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 "Buffer.h"
  11 #include "CopyConfig.h"
  12 #include "ELF/ELFObjcopy.h"
  13 #include "COFF/COFFObjcopy.h"
  14 #include "MachO/MachOObjcopy.h"
  15
  16 #include "llvm/ADT/STLExtras.h"
  17 #include "llvm/ADT/SmallVector.h"
  18 #include "llvm/ADT/StringRef.h"
  19 #include "llvm/ADT/Twine.h"
  20 #include "llvm/Object/Archive.h"
  21 #include "llvm/Object/ArchiveWriter.h"
  22 #include "llvm/Object/Binary.h"
  23 #include "llvm/Object/COFF.h"
  24 #include "llvm/Object/ELFObjectFile.h"
  25 #include "llvm/Object/ELFTypes.h"
  26 #include "llvm/Object/Error.h"
  27 #include "llvm/Object/MachO.h"
  28 #include "llvm/Option/Arg.h"
  29 #include "llvm/Option/ArgList.h"
  30 #include "llvm/Option/Option.h"
  31 #include "llvm/Support/Casting.h"
  32 #include "llvm/Support/Error.h"
  33 #include "llvm/Support/ErrorHandling.h"
  34 #include "llvm/Support/ErrorOr.h"
  35 #include "llvm/Support/InitLLVM.h"
  36 #include "llvm/Support/Memory.h"
  37 #include "llvm/Support/Path.h"
  38 #include "llvm/Support/Process.h"
  39 #include "llvm/Support/WithColor.h"
  40 #include "llvm/Support/raw_ostream.h"
  41 #include <algorithm>
  42 #include <cassert>
  43 #include <cstdlib>
  44 #include <memory>
  45 #include <string>
  46 #include <system_error>
  47 #include <utility>
  48
  49 namespace llvm {
  50 namespace objcopy {
  51
  52 // The name this program was invoked as.
  53 StringRef ToolName;
  54
  55 LLVM_ATTRIBUTE_NORETURN void error(Twine Message) {
  56   WithColor::error(errs(), ToolName) << Message << "\n";
  57   exit(1);
  58 }
  59
  60 LLVM_ATTRIBUTE_NORETURN void error(Error E) {
  61   assert(E);
  62   std::string Buf;
  63   raw_string_ostream OS(Buf);
  64   logAllUnhandledErrors(std::move(E), OS);
  65   OS.flush();
  66   WithColor::error(errs(), ToolName) << Buf;
  67   exit(1);
  68 }
  69
  70 LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, std::error_code EC) {
  71   assert(EC);
  72   error(createFileError(File, EC));
  73 }
  74
  75 LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, Error E) {
  76   assert(E);
  77   std::string Buf;
  78   raw_string_ostream OS(Buf);
  79   logAllUnhandledErrors(std::move(E), OS);
  80   OS.flush();
  81   WithColor::error(errs(), ToolName) << "'" << File << "': " << Buf;
  82   exit(1);
  83 }
  84
  85 ErrorSuccess reportWarning(Error E) {
  86   assert(E);
  87   WithColor::warning(errs(), ToolName) << toString(std::move(E)) << '\n';
  88   return Error::success();
  89 }
  90
  91 } // end namespace objcopy
  92 } // end namespace llvm
  93
  94 using namespace llvm;
  95 using namespace llvm::object;
  96 using namespace llvm::objcopy;
  97
  98 // For regular archives this function simply calls llvm::writeArchive,
  99 // For thin archives it writes the archive file itself as well as its members.
 100 static Error deepWriteArchive(StringRef ArcName,
 101                               ArrayRef<NewArchiveMember> NewMembers,
 102                               bool WriteSymtab, object::Archive::Kind Kind,
 103                               bool Deterministic, bool Thin) {
 104   if (Error E = writeArchive(ArcName, NewMembers, WriteSymtab, Kind,
 105                              Deterministic, Thin))
 106     return createFileError(ArcName, std::move(E));
 107
 108   if (!Thin)
 109     return Error::success();
 110
 111   for (const NewArchiveMember &Member : NewMembers) {
 112     // Internally, FileBuffer will use the buffer created by
 113     // FileOutputBuffer::create, for regular files (that is the case for
 114     // deepWriteArchive) 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     FileBuffer FB(Member.MemberName);
 121     if (Error E = FB.allocate(Member.Buf->getBufferSize()))
 122       return E;
 123     std::copy(Member.Buf->getBufferStart(), Member.Buf->getBufferEnd(),
 124               FB.getBufferStart());
 125     if (Error E = FB.commit())
 126       return E;
 127   }
 128   return Error::success();
 129 }
 130
 131 /// The function executeObjcopyOnIHex does the dispatch based on the format
 132 /// of the output specified by the command line options.
 133 static Error executeObjcopyOnIHex(const CopyConfig &Config, MemoryBuffer &In,
 134                                   Buffer &Out) {
 135   // TODO: support output formats other than ELF.
 136   return elf::executeObjcopyOnIHex(Config, In, Out);
 137 }
 138
 139 /// The function executeObjcopyOnRawBinary does the dispatch based on the format
 140 /// of the output specified by the command line options.
 141 static Error executeObjcopyOnRawBinary(const CopyConfig &Config,
 142                                        MemoryBuffer &In, Buffer &Out) {
 143   switch (Config.OutputFormat) {
 144   case FileFormat::ELF:
 145   // FIXME: Currently, we call elf::executeObjcopyOnRawBinary even if the
 146   // output format is binary/ihex or it's not given. This behavior differs from
 147   // GNU objcopy. See https://bugs.llvm.org/show_bug.cgi?id=42171 for details.
 148   case FileFormat::Binary:
 149   case FileFormat::IHex:
 150   case FileFormat::Unspecified:
 151     return elf::executeObjcopyOnRawBinary(Config, In, Out);
 152   }
 153
 154   llvm_unreachable("unsupported output format");
 155 }
 156
 157 /// The function executeObjcopyOnBinary does the dispatch based on the format
 158 /// of the input binary (ELF, MachO or COFF).
 159 static Error executeObjcopyOnBinary(const CopyConfig &Config,
 160                                     object::Binary &In, Buffer &Out) {
 161   if (auto *ELFBinary = dyn_cast<object::ELFObjectFileBase>(&In))
 162     return elf::executeObjcopyOnBinary(Config, *ELFBinary, Out);
 163   else if (auto *COFFBinary = dyn_cast<object::COFFObjectFile>(&In))
 164     return coff::executeObjcopyOnBinary(Config, *COFFBinary, Out);
 165   else if (auto *MachOBinary = dyn_cast<object::MachOObjectFile>(&In))
 166     return macho::executeObjcopyOnBinary(Config, *MachOBinary, Out);
 167   else
 168     return createStringError(object_error::invalid_file_type,
 169                              "unsupported object file format");
 170 }
 171
 172 static Error executeObjcopyOnArchive(const CopyConfig &Config,
 173                                      const Archive &Ar) {
 174   std::vector<NewArchiveMember> NewArchiveMembers;
 175   Error Err = Error::success();
 176   for (const Archive::Child &Child : Ar.children(Err)) {
 177     Expected<StringRef> ChildNameOrErr = Child.getName();
 178     if (!ChildNameOrErr)
 179       return createFileError(Ar.getFileName(), ChildNameOrErr.takeError());
 180
 181     Expected<std::unique_ptr<Binary>> ChildOrErr = Child.getAsBinary();
 182     if (!ChildOrErr)
 183       return createFileError(Ar.getFileName() + "(" + *ChildNameOrErr + ")",
 184                              ChildOrErr.takeError());
 185
 186     MemBuffer MB(ChildNameOrErr.get());
 187     if (Error E = executeObjcopyOnBinary(Config, *ChildOrErr->get(), MB))
 188       return E;
 189
 190     Expected<NewArchiveMember> Member =
 191         NewArchiveMember::getOldMember(Child, Config.DeterministicArchives);
 192     if (!Member)
 193       return createFileError(Ar.getFileName(), Member.takeError());
 194     Member->Buf = MB.releaseMemoryBuffer();
 195     Member->MemberName = Member->Buf->getBufferIdentifier();
 196     NewArchiveMembers.push_back(std::move(*Member));
 197   }
 198   if (Err)
 199     return createFileError(Config.InputFilename, std::move(Err));
 200
 201   return deepWriteArchive(Config.OutputFilename, NewArchiveMembers,
 202                           Ar.hasSymbolTable(), Ar.kind(),
 203                           Config.DeterministicArchives, Ar.isThin());
 204 }
 205
 206 static Error restoreStatOnFile(StringRef Filename,
 207                                const sys::fs::file_status &Stat,
 208                                bool PreserveDates) {
 209   int FD;
 210
 211   // Writing to stdout should not be treated as an error here, just
 212   // do not set access/modification times or permissions.
 213   if (Filename == "-")
 214     return Error::success();
 215
 216   if (auto EC =
 217           sys::fs::openFileForWrite(Filename, FD, sys::fs::CD_OpenExisting))
 218     return createFileError(Filename, EC);
 219
 220   if (PreserveDates)
 221     if (auto EC = sys::fs::setLastAccessAndModificationTime(
 222             FD, Stat.getLastAccessedTime(), Stat.getLastModificationTime()))
 223       return createFileError(Filename, EC);
 224
 225   sys::fs::file_status OStat;
 226   if (std::error_code EC = sys::fs::status(FD, OStat))
 227     return createFileError(Filename, EC);
 228   if (OStat.type() == sys::fs::file_type::regular_file)
 229 #ifdef _WIN32
 230     if (auto EC = sys::fs::setPermissions(
 231             Filename, static_cast<sys::fs::perms>(Stat.permissions() &
 232                                                   ~sys::fs::getUmask())))
 233 #else
 234     if (auto EC = sys::fs::setPermissions(
 235             FD, static_cast<sys::fs::perms>(Stat.permissions() &
 236                                             ~sys::fs::getUmask())))
 237 #endif
 238       return createFileError(Filename, EC);
 239
 240   if (auto EC = sys::Process::SafelyCloseFileDescriptor(FD))
 241     return createFileError(Filename, EC);
 242
 243   return Error::success();
 244 }
 245
 246 /// The function executeObjcopy does the higher level dispatch based on the type
 247 /// of input (raw binary, archive or single object file) and takes care of the
 248 /// format-agnostic modifications, i.e. preserving dates.
 249 static Error executeObjcopy(const CopyConfig &Config) {
 250   sys::fs::file_status Stat;
 251   if (Config.InputFilename != "-") {
 252     if (auto EC = sys::fs::status(Config.InputFilename, Stat))
 253       return createFileError(Config.InputFilename, EC);
 254   } else {
 255     Stat.permissions(static_cast<sys::fs::perms>(0777));
 256   }
 257
 258   typedef Error (*ProcessRawFn)(const CopyConfig &, MemoryBuffer &, Buffer &);
 259   ProcessRawFn ProcessRaw;
 260   switch (Config.InputFormat) {
 261   case FileFormat::Binary:
 262     ProcessRaw = executeObjcopyOnRawBinary;
 263     break;
 264   case FileFormat::IHex:
 265     ProcessRaw = executeObjcopyOnIHex;
 266     break;
 267   default:
 268     ProcessRaw = nullptr;
 269   }
 270
 271   if (ProcessRaw) {
 272     auto BufOrErr = MemoryBuffer::getFileOrSTDIN(Config.InputFilename);
 273     if (!BufOrErr)
 274       return createFileError(Config.InputFilename, BufOrErr.getError());
 275     FileBuffer FB(Config.OutputFilename);
 276     if (Error E = ProcessRaw(Config, *BufOrErr->get(), FB))
 277       return E;
 278   } else {
 279     Expected<OwningBinary<llvm::object::Binary>> BinaryOrErr =
 280         createBinary(Config.InputFilename);
 281     if (!BinaryOrErr)
 282       return createFileError(Config.InputFilename, BinaryOrErr.takeError());
 283
 284     if (Archive *Ar = dyn_cast<Archive>(BinaryOrErr.get().getBinary())) {
 285       if (Error E = executeObjcopyOnArchive(Config, *Ar))
 286         return E;
 287     } else {
 288       FileBuffer FB(Config.OutputFilename);
 289       if (Error E = executeObjcopyOnBinary(Config,
 290                                            *BinaryOrErr.get().getBinary(), FB))
 291         return E;
 292     }
 293   }
 294
 295   if (Error E =
 296           restoreStatOnFile(Config.OutputFilename, Stat, Config.PreserveDates))
 297     return E;
 298
 299   if (!Config.SplitDWO.empty()) {
 300     Stat.permissions(static_cast<sys::fs::perms>(0666));
 301     if (Error E =
 302             restoreStatOnFile(Config.SplitDWO, Stat, Config.PreserveDates))
 303       return E;
 304   }
 305
 306   return Error::success();
 307 }
 308
 309 int main(int argc, char **argv) {
 310   InitLLVM X(argc, argv);
 311   ToolName = argv[0];
 312   bool IsStrip = sys::path::stem(ToolName).contains("strip");
 313   Expected<DriverConfig> DriverConfig =
 314       IsStrip ? parseStripOptions(makeArrayRef(argv + 1, argc), reportWarning)
 315               : parseObjcopyOptions(makeArrayRef(argv + 1, argc));
 316   if (!DriverConfig) {
 317     logAllUnhandledErrors(DriverConfig.takeError(),
 318                           WithColor::error(errs(), ToolName));
 319     return 1;
 320   }
 321   for (const CopyConfig &CopyConfig : DriverConfig->CopyConfigs) {
 322     if (Error E = executeObjcopy(CopyConfig)) {
 323       logAllUnhandledErrors(std::move(E), WithColor::error(errs(), ToolName));
 324       return 1;
 325     }
 326   }
 327
 328   return 0;
 329 }