llvm/lib/ToolDrivers/llvm-lib/LibDriver.cpp

   1 //===- LibDriver.cpp - lib.exe-compatible driver --------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // Defines an interface to a lib.exe-compatible driver that also understands
  10 // bitcode files. Used by llvm-lib and lld-link /lib.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/ToolDrivers/llvm-lib/LibDriver.h"
  15 #include "llvm/ADT/STLExtras.h"
  16 #include "llvm/ADT/StringSet.h"
  17 #include "llvm/BinaryFormat/COFF.h"
  18 #include "llvm/BinaryFormat/Magic.h"
  19 #include "llvm/Bitcode/BitcodeReader.h"
  20 #include "llvm/Object/ArchiveWriter.h"
  21 #include "llvm/Object/COFF.h"
  22 #include "llvm/Object/COFFModuleDefinition.h"
  23 #include "llvm/Object/WindowsMachineFlag.h"
  24 #include "llvm/Option/Arg.h"
  25 #include "llvm/Option/ArgList.h"
  26 #include "llvm/Option/OptTable.h"
  27 #include "llvm/Option/Option.h"
  28 #include "llvm/Support/CommandLine.h"
  29 #include "llvm/Support/Path.h"
  30 #include "llvm/Support/Process.h"
  31 #include "llvm/Support/StringSaver.h"
  32 #include "llvm/Support/raw_ostream.h"
  33 #include <optional>
  34
  35 using namespace llvm;
  36 using namespace llvm::object;
  37
  38 namespace {
  39
  40 enum {
  41   OPT_INVALID = 0,
  42 #define OPTION(...) LLVM_MAKE_OPT_ID(__VA_ARGS__),
  43 #include "Options.inc"
  44 #undef OPTION
  45 };
  46
  47 #define PREFIX(NAME, VALUE)                                                    \
  48   static constexpr StringLiteral NAME##_init[] = VALUE;                        \
  49   static constexpr ArrayRef<StringLiteral> NAME(NAME##_init,                   \
  50                                                 std::size(NAME##_init) - 1);
  51 #include "Options.inc"
  52 #undef PREFIX
  53
  54 using namespace llvm::opt;
  55 static constexpr opt::OptTable::Info InfoTable[] = {
  56 #define OPTION(...) LLVM_CONSTRUCT_OPT_INFO(__VA_ARGS__),
  57 #include "Options.inc"
  58 #undef OPTION
  59 };
  60
  61 class LibOptTable : public opt::GenericOptTable {
  62 public:
  63   LibOptTable() : opt::GenericOptTable(InfoTable, true) {}
  64 };
  65 } // namespace
  66
  67 static std::string getDefaultOutputPath(const NewArchiveMember &FirstMember) {
  68   SmallString<128> Val = StringRef(FirstMember.Buf->getBufferIdentifier());
  69   sys::path::replace_extension(Val, ".lib");
  70   return std::string(Val);
  71 }
  72
  73 static std::vector<StringRef> getSearchPaths(opt::InputArgList *Args,
  74                                              StringSaver &Saver) {
  75   std::vector<StringRef> Ret;
  76   // Add current directory as first item of the search path.
  77   Ret.push_back("");
  78
  79   // Add /libpath flags.
  80   for (auto *Arg : Args->filtered(OPT_libpath))
  81     Ret.push_back(Arg->getValue());
  82
  83   // Add $LIB.
  84   std::optional<std::string> EnvOpt = sys::Process::GetEnv("LIB");
  85   if (!EnvOpt)
  86     return Ret;
  87   StringRef Env = Saver.save(*EnvOpt);
  88   while (!Env.empty()) {
  89     StringRef Path;
  90     std::tie(Path, Env) = Env.split(';');
  91     Ret.push_back(Path);
  92   }
  93   return Ret;
  94 }
  95
  96 // Opens a file. Path has to be resolved already. (used for def file)
  97 std::unique_ptr<MemoryBuffer> openFile(const Twine &Path) {
  98   ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> MB =
  99       MemoryBuffer::getFile(Path, /*IsText=*/true);
 100
 101   if (std::error_code EC = MB.getError()) {
 102     llvm::errs() << "cannot open file " << Path << ": " << EC.message() << "\n";
 103     return nullptr;
 104   }
 105
 106   return std::move(*MB);
 107 }
 108
 109 static std::string findInputFile(StringRef File, ArrayRef<StringRef> Paths) {
 110   for (StringRef Dir : Paths) {
 111     SmallString<128> Path = Dir;
 112     sys::path::append(Path, File);
 113     if (sys::fs::exists(Path))
 114       return std::string(Path);
 115   }
 116   return "";
 117 }
 118
 119 static void fatalOpenError(llvm::Error E, Twine File) {
 120   if (!E)
 121     return;
 122   handleAllErrors(std::move(E), [&](const llvm::ErrorInfoBase &EIB) {
 123     llvm::errs() << "error opening '" << File << "': " << EIB.message() << '\n';
 124     exit(1);
 125   });
 126 }
 127
 128 static void doList(opt::InputArgList &Args) {
 129   // lib.exe prints the contents of the first archive file.
 130   std::unique_ptr<MemoryBuffer> B;
 131   for (auto *Arg : Args.filtered(OPT_INPUT)) {
 132     // Create or open the archive object.
 133     ErrorOr<std::unique_ptr<MemoryBuffer>> MaybeBuf = MemoryBuffer::getFile(
 134         Arg->getValue(), /*IsText=*/false, /*RequiresNullTerminator=*/false);
 135     fatalOpenError(errorCodeToError(MaybeBuf.getError()), Arg->getValue());
 136
 137     if (identify_magic(MaybeBuf.get()->getBuffer()) == file_magic::archive) {
 138       B = std::move(MaybeBuf.get());
 139       break;
 140     }
 141   }
 142
 143   // lib.exe doesn't print an error if no .lib files are passed.
 144   if (!B)
 145     return;
 146
 147   Error Err = Error::success();
 148   object::Archive Archive(B->getMemBufferRef(), Err);
 149   fatalOpenError(std::move(Err), B->getBufferIdentifier());
 150
 151   std::vector<StringRef> Names;
 152   for (auto &C : Archive.children(Err)) {
 153     Expected<StringRef> NameOrErr = C.getName();
 154     fatalOpenError(NameOrErr.takeError(), B->getBufferIdentifier());
 155     Names.push_back(NameOrErr.get());
 156   }
 157   for (auto Name : reverse(Names))
 158     llvm::outs() << Name << '\n';
 159   fatalOpenError(std::move(Err), B->getBufferIdentifier());
 160 }
 161
 162 static Expected<COFF::MachineTypes> getCOFFFileMachine(MemoryBufferRef MB) {
 163   std::error_code EC;
 164   auto Obj = object::COFFObjectFile::create(MB);
 165   if (!Obj)
 166     return Obj.takeError();
 167
 168   uint16_t Machine = (*Obj)->getMachine();
 169   if (Machine != COFF::IMAGE_FILE_MACHINE_I386 &&
 170       Machine != COFF::IMAGE_FILE_MACHINE_AMD64 &&
 171       Machine != COFF::IMAGE_FILE_MACHINE_ARMNT && !COFF::isAnyArm64(Machine)) {
 172     return createStringError(inconvertibleErrorCode(),
 173                              "unknown machine: " + std::to_string(Machine));
 174   }
 175
 176   return static_cast<COFF::MachineTypes>(Machine);
 177 }
 178
 179 static Expected<COFF::MachineTypes> getBitcodeFileMachine(MemoryBufferRef MB) {
 180   Expected<std::string> TripleStr = getBitcodeTargetTriple(MB);
 181   if (!TripleStr)
 182     return TripleStr.takeError();
 183
 184   Triple T(*TripleStr);
 185   switch (T.getArch()) {
 186   case Triple::x86:
 187     return COFF::IMAGE_FILE_MACHINE_I386;
 188   case Triple::x86_64:
 189     return COFF::IMAGE_FILE_MACHINE_AMD64;
 190   case Triple::arm:
 191     return COFF::IMAGE_FILE_MACHINE_ARMNT;
 192   case Triple::aarch64:
 193     return T.isWindowsArm64EC() ? COFF::IMAGE_FILE_MACHINE_ARM64EC
 194                                 : COFF::IMAGE_FILE_MACHINE_ARM64;
 195   default:
 196     return createStringError(inconvertibleErrorCode(),
 197                              "unknown arch in target triple: " + *TripleStr);
 198   }
 199 }
 200
 201 static bool machineMatches(COFF::MachineTypes LibMachine,
 202                            COFF::MachineTypes FileMachine) {
 203   if (LibMachine == FileMachine)
 204     return true;
 205   // ARM64EC mode allows both pure ARM64, ARM64EC and X64 objects to be mixed in
 206   // the archive.
 207   switch (LibMachine) {
 208   case COFF::IMAGE_FILE_MACHINE_ARM64:
 209     return FileMachine == COFF::IMAGE_FILE_MACHINE_ARM64X;
 210   case COFF::IMAGE_FILE_MACHINE_ARM64EC:
 211   case COFF::IMAGE_FILE_MACHINE_ARM64X:
 212     return COFF::isAnyArm64(FileMachine) ||
 213            FileMachine == COFF::IMAGE_FILE_MACHINE_AMD64;
 214   default:
 215     return false;
 216   }
 217 }
 218
 219 static void appendFile(std::vector<NewArchiveMember> &Members,
 220                        COFF::MachineTypes &LibMachine,
 221                        std::string &LibMachineSource, MemoryBufferRef MB) {
 222   file_magic Magic = identify_magic(MB.getBuffer());
 223
 224   if (Magic != file_magic::coff_object && Magic != file_magic::bitcode &&
 225       Magic != file_magic::archive && Magic != file_magic::windows_resource &&
 226       Magic != file_magic::coff_import_library) {
 227     llvm::errs() << MB.getBufferIdentifier()
 228                  << ": not a COFF object, bitcode, archive, import library or "
 229                     "resource file\n";
 230     exit(1);
 231   }
 232
 233   // If a user attempts to add an archive to another archive, llvm-lib doesn't
 234   // handle the first archive file as a single file. Instead, it extracts all
 235   // members from the archive and add them to the second archive. This behavior
 236   // is for compatibility with Microsoft's lib command.
 237   if (Magic == file_magic::archive) {
 238     Error Err = Error::success();
 239     object::Archive Archive(MB, Err);
 240     fatalOpenError(std::move(Err), MB.getBufferIdentifier());
 241
 242     for (auto &C : Archive.children(Err)) {
 243       Expected<MemoryBufferRef> ChildMB = C.getMemoryBufferRef();
 244       if (!ChildMB) {
 245         handleAllErrors(ChildMB.takeError(), [&](const ErrorInfoBase &EIB) {
 246           llvm::errs() << MB.getBufferIdentifier() << ": " << EIB.message()
 247                        << "\n";
 248         });
 249         exit(1);
 250       }
 251
 252       appendFile(Members, LibMachine, LibMachineSource, *ChildMB);
 253     }
 254
 255     fatalOpenError(std::move(Err), MB.getBufferIdentifier());
 256     return;
 257   }
 258
 259   // Check that all input files have the same machine type.
 260   // Mixing normal objects and LTO bitcode files is fine as long as they
 261   // have the same machine type.
 262   // Doing this here duplicates the header parsing work that writeArchive()
 263   // below does, but it's not a lot of work and it's a bit awkward to do
 264   // in writeArchive() which needs to support many tools, can't assume the
 265   // input is COFF, and doesn't have a good way to report errors.
 266   if (Magic == file_magic::coff_object || Magic == file_magic::bitcode) {
 267     Expected<COFF::MachineTypes> MaybeFileMachine =
 268         (Magic == file_magic::coff_object) ? getCOFFFileMachine(MB)
 269                                            : getBitcodeFileMachine(MB);
 270     if (!MaybeFileMachine) {
 271       handleAllErrors(MaybeFileMachine.takeError(),
 272                       [&](const ErrorInfoBase &EIB) {
 273                         llvm::errs() << MB.getBufferIdentifier() << ": "
 274                                      << EIB.message() << "\n";
 275                       });
 276       exit(1);
 277     }
 278     COFF::MachineTypes FileMachine = *MaybeFileMachine;
 279
 280     // FIXME: Once lld-link rejects multiple resource .obj files:
 281     // Call convertResToCOFF() on .res files and add the resulting
 282     // COFF file to the .lib output instead of adding the .res file, and remove
 283     // this check. See PR42180.
 284     if (FileMachine != COFF::IMAGE_FILE_MACHINE_UNKNOWN) {
 285       if (LibMachine == COFF::IMAGE_FILE_MACHINE_UNKNOWN) {
 286         if (FileMachine == COFF::IMAGE_FILE_MACHINE_ARM64EC) {
 287             llvm::errs() << MB.getBufferIdentifier() << ": file machine type "
 288                          << machineToStr(FileMachine)
 289                          << " conflicts with inferred library machine type,"
 290                          << " use /machine:arm64ec or /machine:arm64x\n";
 291             exit(1);
 292         }
 293         LibMachine = FileMachine;
 294         LibMachineSource =
 295             (" (inferred from earlier file '" + MB.getBufferIdentifier() + "')")
 296                 .str();
 297       } else if (!machineMatches(LibMachine, FileMachine)) {
 298         llvm::errs() << MB.getBufferIdentifier() << ": file machine type "
 299                      << machineToStr(FileMachine)
 300                      << " conflicts with library machine type "
 301                      << machineToStr(LibMachine) << LibMachineSource << '\n';
 302         exit(1);
 303       }
 304     }
 305   }
 306
 307   Members.emplace_back(MB);
 308 }
 309
 310 int llvm::libDriverMain(ArrayRef<const char *> ArgsArr) {
 311   BumpPtrAllocator Alloc;
 312   StringSaver Saver(Alloc);
 313
 314   // Parse command line arguments.
 315   SmallVector<const char *, 20> NewArgs(ArgsArr.begin(), ArgsArr.end());
 316   cl::ExpandResponseFiles(Saver, cl::TokenizeWindowsCommandLine, NewArgs);
 317   ArgsArr = NewArgs;
 318
 319   LibOptTable Table;
 320   unsigned MissingIndex;
 321   unsigned MissingCount;
 322   opt::InputArgList Args =
 323       Table.ParseArgs(ArgsArr.slice(1), MissingIndex, MissingCount);
 324   if (MissingCount) {
 325     llvm::errs() << "missing arg value for \""
 326                  << Args.getArgString(MissingIndex) << "\", expected "
 327                  << MissingCount
 328                  << (MissingCount == 1 ? " argument.\n" : " arguments.\n");
 329     return 1;
 330   }
 331   for (auto *Arg : Args.filtered(OPT_UNKNOWN))
 332     llvm::errs() << "ignoring unknown argument: " << Arg->getAsString(Args)
 333                  << "\n";
 334
 335   // Handle /help
 336   if (Args.hasArg(OPT_help)) {
 337     Table.printHelp(outs(), "llvm-lib [options] file...", "LLVM Lib");
 338     return 0;
 339   }
 340
 341   // Parse /ignore:
 342   llvm::StringSet<> IgnoredWarnings;
 343   for (auto *Arg : Args.filtered(OPT_ignore))
 344     IgnoredWarnings.insert(Arg->getValue());
 345
 346   // get output library path, if any
 347   std::string OutputPath;
 348   if (auto *Arg = Args.getLastArg(OPT_out)) {
 349     OutputPath = Arg->getValue();
 350   }
 351
 352   COFF::MachineTypes LibMachine = COFF::IMAGE_FILE_MACHINE_UNKNOWN;
 353   std::string LibMachineSource;
 354   if (auto *Arg = Args.getLastArg(OPT_machine)) {
 355     LibMachine = getMachineType(Arg->getValue());
 356     if (LibMachine == COFF::IMAGE_FILE_MACHINE_UNKNOWN) {
 357       llvm::errs() << "unknown /machine: arg " << Arg->getValue() << '\n';
 358       return 1;
 359     }
 360     LibMachineSource =
 361         std::string(" (from '/machine:") + Arg->getValue() + "' flag)";
 362   }
 363
 364   // create an import library
 365   if (Args.hasArg(OPT_deffile)) {
 366
 367     if (OutputPath.empty()) {
 368       llvm::errs() << "no output path given\n";
 369       return 1;
 370     }
 371
 372     if (LibMachine == COFF::IMAGE_FILE_MACHINE_UNKNOWN) {
 373       llvm::errs() << "/def option requires /machine to be specified" << '\n';
 374       return 1;
 375     }
 376
 377     std::unique_ptr<MemoryBuffer> MB =
 378         openFile(Args.getLastArg(OPT_deffile)->getValue());
 379     if (!MB)
 380       return 1;
 381
 382     if (!MB->getBufferSize()) {
 383       llvm::errs() << "definition file empty\n";
 384       return 1;
 385     }
 386
 387     Expected<COFFModuleDefinition> Def =
 388         parseCOFFModuleDefinition(*MB, LibMachine, /*MingwDef=*/false);
 389
 390     if (!Def) {
 391       llvm::errs() << "error parsing definition\n"
 392                    << errorToErrorCode(Def.takeError()).message();
 393       return 1;
 394     }
 395
 396     std::vector<COFFShortExport> NativeExports;
 397     std::string OutputFile = Def->OutputFile;
 398
 399     if (isArm64EC(LibMachine) && Args.hasArg(OPT_nativedeffile)) {
 400       std::unique_ptr<MemoryBuffer> NativeMB =
 401           openFile(Args.getLastArg(OPT_nativedeffile)->getValue());
 402       if (!NativeMB)
 403         return 1;
 404
 405       if (!NativeMB->getBufferSize()) {
 406         llvm::errs() << "native definition file empty\n";
 407         return 1;
 408       }
 409
 410       Expected<COFFModuleDefinition> NativeDef =
 411           parseCOFFModuleDefinition(*NativeMB, COFF::IMAGE_FILE_MACHINE_ARM64);
 412
 413       if (!NativeDef) {
 414         llvm::errs() << "error parsing native definition\n"
 415                      << errorToErrorCode(NativeDef.takeError()).message();
 416         return 1;
 417       }
 418       NativeExports = std::move(NativeDef->Exports);
 419       OutputFile = std::move(NativeDef->OutputFile);
 420     }
 421
 422     return writeImportLibrary(OutputFile, OutputPath, Def->Exports, LibMachine,
 423                               /*MinGW=*/false, NativeExports)
 424                ? 1
 425                : 0;
 426   }
 427
 428   // If no input files and not told otherwise, silently do nothing to match
 429   // lib.exe
 430   if (!Args.hasArgNoClaim(OPT_INPUT) && !Args.hasArg(OPT_llvmlibempty)) {
 431     if (!IgnoredWarnings.contains("emptyoutput")) {
 432       llvm::errs() << "warning: no input files, not writing output file\n";
 433       llvm::errs() << "         pass /llvmlibempty to write empty .lib file,\n";
 434       llvm::errs() << "         pass /ignore:emptyoutput to suppress warning\n";
 435       if (Args.hasFlag(OPT_WX, OPT_WX_no, false)) {
 436         llvm::errs() << "treating warning as error due to /WX\n";
 437         return 1;
 438       }
 439     }
 440     return 0;
 441   }
 442
 443   if (Args.hasArg(OPT_lst)) {
 444     doList(Args);
 445     return 0;
 446   }
 447
 448   std::vector<StringRef> SearchPaths = getSearchPaths(&Args, Saver);
 449
 450   std::vector<std::unique_ptr<MemoryBuffer>> MBs;
 451   StringSet<> Seen;
 452   std::vector<NewArchiveMember> Members;
 453
 454   // Create a NewArchiveMember for each input file.
 455   for (auto *Arg : Args.filtered(OPT_INPUT)) {
 456     // Find a file
 457     std::string Path = findInputFile(Arg->getValue(), SearchPaths);
 458     if (Path.empty()) {
 459       llvm::errs() << Arg->getValue() << ": no such file or directory\n";
 460       return 1;
 461     }
 462
 463     // Input files are uniquified by pathname. If you specify the exact same
 464     // path more than once, all but the first one are ignored.
 465     //
 466     // Note that there's a loophole in the rule; you can prepend `.\` or
 467     // something like that to a path to make it look different, and they are
 468     // handled as if they were different files. This behavior is compatible with
 469     // Microsoft lib.exe.
 470     if (!Seen.insert(Path).second)
 471       continue;
 472
 473     // Open a file.
 474     ErrorOr<std::unique_ptr<MemoryBuffer>> MOrErr = MemoryBuffer::getFile(
 475         Path, /*IsText=*/false, /*RequiresNullTerminator=*/false);
 476     fatalOpenError(errorCodeToError(MOrErr.getError()), Path);
 477     MemoryBufferRef MBRef = (*MOrErr)->getMemBufferRef();
 478
 479     // Append a file.
 480     appendFile(Members, LibMachine, LibMachineSource, MBRef);
 481
 482     // Take the ownership of the file buffer to keep the file open.
 483     MBs.push_back(std::move(*MOrErr));
 484   }
 485
 486   // Create an archive file.
 487   if (OutputPath.empty()) {
 488     if (!Members.empty()) {
 489       OutputPath = getDefaultOutputPath(Members[0]);
 490     } else {
 491       llvm::errs() << "no output path given, and cannot infer with no inputs\n";
 492       return 1;
 493     }
 494   }
 495   // llvm-lib uses relative paths for both regular and thin archives, unlike
 496   // standard GNU ar, which only uses relative paths for thin archives and
 497   // basenames for regular archives.
 498   for (NewArchiveMember &Member : Members) {
 499     if (sys::path::is_relative(Member.MemberName)) {
 500       Expected<std::string> PathOrErr =
 501           computeArchiveRelativePath(OutputPath, Member.MemberName);
 502       if (PathOrErr)
 503         Member.MemberName = Saver.save(*PathOrErr);
 504     }
 505   }
 506
 507   // For compatibility with MSVC, reverse member vector after de-duplication.
 508   std::reverse(Members.begin(), Members.end());
 509
 510   bool Thin = Args.hasArg(OPT_llvmlibthin);
 511   if (Error E = writeArchive(
 512           OutputPath, Members, SymtabWritingMode::NormalSymtab,
 513           Thin ? object::Archive::K_GNU : object::Archive::K_COFF,
 514           /*Deterministic=*/true, Thin, nullptr, COFF::isArm64EC(LibMachine))) {
 515     handleAllErrors(std::move(E), [&](const ErrorInfoBase &EI) {
 516       llvm::errs() << OutputPath << ": " << EI.message() << "\n";
 517     });
 518     return 1;
 519   }
 520
 521   return 0;
 522 }