols;
  93   Symb.p = reinterpret_cast<uintptr_t>(symb);
  94   Result = SymbolRef(Symb, this);
  95   return object_error::success;
  96 }
  97
  98  error_code COFFObjectFile::getSymbolName(DataRefImpl Symb,
  99                                           StringRef &Result) const {
 100   const coff_symbol *symb = toSymb(Symb);
 101   return getSymbolName(symb, Result);
 102 }
 103
 104 error_code COFFObjectFile::getSymbolFileOffset(DataRefImpl Symb,
 105                                             uint64_t &Result) const {
 106   const coff_symbol *symb = toSymb(Symb);
 107   const coff_section *Section = NULL;
 108   if (error_code ec = getSection(symb->SectionNumber, Section))
 109     return ec;
 110   char Type;
 111   if (error_code ec = getSymbolNMTypeChar(Symb, Type))
 112     return ec;
 113   if (Type == 'U' || Type == 'w')
 114     Result = UnknownAddressOrSize;
 115   else if (Section)
 116     Result = Section->PointerToRawData + symb->Value;
 117   else
 118     Result = symb->Value;
 119   return object_error::success;
 120 }
 121
 122 error_code COFFObjectFile::getSymbolAddress(DataRefImpl Symb,
 123                                             uint64_t &Result) const {
 124   const coff_symbol *symb = toSymb(Symb);
 125   const coff_section *Section = NULL;
 126   if (error_code ec = getSection(symb->SectionNumber, Section))
 127     return ec;
 128   char Type;
 129   if (error_code ec = getSymbolNMTypeChar(Symb, Type))
 130     return ec;
 131   if (Type == 'U' || Type == 'w')
 132     Result = UnknownAddressOrSize;
 133   else if (Section)
 134     Result = Section->VirtualAddress + symb->Value;
 135   else
 136     Result = symb->Value;
 137   return object_error::success;
 138 }
 139
 140 error_code COFFObjectFile::getSymbolType(DataRefImpl Symb,
 141                                          SymbolRef::Type &Result) const {
 142   const coff_symbol *symb = toSymb(Symb);
 143   Result = SymbolRef::ST_Other;
 144   if (symb->StorageClass == COFF::IMAGE_SYM_CLASS_EXTERNAL &&
 145       symb->SectionNumber == COFF::IMAGE_SYM_UNDEFINED) {
 146     Result = SymbolRef::ST_Unknown;
 147   } else {
 148     if (symb->getComplexType() == COFF::IMAGE_SYM_DTYPE_FUNCTION) {
 149       Result = SymbolRef::ST_Function;
 150     } else {
 151       char Type;
 152       if (error_code ec = getSymbolNMTypeChar(Symb, Type))
 153         return ec;
 154       if (Type == 'r' || Type == 'R') {
 155         Result = SymbolRef::ST_Data;
 156       }
 157     }
 158   }
 159   return object_error::success;
 160 }
 161
 162 error_code COFFObjectFile::getSymbolFlags(DataRefImpl Symb,
 163                                           uint32_t &Result) const {
 164   const coff_symbol *symb = toSymb(Symb);
 165   Result = SymbolRef::SF_None;
 166
 167   // TODO: Correctly set SF_FormatSpecific, SF_ThreadLocal, SF_Common
 168
 169   if (symb->StorageClass == COFF::IMAGE_SYM_CLASS_EXTERNAL &&
 170       symb->SectionNumber == COFF::IMAGE_SYM_UNDEFINED)
 171     Result |= SymbolRef::SF_Undefined;
 172
 173   // TODO: This are certainly too restrictive.
 174   if (symb->StorageClass == COFF::IMAGE_SYM_CLASS_EXTERNAL)
 175     Result |= SymbolRef::SF_Global;
 176
 177   if (symb->StorageClass == COFF::IMAGE_SYM_CLASS_WEAK_EXTERNAL)
 178     Result |= SymbolRef::SF_Weak;
 179
 180   if (symb->SectionNumber == COFF::IMAGE_SYM_ABSOLUTE)
 181     Result |= SymbolRef::SF_Absolute;
 182
 183   return object_error::success;
 184 }
 185
 186 error_code COFFObjectFile::getSymbolSize(DataRefImpl Symb,
 187                                          uint64_t &Result) const {
 188   // FIXME: Return the correct size. This requires looking at all the symbols
 189   //        in the same section as this symbol, and looking for either the next
 190   //        symbol, or the end of the section.
 191   const coff_symbol *symb = toSymb(Symb);
 192   const coff_section *Section = NULL;
 193   if (error_code ec = getSection(symb->SectionNumber, Section))
 194     return ec;
 195   char Type;
 196   if (error_code ec = getSymbolNMTypeChar(Symb, Type))
 197     return ec;
 198   if (Type == 'U' || Type == 'w')
 199     Result = UnknownAddressOrSize;
 200   else if (Section)
 201     Result = Section->SizeOfRawData - symb->Value;
 202   else
 203     Result = 0;
 204   return object_error::success;
 205 }
 206
 207 error_code COFFObjectFile::getSymbolNMTypeChar(DataRefImpl Symb,
 208                                                char &Result) const {
 209   const coff_symbol *symb = toSymb(Symb);
 210   StringRef name;
 211   if (error_code ec = getSymbolName(Symb, name))
 212     return ec;
 213   char ret = StringSwitch<char>(name)
 214     .StartsWith(".debug", 'N')
 215     .StartsWith(".sxdata", 'N')
 216     .Default('?');
 217
 218   if (ret != '?') {
 219     Result = ret;
 220     return object_error::success;
 221   }
 222
 223   uint32_t Characteristics = 0;
 224   if (symb->SectionNumber > 0) {
 225     const coff_section *Section = NULL;
 226     if (error_code ec = getSection(symb->SectionNumber, Section))
 227       return ec;
 228     Characteristics = Section->Characteristics;
 229   }
 230
 231   switch (symb->SectionNumber) {
 232   case COFF::IMAGE_SYM_UNDEFINED:
 233     // Check storage classes.
 234     if (symb->StorageClass == COFF::IMAGE_SYM_CLASS_WEAK_EXTERNAL) {
 235       Result = 'w';
 236       return object_error::success; // Don't do ::toupper.
 237     } else if (symb->Value != 0) // Check for common symbols.
 238       ret = 'c';
 239     else
 240       ret = 'u';
 241     break;
 242   case COFF::IMAGE_SYM_ABSOLUTE:
 243     ret = 'a';
 244     break;
 245   case COFF::IMAGE_SYM_DEBUG:
 246     ret = 'n';
 247     break;
 248   default:
 249     // Check section type.
 250     if (Characteristics & COFF::IMAGE_SCN_CNT_CODE)
 251       ret = 't';
 252     else if (  Characteristics & COFF::IMAGE_SCN_MEM_READ
 253             && ~Characteristics & COFF::IMAGE_SCN_MEM_WRITE) // Read only.
 254       ret = 'r';
 255     else if (Characteristics & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA)
 256       ret = 'd';
 257     else if (Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA)
 258       ret = 'b';
 259     else if (Characteristics & COFF::IMAGE_SCN_LNK_INFO)
 260       ret = 'i';
 261
 262     // Check for section symbol.
 263     else if (  symb->StorageClass == COFF::IMAGE_SYM_CLASS_STATIC
 264             && symb->Value == 0)
 265        ret = 's';
 266   }
 267
 268   if (symb->StorageClass == COFF::IMAGE_SYM_CLASS_EXTERNAL)
 269     ret = ::toupper(ret);
 270
 271   Result = ret;
 272   return object_error::success;
 273 }
 274
 275 error_code COFFObjectFile::getSymbolSection(DataRefImpl Symb,
 276                                             section_iterator &Result) const {
 277   const coff_symbol *symb = toSymb(Symb);
 278   if (symb->SectionNumber <= COFF::IMAGE_SYM_UNDEFINED)
 279     Result = end_sections();
 280   else {
 281     const coff_section *sec = 0;
 282     if (error_code ec = getSection(symb->SectionNumber, sec)) return ec;
 283     DataRefImpl Sec;
 284     std::memset(&Sec, 0, sizeof(Sec));
 285     Sec.p = reinterpret_cast<uintptr_t>(sec);
 286     Result = section_iterator(SectionRef(Sec, this));
 287   }
 288   return object_error::success;
 289 }
 290
 291 error_code COFFObjectFile::getSectionNext(DataRefImpl Sec,
 292                                           SectionRef &Result) const {
 293   const coff_section *sec = toSec(Sec);
 294   sec += 1;
 295   Sec.p = reinterpret_cast<uintptr_t>(sec);
 296   Result = SectionRef(Sec, this);
 297   return object_error::success;
 298 }
 299
 300 error_code COFFObjectFile::getSectionName(DataRefImpl Sec,
 301                                           StringRef &Result) const {
 302   const coff_section *sec = toSec(Sec);
 303   return getSectionName(sec, Result);
 304 }
 305
 306 error_code COFFObjectFile::getSectionAddress(DataRefImpl Sec,
 307                                              uint64_t &Result) const {
 308   const coff_section *sec = toSec(Sec);
 309   Result = sec->VirtualAddress;
 310   return object_error::success;
 311 }
 312
 313 error_code COFFObjectFile::getSectionSize(DataRefImpl Sec,
 314                                           uint64_t &Result) const {
 315   const coff_section *sec = toSec(Sec);
 316   Result = sec->SizeOfRawData;
 317   return object_error::success;
 318 }
 319
 320 error_code COFFObjectFile::getSectionContents(DataRefImpl Sec,
 321                                               StringRef &Result) const {
 322   const coff_section *sec = toSec(Sec);
 323   // The only thing that we need to verify is that the contents is contained
 324   // within the file bounds. We don't need to make sure it doesn't cover other
 325   // data, as there's nothing that says that is not allowed.
 326   uintptr_t con_start = uintptr_t(base()) + sec->PointerToRawData;
 327   uintptr_t con_end = con_start + sec->SizeOfRawData;
 328   if (con_end > uintptr_t(Data->getBufferEnd()))
 329     return object_error::parse_failed;
 330   Result = StringRef(reinterpret_cast<const char*>(con_start),
 331                      sec->SizeOfRawData);
 332   return object_error::success;
 333 }
 334
 335 error_code COFFObjectFile::getSectionAlignment(DataRefImpl Sec,
 336                                                uint64_t &Res) const {
 337   const coff_section *sec = toSec(Sec);
 338   if (!sec)
 339     return object_error::parse_failed;
 340   Res = uint64_t(1) << (((sec->Characteristics & 0x00F00000) >> 20) - 1);
 341   return object_error::success;
 342 }
 343
 344 error_code COFFObjectFile::isSectionText(DataRefImpl Sec,
 345                                          bool &Result) const {
 346   const coff_section *sec = toSec(Sec);
 347   Result = sec->Characteristics & COFF::IMAGE_SCN_CNT_CODE;
 348   return object_error::success;
 349 }
 350
 351 error_code COFFObjectFile::isSectionData(DataRefImpl Sec,
 352                                          bool &Result) const {
 353   const coff_section *sec = toSec(Sec);
 354   Result = sec->Characteristics & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA;
 355   return object_error::success;
 356 }
 357
 358 error_code COFFObjectFile::isSectionBSS(DataRefImpl Sec,
 359                                         bool &Result) const {
 360   const coff_section *sec = toSec(Sec);
 361   Result = sec->Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA;
 362   return object_error::success;
 363 }
 364
 365 error_code COFFObjectFile::sectionContainsSymbol(DataRefImpl Sec,
 366                                                  DataRefImpl Symb,
 367                                                  bool &Result) const {
 368   const coff_section *sec = toSec(Sec);
 369   const coff_symbol *symb = toSymb(Symb);
 370   const coff_section *symb_sec = 0;
 371   if (error_code ec = getSection(symb->SectionNumber, symb_sec)) return ec;
 372   if (symb_sec == sec)
 373     Result = true;
 374   else
 375     Result = false;
 376   return object_error::success;
 377 }
 378
 379 relocation_iterator COFFObjectFile::getSectionRelBegin(DataRefImpl Sec) const {
 380   const coff_section *sec = toSec(Sec);
 381   DataRefImpl ret;
 382   std::memset(&ret, 0, sizeof(ret));
 383   if (sec->NumberOfRelocations == 0)
 384     ret.p = 0;
 385   else
 386     ret.p = reinterpret_cast<uintptr_t>(base() + sec->PointerToRelocations);
 387
 388   return relocation_iterator(RelocationRef(ret, this));
 389 }
 390
 391 relocation_iterator COFFObjectFile::getSectionRelEnd(DataRefImpl Sec) const {
 392   const coff_section *sec = toSec(Sec);
 393   DataRefImpl ret;
 394   std::memset(&ret, 0, sizeof(ret));
 395   if (sec->NumberOfRelocations == 0)
 396     ret.p = 0;
 397   else
 398     ret.p = reinterpret_cast<uintptr_t>(
 399               reinterpret_cast<const coff_relocation*>(
 400                 base() + sec->PointerToRelocations)
 401               + sec->NumberOfRelocations);
 402
 403   return relocation_iterator(RelocationRef(ret, this));
 404 }
 405
 406 COFFObjectFile::COFFObjectFile(MemoryBuffer *Object, error_code &ec)
 407   : ObjectFile(Binary::ID_COFF, Object, ec)
 408   , Header(0)
 409   , SectionTable(0)
 410   , SymbolTable(0)
 411   , StringTable(0)
 412   , StringTableSize(0) {
 413   // Check that we at least have enough room for a header.
 414   if (!checkSize(Data, ec, sizeof(coff_file_header))) return;
 415
 416   // The actual starting location of the COFF header in the file. This can be
 417   // non-zero in PE/COFF files.
 418   uint64_t HeaderStart = 0;
 419
 420   // Check if this is a PE/COFF file.
 421   if (base()[0] == 0x4d && base()[1] == 0x5a) {
 422     // PE/COFF, seek through MS-DOS compatibility stub and 4-byte
 423     // PE signature to find 'normal' COFF header.
 424     if (!checkSize(Data, ec, 0x3c + 8)) return;
 425     HeaderStart = *reinterpret_cast<const ulittle16_t *>(base() + 0x3c);
 426     // Check the PE header. ("PE\0\0")
 427     if (std::memcmp(base() + HeaderStart, "PE\0\0", 4) != 0) {
 428       ec = object_error::parse_failed;
 429       return;
 430     }
 431     HeaderStart += 4; // Skip the PE Header.
 432   }
 433
 434   Header = reinterpret_cast<const coff_file_header *>(base() + HeaderStart);
 435   if (!checkAddr(Data, ec, uintptr_t(Header), sizeof(coff_file_header)))
 436     return;
 437
 438   SectionTable =
 439     reinterpret_cast<const coff_section *>( base()
 440                                           + HeaderStart
 441                                           + sizeof(coff_file_header)
 442                                           + Header->SizeOfOptionalHeader);
 443   if (!checkAddr(Data, ec, uintptr_t(SectionTable),
 444                  Header->NumberOfSections * sizeof(coff_section)))
 445     return;
 446
 447   if (Header->PointerToSymbolTable != 0) {
 448     SymbolTable =
 449       reinterpret_cast<const coff_symbol *>(base()
 450                                             + Header->PointerToSymbolTable);
 451     if (!checkAddr(Data, ec, uintptr_t(SymbolTable),
 452                    Header->NumberOfSymbols * sizeof(coff_symbol)))
 453       return;
 454
 455     // Find string table.
 456     StringTable = reinterpret_cast<const char *>(base())
 457                   + Header->PointerToSymbolTable
 458                   + Header->NumberOfSymbols * sizeof(coff_symbol);
 459     if (!checkAddr(Data, ec, uintptr_t(StringTable), sizeof(ulittle32_t)))
 460       return;
 461
 462     StringTableSize = *reinterpret_cast<const ulittle32_t *>(StringTable);
 463     if (!checkAddr(Data, ec, uintptr_t(StringTable), StringTableSize))
 464       return;
 465     // Check that the string table is null terminated if has any in it.
 466     if (StringTableSize < 4
 467         || (StringTableSize > 4 && StringTable[StringTableSize - 1] != 0)) {
 468       ec = object_error::parse_failed;
 469       return;
 470     }
 471   }
 472
 473   ec = object_error::success;
 474 }
 475
 476 symbol_iterator COFFObjectFile::begin_symbols() const {
 477   DataRefImpl ret;
 478   std::memset(&ret, 0, sizeof(DataRefImpl));
 479   ret.p = reinterpret_cast<intptr_t>(SymbolTable);
 480   return symbol_iterator(SymbolRef(ret, this));
 481 }
 482
 483 symbol_iterator COFFObjectFile::end_symbols() const {
 484   // The symbol table ends where the string table begins.
 485   DataRefImpl ret;
 486   std::memset(&ret, 0, sizeof(DataRefImpl));
 487   ret.p = reinterpret_cast<intptr_t>(StringTable);
 488   return symbol_iterator(SymbolRef(ret, this));
 489 }
 490
 491 symbol_iterator COFFObjectFile::begin_dynamic_symbols() const {
 492   // TODO: implement
 493   report_fatal_error("Dynamic symbols unimplemented in COFFObjectFile");
 494 }
 495
 496 symbol_iterator COFFObjectFile::end_dynamic_symbols() const {
 497   // TODO: implement
 498   report_fatal_error("Dynamic symbols unimplemented in COFFObjectFile");
 499 }
 500
 501 library_iterator COFFObjectFile::begin_libraries_needed() const {
 502   // TODO: implement
 503   report_fatal_error("Libraries needed unimplemented in COFFObjectFile");
 504 }
 505
 506 library_iterator COFFObjectFile::end_libraries_needed() const {
 507   // TODO: implement
 508   report_fatal_error("Libraries needed unimplemented in COFFObjectFile");
 509 }
 510
 511 StringRef COFFObjectFile::getLoadName() const {
 512   // COFF does not have this field.
 513   return "";
 514 }
 515
 516
 517 section_iterator COFFObjectFile::begin_sections() const {
 518   DataRefImpl ret;
 519   std::memset(&ret, 0, sizeof(DataRefImpl));
 520   ret.p = reinterpret_cast<intptr_t>(SectionTable);
 521   return section_iterator(SectionRef(ret, this));
 522 }
 523
 524 section_iterator COFFObjectFile::end_sections() const {
 525   DataRefImpl ret;
 526   std::memset(&ret, 0, sizeof(DataRefImpl));
 527   ret.p = reinterpret_cast<intptr_t>(SectionTable + Header->NumberOfSections);
 528   return section_iterator(SectionRef(ret, this));
 529 }
 530
 531 uint8_t COFFObjectFile::getBytesInAddress() const {
 532   return getArch() == Triple::x86_64 ? 8 : 4;
 533 }
 534
 535 StringRef COFFObjectFile::getFileFormatName() const {
 536   switch(Header->Machine) {
 537   case COFF::IMAGE_FILE_MACHINE_I386:
 538     return "COFF-i386";
 539   case COFF::IMAGE_FILE_MACHINE_AMD64:
 540     return "COFF-x86-64";
 541   default:
 542     return "COFF-<unknown arch>";
 543   }
 544 }
 545
 546 unsigned COFFObjectFile::getArch() const {
 547   switch(Header->Machine) {
 548   case COFF::IMAGE_FILE_MACHINE_I386:
 549     return Triple::x86;
 550   case COFF::IMAGE_FILE_MACHINE_AMD64:
 551     return Triple::x86_64;
 552   default:
 553     return Triple::UnknownArch;
 554   }
 555 }
 556
 557 error_code COFFObjectFile::getHeader(const coff_file_header *&Res) const {
 558   Res = Header;
 559   return object_error::success;
 560 }
 561
 562 error_code COFFObjectFile::getSection(int32_t index,
 563                                       const coff_section *&Result) const {
 564   // Check for special index values.
 565   if (index == COFF::IMAGE_SYM_UNDEFINED ||
 566       index == COFF::IMAGE_SYM_ABSOLUTE ||
 567       index == COFF::IMAGE_SYM_DEBUG)
 568     Result = NULL;
 569   else if (index > 0 && index <= Header->NumberOfSections)
 570     // We already verified the section table data, so no need to check again.
 571     Result = SectionTable + (index - 1);
 572   else
 573     return object_error::parse_failed;
 574   return object_error::success;
 575 }
 576
 577 error_code COFFObjectFile::getString(uint32_t offset,
 578                                      StringRef &Result) const {
 579   if (StringTableSize <= 4)
 580     // Tried to get a string from an empty string table.
 581     return object_error::parse_failed;
 582   if (offset >= StringTableSize)
 583     return object_error::unexpected_eof;
 584   Result = StringRef(StringTable + offset);
 585   return object_error::success;
 586 }
 587
 588 error_code COFFObjectFile::getSymbol(uint32_t index,
 589                                      const coff_symbol *&Result) const {
 590   if (index < Header->NumberOfSymbols)
 591     Result = SymbolTable + index;
 592   else
 593     return object_error::parse_failed;
 594   return object_error::success;
 595 }
 596
 597 error_code COFFObjectFile::getSymbolName(const coff_symbol *symbol,
 598                                          StringRef &Res) const {
 599   // Check for string table entry. First 4 bytes are 0.
 600   if (symbol->Name.Offset.Zeroes == 0) {
 601     uint32_t Offset = symbol->Name.Offset.Offset;
 602     if (error_code ec = getString(Offset, Res))
 603       return ec;
 604     return object_error::success;
 605   }
 606
 607   if (symbol->Name.ShortName[7] == 0)
 608     // Null terminated, let ::strlen figure out the length.
 609     Res = StringRef(symbol->Name.ShortName);
 610   else
 611     // Not null terminated, use all 8 bytes.
 612     Res = StringRef(symbol->Name.ShortName, 8);
 613   return object_error::success;
 614 }
 615
 616 error_code COFFObjectFile::getSectionName(const coff_section *Sec,
 617                                           StringRef &Res) const {
 618   StringRef Name;
 619   if (Sec->Name[7] == 0)
 620     // Null terminated, let ::strlen figure out the length.
 621     Name = Sec->Name;
 622   else
 623     // Not null terminated, use all 8 bytes.
 624     Name = StringRef(Sec->Name, 8);
 625
 626   // Check for string table entry. First byte is '/'.
 627   if (Name[0] == '/') {
 628     uint32_t Offset;
 629     if (Name.substr(1).getAsInteger(10, Offset))
 630       return object_error::parse_failed;
 631     if (error_code ec = getString(Offset, Name))
 632       return ec;
 633   }
 634
 635   Res = Name;
 636   return object_error::success;
 637 }
 638
 639 const coff_relocation *COFFObjectFile::toRel(DataRefImpl Rel) const {
 640   return reinterpret_cast<const coff_relocation*>(Rel.p);
 641 }
 642 error_code COFFObjectFile::getRelocationNext(DataRefImpl Rel,
 643                                              RelocationRef &Res) const {
 644   Rel.p = reinterpret_cast<uintptr_t>(
 645             reinterpret_cast<const coff_relocation*>(Rel.p) + 1);
 646   Res = RelocationRef(Rel, this);
 647   return object_error::success;
 648 }
 649 error_code COFFObjectFile::getRelocationAddress(DataRefImpl Rel,
 650                                                 uint64_t &Res) const {
 651   Res = toRel(Rel)->VirtualAddress;
 652   return object_error::success;
 653 }
 654 error_code COFFObjectFile::getRelocationOffset(DataRefImpl Rel,
 655                                                uint64_t &Res) const {
 656   Res = toRel(Rel)->VirtualAddress;
 657   return object_error::success;
 658 }
 659 error_code COFFObjectFile::getRelocationSymbol(DataRefImpl Rel,
 660                                                SymbolRef &Res) const {
 661   const coff_relocation* R = toRel(Rel);
 662   DataRefImpl Symb;
 663   std::memset(&Symb, 0, sizeof(Symb));
 664   Symb.p = reinterpret_cast<uintptr_t>(SymbolTable + R->SymbolTableIndex);
 665   Res = SymbolRef(Symb, this);
 666   return object_error::success;
 667 }
 668 error_code COFFObjectFile::getRelocationType(DataRefImpl Rel,
 669                                              uint64_t &Res) const {
 670   const coff_relocation* R = toRel(Rel);
 671   Res = R->Type;
 672   return object_error::success;
 673 }
 674
 675 #define LLVM_COFF_SWITCH_RELOC_TYPE_NAME(enum) \
 676   case COFF::enum: res = #enum; break;
 677
 678 error_code COFFObjectFile::getRelocationTypeName(DataRefImpl Rel,
 679                                           SmallVectorImpl<char> &Result) const {
 680   const coff_relocation *reloc = toRel(Rel);
 681   StringRef res;
 682   switch (Header->Machine) {
 683   case COFF::IMAGE_FILE_MACHINE_AMD64:
 684     switch (reloc->Type) {
 685     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ABSOLUTE);
 686     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ADDR64);
 687     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ADDR32);
 688     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ADDR32NB);
 689     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32);
 690     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_1);
 691     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_2);
 692     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_3);
 693     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_4);
 694     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_5);
 695     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SECTION);
 696     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SECREL);
 697     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SECREL7);
 698     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_TOKEN);
 699     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SREL32);
 700     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_PAIR);
 701     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SSPAN32);
 702     default:
 703       res = "Unknown";
 704     }
 705     break;
 706   case COFF::IMAGE_FILE_MACHINE_I386:
 707     switch (reloc->Type) {
 708     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_ABSOLUTE);
 709     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_DIR16);
 710     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_REL16);
 711     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_DIR32);
 712     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_DIR32NB);
 713     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SEG12);
 714     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SECTION);
 715     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SECREL);
 716     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_TOKEN);
 717     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SECREL7);
 718     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_REL32);
 719     default:
 720       res = "Unknown";
 721     }
 722     break;
 723   default:
 724     res = "Unknown";
 725   }
 726   Result.append(res.begin(), res.end());
 727   return object_error::success;
 728 }
 729
 730 #undef LLVM_COFF_SWITCH_RELOC_TYPE_NAME
 731
 732 error_code COFFObjectFile::getRelocationAdditionalInfo(DataRefImpl Rel,
 733                                                        int64_t &Res) const {
 734   Res = 0;
 735   return object_error::success;
 736 }
 737 error_code COFFObjectFile::getRelocationValueString(DataRefImpl Rel,
 738                                           SmallVectorImpl<char> &Result) const {
 739   const coff_relocation *reloc = toRel(Rel);
 740   const coff_symbol *symb = 0;
 741   if (error_code ec = getSymbol(reloc->SymbolTableIndex, symb)) return ec;
 742   DataRefImpl sym;
 743   ::memset(&sym, 0, sizeof(sym));
 744   sym.p = reinterpret_cast<uintptr_t>(symb);
 745   StringRef symname;
 746   if (error_code ec = getSymbolName(sym, symname)) return ec;
 747   Result.append(symname.begin(), symname.end());
 748   return object_error::success;
 749 }
 750
 751 error_code COFFObjectFile::getLibraryNext(DataRefImpl LibData,
 752                                           LibraryRef &Result) const {
 753   report_fatal_error("getLibraryNext not implemented in COFFObjectFile");
 754 }
 755
 756 error_code COFFObjectFile::getLibraryPath(DataRefImpl LibData,
 757                                           StringRef &Result) const {
 758   report_fatal_error("getLibraryPath not implemented in COFFObjectFile");
 759 }
 760
 761 namespace llvm {
 762
 763   ObjectFile *ObjectFile::createCOFFObjectFile(MemoryBuffer *Object) {
 764     error_code ec;
 765     return new COFFObjectFile(Object, ec);
 766   }
 767
 768 } // end namespace llvm