llvm/tools/llvm-objcopy/llvm-objcopy.cpp

   1 //===- llvm-objcopy.cpp ---------------------------------------------------===//
   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 #include "llvm-objcopy.h"
  10 #include "COFF/COFFConfig.h"
  11 #include "COFF/COFFObjcopy.h"
  12 #include "CommonConfig.h"
  13 #include "ConfigManager.h"
  14 #include "ELF/ELFConfig.h"
  15 #include "ELF/ELFObjcopy.h"
  16 #include "MachO/MachOConfig.h"
  17 #include "MachO/MachOObjcopy.h"
  18 #include "wasm/WasmConfig.h"
  19 #include "wasm/WasmObjcopy.h"
  20
  21 #include "llvm/ADT/STLExtras.h"
  22 #include "llvm/ADT/SmallVector.h"
  23 #include "llvm/ADT/StringRef.h"
  24 #include "llvm/ADT/Twine.h"
  25 #include "llvm/BinaryFormat/ELF.h"
  26 #include "llvm/Object/Archive.h"
  27 #include "llvm/Object/ArchiveWriter.h"
  28 #include "llvm/Object/Binary.h"
  29 #include "llvm/Object/COFF.h"
  30 #include "llvm/Object/ELFObjectFile.h"
  31 #include "llvm/Object/ELFTypes.h"
  32 #include "llvm/Object/Error.h"
  33 #include "llvm/Object/MachO.h"
  34 #include "llvm/Object/MachOUniversal.h"
  35 #include "llvm/Object/Wasm.h"
  36 #include "llvm/Option/Arg.h"
  37 #include "llvm/Option/ArgList.h"
  38 #include "llvm/Option/Option.h"
  39 #include "llvm/Support/Casting.h"
  40 #include "llvm/Support/CommandLine.h"
  41 #include "llvm/Support/Errc.h"
  42 #include "llvm/Support/Error.h"
  43 #include "llvm/Support/ErrorHandling.h"
  44 #include "llvm/Support/ErrorOr.h"
  45 #include "llvm/Support/Host.h"
  46 #include "llvm/Support/InitLLVM.h"
  47 #include "llvm/Support/Memory.h"
  48 #include "llvm/Support/Path.h"
  49 #include "llvm/Support/Process.h"
  50 #include "llvm/Support/SmallVectorMemoryBuffer.h"
  51 #include "llvm/Support/StringSaver.h"
  52 #include "llvm/Support/WithColor.h"
  53 #include "llvm/Support/raw_ostream.h"
  54 #include <algorithm>
  55 #include <cassert>
  56 #include <cstdlib>
  57 #include <memory>
  58 #include <string>
  59 #include <system_error>
  60 #include <utility>
  61
  62 using namespace llvm;
  63 using namespace llvm::objcopy;
  64 using namespace llvm::object;
  65
  66 // The name this program was invoked as.
  67 static StringRef ToolName;
  68
  69 static ErrorSuccess reportWarning(Error E) {
  70   assert(E);
  71   WithColor::warning(errs(), ToolName) << toString(std::move(E)) << '\n';
  72   return Error::success();
  73 }
  74
  75 static Expected<DriverConfig> getDriverConfig(ArrayRef<const char *> Args) {
  76   StringRef Stem = sys::path::stem(ToolName);
  77   auto Is = [=](StringRef Tool) {
  78     // We need to recognize the following filenames:
  79     //
  80     // llvm-objcopy -> objcopy
  81     // strip-10.exe -> strip
  82     // powerpc64-unknown-freebsd13-objcopy -> objcopy
  83     // llvm-install-name-tool -> install-name-tool
  84     auto I = Stem.rfind_insensitive(Tool);
  85     return I != StringRef::npos &&
  86            (I + Tool.size() == Stem.size() || !isAlnum(Stem[I + Tool.size()]));
  87   };
  88
  89   if (Is("bitcode-strip") || Is("bitcode_strip"))
  90     return parseBitcodeStripOptions(Args);
  91   else if (Is("strip"))
  92     return parseStripOptions(Args, reportWarning);
  93   else if (Is("install-name-tool") || Is("install_name_tool"))
  94     return parseInstallNameToolOptions(Args);
  95   else
  96     return parseObjcopyOptions(Args, reportWarning);
  97 }
  98
  99 // For regular archives this function simply calls llvm::writeArchive,
 100 // For thin archives it writes the archive file itself as well as its members.
 101 static Error deepWriteArchive(StringRef ArcName,
 102                               ArrayRef<NewArchiveMember> NewMembers,
 103                               bool WriteSymtab, object::Archive::Kind Kind,
 104                               bool Deterministic, bool Thin) {
 105   if (Error E = writeArchive(ArcName, NewMembers, WriteSymtab, Kind,
 106                              Deterministic, Thin))
 107     return createFileError(ArcName, std::move(E));
 108
 109   if (!Thin)
 110     return Error::success();
 111
 112   for (const NewArchiveMember &Member : NewMembers) {
 113     // For regular files (as is the case for deepWriteArchive),
 114     // FileOutputBuffer::create will return OnDiskBuffer.
 115     // OnDiskBuffer uses a temporary file and then renames it. So in reality
 116     // there is no inefficiency / duplicated in-memory buffers in this case. For
 117     // now in-memory buffers can not be completely avoided since
 118     // NewArchiveMember still requires them even though writeArchive does not
 119     // write them on disk.
 120     Expected<std::unique_ptr<FileOutputBuffer>> FB =
 121         FileOutputBuffer::create(Member.MemberName, Member.Buf->getBufferSize(),
 122                                  FileOutputBuffer::F_executable);
 123     if (!FB)
 124       return FB.takeError();
 125     std::copy(Member.Buf->getBufferStart(), Member.Buf->getBufferEnd(),
 126               (*FB)->getBufferStart());
 127     if (Error E = (*FB)->commit())
 128       return E;
 129   }
 130   return Error::success();
 131 }
 132
 133 /// The function executeObjcopyOnIHex does the dispatch based on the format
 134 /// of the output specified by the command line options.
 135 static Error executeObjcopyOnIHex(ConfigManager &ConfigMgr, MemoryBuffer &In,
 136                                   raw_ostream &Out) {
 137   // TODO: support output formats other than ELF.
 138   Expected<const ELFConfig &> ELFConfig = ConfigMgr.getELFConfig();
 139   if (!ELFConfig)
 140     return ELFConfig.takeError();
 141
 142   return elf::executeObjcopyOnIHex(ConfigMgr.getCommonConfig(), *ELFConfig, In,
 143                                    Out);
 144 }
 145
 146 /// The function executeObjcopyOnRawBinary does the dispatch based on the format
 147 /// of the output specified by the command line options.
 148 static Error executeObjcopyOnRawBinary(ConfigManager &ConfigMgr,
 149                                        MemoryBuffer &In, raw_ostream &Out) {
 150   const CommonConfig &Config = ConfigMgr.getCommonConfig();
 151   switch (Config.OutputFormat) {
 152   case FileFormat::ELF:
 153   // FIXME: Currently, we call elf::executeObjcopyOnRawBinary even if the
 154   // output format is binary/ihex or it's not given. This behavior differs from
 155   // GNU objcopy. See https://bugs.llvm.org/show_bug.cgi?id=42171 for details.
 156   case FileFormat::Binary:
 157   case FileFormat::IHex:
 158   case FileFormat::Unspecified:
 159     Expected<const ELFConfig &> ELFConfig = ConfigMgr.getELFConfig();
 160     if (!ELFConfig)
 161       return ELFConfig.takeError();
 162
 163     return elf::executeObjcopyOnRawBinary(Config, *ELFConfig, In, Out);
 164   }
 165
 166   llvm_unreachable("unsupported output format");
 167 }
 168
 169 /// The function executeObjcopyOnBinary does the dispatch based on the format
 170 /// of the input binary (ELF, MachO or COFF).
 171 static Error executeObjcopyOnBinary(const MultiFormatConfig &Config,
 172                                     object::Binary &In, raw_ostream &Out) {
 173   if (auto *ELFBinary = dyn_cast<object::ELFObjectFileBase>(&In)) {
 174     Expected<const ELFConfig &> ELFConfig = Config.getELFConfig();
 175     if (!ELFConfig)
 176       return ELFConfig.takeError();
 177
 178     return elf::executeObjcopyOnBinary(Config.getCommonConfig(), *ELFConfig,
 179                                        *ELFBinary, Out);
 180   } else if (auto *COFFBinary = dyn_cast<object::COFFObjectFile>(&In)) {
 181     Expected<const COFFConfig &> COFFConfig = Config.getCOFFConfig();
 182     if (!COFFConfig)
 183       return COFFConfig.takeError();
 184
 185     return coff::executeObjcopyOnBinary(Config.getCommonConfig(), *COFFConfig,
 186                                         *COFFBinary, Out);
 187   } else if (auto *MachOBinary = dyn_cast<object::MachOObjectFile>(&In)) {
 188     Expected<const MachOConfig &> MachOConfig = Config.getMachOConfig();
 189     if (!MachOConfig)
 190       return MachOConfig.takeError();
 191
 192     return macho::executeObjcopyOnBinary(Config.getCommonConfig(), *MachOConfig,
 193                                          *MachOBinary, Out);
 194   } else if (auto *MachOUniversalBinary =
 195                  dyn_cast<object::MachOUniversalBinary>(&In)) {
 196     return macho::executeObjcopyOnMachOUniversalBinary(
 197         Config, *MachOUniversalBinary, Out);
 198   } else if (auto *WasmBinary = dyn_cast<object::WasmObjectFile>(&In)) {
 199     Expected<const WasmConfig &> WasmConfig = Config.getWasmConfig();
 200     if (!WasmConfig)
 201       return WasmConfig.takeError();
 202
 203     return objcopy::wasm::executeObjcopyOnBinary(Config.getCommonConfig(),
 204                                                  *WasmConfig, *WasmBinary, Out);
 205   } else
 206     return createStringError(object_error::invalid_file_type,
 207                              "unsupported object file format");
 208 }
 209
 210 namespace llvm {
 211 namespace objcopy {
 212
 213 Expected<std::vector<NewArchiveMember>>
 214 createNewArchiveMembers(const MultiFormatConfig &Config, const Archive &Ar) {
 215   std::vector<NewArchiveMember> NewArchiveMembers;
 216   Error Err = Error::success();
 217   for (const Archive::Child &Child : Ar.children(Err)) {
 218     Expected<StringRef> ChildNameOrErr = Child.getName();
 219     if (!ChildNameOrErr)
 220       return createFileError(Ar.getFileName(), ChildNameOrErr.takeError());
 221
 222     Expected<std::unique_ptr<Binary>> ChildOrErr = Child.getAsBinary();
 223     if (!ChildOrErr)
 224       return createFileError(Ar.getFileName() + "(" + *ChildNameOrErr + ")",
 225                              ChildOrErr.takeError());
 226
 227     SmallVector<char, 0> Buffer;
 228     raw_svector_ostream MemStream(Buffer);
 229
 230     if (Error E = executeObjcopyOnBinary(Config, *ChildOrErr->get(), MemStream))
 231       return std::move(E);
 232
 233     Expected<NewArchiveMember> Member = NewArchiveMember::getOldMember(
 234         Child, Config.getCommonConfig().DeterministicArchives);
 235     if (!Member)
 236       return createFileError(Ar.getFileName(), Member.takeError());
 237
 238     Member->Buf = std::make_unique<SmallVectorMemoryBuffer>(
 239         std::move(Buffer), ChildNameOrErr.get(),
 240         /*RequiresNullTerminator=*/false);
 241     Member->MemberName = Member->Buf->getBufferIdentifier();
 242     NewArchiveMembers.push_back(std::move(*Member));
 243   }
 244   if (Err)
 245     return createFileError(Config.getCommonConfig().InputFilename,
 246                            std::move(Err));
 247   return std::move(NewArchiveMembers);
 248 }
 249
 250 } // end namespace objcopy
 251 } // end namespace llvm
 252
 253 static Error executeObjcopyOnArchive(const ConfigManager &ConfigMgr,
 254                                      const object::Archive &Ar) {
 255   Expected<std::vector<NewArchiveMember>> NewArchiveMembersOrErr =
 256       createNewArchiveMembers(ConfigMgr, Ar);
 257   if (!NewArchiveMembersOrErr)
 258     return NewArchiveMembersOrErr.takeError();
 259   const CommonConfig &Config = ConfigMgr.getCommonConfig();
 260   return deepWriteArchive(Config.OutputFilename, *NewArchiveMembersOrErr,
 261                           Ar.hasSymbolTable(), Ar.kind(),
 262                           Config.DeterministicArchives, Ar.isThin());
 263 }
 264
 265 static Error restoreStatOnFile(StringRef Filename,
 266                                const sys::fs::file_status &Stat,
 267                                const ConfigManager &ConfigMgr) {
 268   int FD;
 269   const CommonConfig &Config = ConfigMgr.getCommonConfig();
 270
 271   // Writing to stdout should not be treated as an error here, just
 272   // do not set access/modification times or permissions.
 273   if (Filename == "-")
 274     return Error::success();
 275
 276   if (auto EC =
 277           sys::fs::openFileForWrite(Filename, FD, sys::fs::CD_OpenExisting))
 278     return createFileError(Filename, EC);
 279
 280   if (Config.PreserveDates)
 281     if (auto EC = sys::fs::setLastAccessAndModificationTime(
 282             FD, Stat.getLastAccessedTime(), Stat.getLastModificationTime()))
 283       return createFileError(Filename, EC);
 284
 285   sys::fs::file_status OStat;
 286   if (std::error_code EC = sys::fs::status(FD, OStat))
 287     return createFileError(Filename, EC);
 288   if (OStat.type() == sys::fs::file_type::regular_file) {
 289 #ifndef _WIN32
 290     // Keep ownership if llvm-objcopy is called under root.
 291     if (Config.InputFilename == Config.OutputFilename && OStat.getUser() == 0)
 292       sys::fs::changeFileOwnership(FD, Stat.getUser(), Stat.getGroup());
 293 #endif
 294
 295     sys::fs::perms Perm = Stat.permissions();
 296     if (Config.InputFilename != Config.OutputFilename)
 297       Perm = static_cast<sys::fs::perms>(Perm & ~sys::fs::getUmask() & ~06000);
 298 #ifdef _WIN32
 299     if (auto EC = sys::fs::setPermissions(Filename, Perm))
 300 #else
 301     if (auto EC = sys::fs::setPermissions(FD, Perm))
 302 #endif
 303       return createFileError(Filename, EC);
 304   }
 305
 306   if (auto EC = sys::Process::SafelyCloseFileDescriptor(FD))
 307     return createFileError(Filename, EC);
 308
 309   return Error::success();
 310 }
 311
 312 /// The function executeObjcopy does the higher level dispatch based on the type
 313 /// of input (raw binary, archive or single object file) and takes care of the
 314 /// format-agnostic modifications, i.e. preserving dates.
 315 static Error executeObjcopy(ConfigManager &ConfigMgr) {
 316   CommonConfig &Config = ConfigMgr.Common;
 317
 318   sys::fs::file_status Stat;
 319   if (Config.InputFilename != "-") {
 320     if (auto EC = sys::fs::status(Config.InputFilename, Stat))
 321       return createFileError(Config.InputFilename, EC);
 322   } else {
 323     Stat.permissions(static_cast<sys::fs::perms>(0777));
 324   }
 325
 326   std::function<Error(raw_ostream & OutFile)> ObjcopyFunc;
 327
 328   OwningBinary<llvm::object::Binary> BinaryHolder;
 329   std::unique_ptr<MemoryBuffer> MemoryBufferHolder;
 330
 331   if (Config.InputFormat == FileFormat::Binary ||
 332       Config.InputFormat == FileFormat::IHex) {
 333     ErrorOr<std::unique_ptr<MemoryBuffer>> BufOrErr =
 334         MemoryBuffer::getFileOrSTDIN(Config.InputFilename);
 335     if (!BufOrErr)
 336       return createFileError(Config.InputFilename, BufOrErr.getError());
 337     MemoryBufferHolder = std::move(*BufOrErr);
 338
 339     if (Config.InputFormat == FileFormat::Binary)
 340       ObjcopyFunc = [&](raw_ostream &OutFile) -> Error {
 341         // Handle FileFormat::Binary.
 342         return executeObjcopyOnRawBinary(ConfigMgr, *MemoryBufferHolder,
 343                                          OutFile);
 344       };
 345     else
 346       ObjcopyFunc = [&](raw_ostream &OutFile) -> Error {
 347         // Handle FileFormat::IHex.
 348         return executeObjcopyOnIHex(ConfigMgr, *MemoryBufferHolder, OutFile);
 349       };
 350   } else {
 351     Expected<OwningBinary<llvm::object::Binary>> BinaryOrErr =
 352         createBinary(Config.InputFilename);
 353     if (!BinaryOrErr)
 354       return createFileError(Config.InputFilename, BinaryOrErr.takeError());
 355     BinaryHolder = std::move(*BinaryOrErr);
 356
 357     if (Archive *Ar = dyn_cast<Archive>(BinaryHolder.getBinary())) {
 358       // Handle Archive.
 359       if (Error E = executeObjcopyOnArchive(ConfigMgr, *Ar))
 360         return E;
 361     } else {
 362       // Handle llvm::object::Binary.
 363       ObjcopyFunc = [&](raw_ostream &OutFile) -> Error {
 364         return executeObjcopyOnBinary(ConfigMgr, *BinaryHolder.getBinary(),
 365                                       OutFile);
 366       };
 367     }
 368   }
 369
 370   if (ObjcopyFunc) {
 371     if (Config.SplitDWO.empty()) {
 372       // Apply transformations described by Config and store result into
 373       // Config.OutputFilename using specified ObjcopyFunc function.
 374       if (Error E = writeToOutput(Config.OutputFilename, ObjcopyFunc))
 375         return E;
 376     } else {
 377       Config.ExtractDWO = true;
 378       Config.StripDWO = false;
 379       // Copy .dwo tables from the Config.InputFilename into Config.SplitDWO
 380       // file using specified ObjcopyFunc function.
 381       if (Error E = writeToOutput(Config.SplitDWO, ObjcopyFunc))
 382         return E;
 383       Config.ExtractDWO = false;
 384       Config.StripDWO = true;
 385       // Apply transformations described by Config, remove .dwo tables and
 386       // store result into Config.OutputFilename using specified ObjcopyFunc
 387       // function.
 388       if (Error E = writeToOutput(Config.OutputFilename, ObjcopyFunc))
 389         return E;
 390     }
 391   }
 392
 393   if (Error E = restoreStatOnFile(Config.OutputFilename, Stat, ConfigMgr))
 394     return E;
 395
 396   if (!Config.SplitDWO.empty()) {
 397     Stat.permissions(static_cast<sys::fs::perms>(0666));
 398     if (Error E = restoreStatOnFile(Config.SplitDWO, Stat, ConfigMgr))
 399       return E;
 400   }
 401
 402   return Error::success();
 403 }
 404
 405 int main(int argc, char **argv) {
 406   InitLLVM X(argc, argv);
 407   ToolName = argv[0];
 408
 409   // Expand response files.
 410   // TODO: Move these lines, which are copied from lib/Support/CommandLine.cpp,
 411   // into a separate function in the CommandLine library and call that function
 412   // here. This is duplicated code.
 413   SmallVector<const char *, 20> NewArgv(argv, argv + argc);
 414   BumpPtrAllocator A;
 415   StringSaver Saver(A);
 416   cl::ExpandResponseFiles(Saver,
 417                           Triple(sys::getProcessTriple()).isOSWindows()
 418                               ? cl::TokenizeWindowsCommandLine
 419                               : cl::TokenizeGNUCommandLine,
 420                           NewArgv);
 421
 422   auto Args = makeArrayRef(NewArgv).drop_front();
 423   Expected<DriverConfig> DriverConfig = getDriverConfig(Args);
 424
 425   if (!DriverConfig) {
 426     logAllUnhandledErrors(DriverConfig.takeError(),
 427                           WithColor::error(errs(), ToolName));
 428     return 1;
 429   }
 430   for (ConfigManager &ConfigMgr : DriverConfig->CopyConfigs) {
 431     if (Error E = executeObjcopy(ConfigMgr)) {
 432       logAllUnhandledErrors(std::move(E), WithColor::error(errs(), ToolName));
 433       return 1;
 434     }
 435   }
 436
 437   return 0;
 438 }