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/CommandLine.h"
  33 #include "llvm/Support/Error.h"
  34 #include "llvm/Support/ErrorHandling.h"
  35 #include "llvm/Support/ErrorOr.h"
  36 #include "llvm/Support/InitLLVM.h"
  37 #include "llvm/Support/Memory.h"
  38 #include "llvm/Support/Path.h"
  39 #include "llvm/Support/Process.h"
  40 #include "llvm/Support/StringSaver.h"
  41 #include "llvm/Support/WithColor.h"
  42 #include "llvm/Support/raw_ostream.h"
  43 #include <algorithm>
  44 #include <cassert>
  45 #include <cstdlib>
  46 #include <memory>
  47 #include <string>
  48 #include <system_error>
  49 #include <utility>
  50
  51 namespace llvm {
  52 namespace objcopy {
  53
  54 // The name this program was invoked as.
  55 StringRef ToolName;
  56
  57 LLVM_ATTRIBUTE_NORETURN void error(Twine Message) {
  58   WithColor::error(errs(), ToolName) << Message << "\n";
  59   exit(1);
  60 }
  61
  62 LLVM_ATTRIBUTE_NORETURN void error(Error E) {
  63   assert(E);
  64   std::string Buf;
  65   raw_string_ostream OS(Buf);
  66   logAllUnhandledErrors(std::move(E), OS);
  67   OS.flush();
  68   WithColor::error(errs(), ToolName) << Buf;
  69   exit(1);
  70 }
  71
  72 LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, std::error_code EC) {
  73   assert(EC);
  74   error(createFileError(File, EC));
  75 }
  76
  77 LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, Error E) {
  78   assert(E);
  79   std::string Buf;
  80   raw_string_ostream OS(Buf);
  81   logAllUnhandledErrors(std::move(E), OS);
  82   OS.flush();
  83   WithColor::error(errs(), ToolName) << "'" << File << "': " << Buf;
  84   exit(1);
  85 }
  86
  87 ErrorSuccess reportWarning(Error E) {
  88   assert(E);
  89   WithColor::warning(errs(), ToolName) << toString(std::move(E)) << '\n';
  90   return Error::success();
  91 }
  92
  93 } // end namespace objcopy
  94 } // end namespace llvm
  95
  96 using namespace llvm;
  97 using namespace llvm::object;
  98 using namespace llvm::objcopy;
  99
 100 // For regular archives this function simply calls llvm::writeArchive,
 101 // For thin archives it writes the archive file itself as well as its members.
 102 static Error deepWriteArchive(StringRef ArcName,
 103                               ArrayRef<NewArchiveMember> NewMembers,
 104                               bool WriteSymtab, object::Archive::Kind Kind,
 105                               bool Deterministic, bool Thin) {
 106   if (Error E = writeArchive(ArcName, NewMembers, WriteSymtab, Kind,
 107                              Deterministic, Thin))
 108     return createFileError(ArcName, std::move(E));
 109
 110   if (!Thin)
 111     return Error::success();
 112
 113   for (const NewArchiveMember &Member : NewMembers) {
 114     // Internally, FileBuffer will use the buffer created by
 115     // FileOutputBuffer::create, for regular files (that is the case for
 116     // deepWriteArchive) FileOutputBuffer::create will return OnDiskBuffer.
 117     // OnDiskBuffer uses a temporary file and then renames it. So in reality
 118     // there is no inefficiency / duplicated in-memory buffers in this case. For
 119     // now in-memory buffers can not be completely avoided since
 120     // NewArchiveMember still requires them even though writeArchive does not
 121     // write them on disk.
 122     FileBuffer FB(Member.MemberName);
 123     if (Error E = FB.allocate(Member.Buf->getBufferSize()))
 124       return E;
 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(CopyConfig &Config, MemoryBuffer &In,
 136                                   Buffer &Out) {
 137   // TODO: support output formats other than ELF.
 138   if (Error E = Config.parseELFConfig())
 139     return E;
 140   return elf::executeObjcopyOnIHex(Config, In, Out);
 141 }
 142
 143 /// The function executeObjcopyOnRawBinary does the dispatch based on the format
 144 /// of the output specified by the command line options.
 145 static Error executeObjcopyOnRawBinary(CopyConfig &Config, MemoryBuffer &In,
 146                                        Buffer &Out) {
 147   switch (Config.OutputFormat) {
 148   case FileFormat::ELF:
 149   // FIXME: Currently, we call elf::executeObjcopyOnRawBinary even if the
 150   // output format is binary/ihex or it's not given. This behavior differs from
 151   // GNU objcopy. See https://bugs.llvm.org/show_bug.cgi?id=42171 for details.
 152   case FileFormat::Binary:
 153   case FileFormat::IHex:
 154   case FileFormat::Unspecified:
 155     if (Error E = Config.parseELFConfig())
 156       return E;
 157     return elf::executeObjcopyOnRawBinary(Config, In, Out);
 158   }
 159
 160   llvm_unreachable("unsupported output format");
 161 }
 162
 163 /// The function executeObjcopyOnBinary does the dispatch based on the format
 164 /// of the input binary (ELF, MachO or COFF).
 165 static Error executeObjcopyOnBinary(CopyConfig &Config, object::Binary &In,
 166                                     Buffer &Out) {
 167   if (auto *ELFBinary = dyn_cast<object::ELFObjectFileBase>(&In)) {
 168     if (Error E = Config.parseELFConfig())
 169       return E;
 170     return elf::executeObjcopyOnBinary(Config, *ELFBinary, Out);
 171   } else if (auto *COFFBinary = dyn_cast<object::COFFObjectFile>(&In))
 172     return coff::executeObjcopyOnBinary(Config, *COFFBinary, Out);
 173   else if (auto *MachOBinary = dyn_cast<object::MachOObjectFile>(&In))
 174     return macho::executeObjcopyOnBinary(Config, *MachOBinary, Out);
 175   else
 176     return createStringError(object_error::invalid_file_type,
 177                              "unsupported object file format");
 178 }
 179
 180 static Error executeObjcopyOnArchive(CopyConfig &Config, const Archive &Ar) {
 181   std::vector<NewArchiveMember> NewArchiveMembers;
 182   Error Err = Error::success();
 183   for (const Archive::Child &Child : Ar.children(Err)) {
 184     Expected<StringRef> ChildNameOrErr = Child.getName();
 185     if (!ChildNameOrErr)
 186       return createFileError(Ar.getFileName(), ChildNameOrErr.takeError());
 187
 188     Expected<std::unique_ptr<Binary>> ChildOrErr = Child.getAsBinary();
 189     if (!ChildOrErr)
 190       return createFileError(Ar.getFileName() + "(" + *ChildNameOrErr + ")",
 191                              ChildOrErr.takeError());
 192
 193     MemBuffer MB(ChildNameOrErr.get());
 194     if (Error E = executeObjcopyOnBinary(Config, *ChildOrErr->get(), MB))
 195       return E;
 196
 197     Expected<NewArchiveMember> Member =
 198         NewArchiveMember::getOldMember(Child, Config.DeterministicArchives);
 199     if (!Member)
 200       return createFileError(Ar.getFileName(), Member.takeError());
 201     Member->Buf = MB.releaseMemoryBuffer();
 202     Member->MemberName = Member->Buf->getBufferIdentifier();
 203     NewArchiveMembers.push_back(std::move(*Member));
 204   }
 205   if (Err)
 206     return createFileError(Config.InputFilename, std::move(Err));
 207
 208   return deepWriteArchive(Config.OutputFilename, NewArchiveMembers,
 209                           Ar.hasSymbolTable(), Ar.kind(),
 210                           Config.DeterministicArchives, Ar.isThin());
 211 }
 212
 213 static Error restoreStatOnFile(StringRef Filename,
 214                                const sys::fs::file_status &Stat,
 215                                bool PreserveDates) {
 216   int FD;
 217
 218   // Writing to stdout should not be treated as an error here, just
 219   // do not set access/modification times or permissions.
 220   if (Filename == "-")
 221     return Error::success();
 222
 223   if (auto EC =
 224           sys::fs::openFileForWrite(Filename, FD, sys::fs::CD_OpenExisting))
 225     return createFileError(Filename, EC);
 226
 227   if (PreserveDates)
 228     if (auto EC = sys::fs::setLastAccessAndModificationTime(
 229             FD, Stat.getLastAccessedTime(), Stat.getLastModificationTime()))
 230       return createFileError(Filename, EC);
 231
 232   sys::fs::file_status OStat;
 233   if (std::error_code EC = sys::fs::status(FD, OStat))
 234     return createFileError(Filename, EC);
 235   if (OStat.type() == sys::fs::file_type::regular_file)
 236 #ifdef _WIN32
 237     if (auto EC = sys::fs::setPermissions(
 238             Filename, static_cast<sys::fs::perms>(Stat.permissions() &
 239                                                   ~sys::fs::getUmask())))
 240 #else
 241     if (auto EC = sys::fs::setPermissions(
 242             FD, static_cast<sys::fs::perms>(Stat.permissions() &
 243                                             ~sys::fs::getUmask())))
 244 #endif
 245       return createFileError(Filename, EC);
 246
 247   if (auto EC = sys::Process::SafelyCloseFileDescriptor(FD))
 248     return createFileError(Filename, EC);
 249
 250   return Error::success();
 251 }
 252
 253 /// The function executeObjcopy does the higher level dispatch based on the type
 254 /// of input (raw binary, archive or single object file) and takes care of the
 255 /// format-agnostic modifications, i.e. preserving dates.
 256 static Error executeObjcopy(CopyConfig &Config) {
 257   sys::fs::file_status Stat;
 258   if (Config.InputFilename != "-") {
 259     if (auto EC = sys::fs::status(Config.InputFilename, Stat))
 260       return createFileError(Config.InputFilename, EC);
 261   } else {
 262     Stat.permissions(static_cast<sys::fs::perms>(0777));
 263   }
 264
 265   using ProcessRawFn = Error (*)(CopyConfig &, MemoryBuffer &, Buffer &);
 266   ProcessRawFn ProcessRaw;
 267   switch (Config.InputFormat) {
 268   case FileFormat::Binary:
 269     ProcessRaw = executeObjcopyOnRawBinary;
 270     break;
 271   case FileFormat::IHex:
 272     ProcessRaw = executeObjcopyOnIHex;
 273     break;
 274   default:
 275     ProcessRaw = nullptr;
 276   }
 277
 278   if (ProcessRaw) {
 279     auto BufOrErr = MemoryBuffer::getFileOrSTDIN(Config.InputFilename);
 280     if (!BufOrErr)
 281       return createFileError(Config.InputFilename, BufOrErr.getError());
 282     FileBuffer FB(Config.OutputFilename);
 283     if (Error E = ProcessRaw(Config, *BufOrErr->get(), FB))
 284       return E;
 285   } else {
 286     Expected<OwningBinary<llvm::object::Binary>> BinaryOrErr =
 287         createBinary(Config.InputFilename);
 288     if (!BinaryOrErr)
 289       return createFileError(Config.InputFilename, BinaryOrErr.takeError());
 290
 291     if (Archive *Ar = dyn_cast<Archive>(BinaryOrErr.get().getBinary())) {
 292       if (Error E = executeObjcopyOnArchive(Config, *Ar))
 293         return E;
 294     } else {
 295       FileBuffer FB(Config.OutputFilename);
 296       if (Error E = executeObjcopyOnBinary(Config,
 297                                            *BinaryOrErr.get().getBinary(), FB))
 298         return E;
 299     }
 300   }
 301
 302   if (Error E =
 303           restoreStatOnFile(Config.OutputFilename, Stat, Config.PreserveDates))
 304     return E;
 305
 306   if (!Config.SplitDWO.empty()) {
 307     Stat.permissions(static_cast<sys::fs::perms>(0666));
 308     if (Error E =
 309             restoreStatOnFile(Config.SplitDWO, Stat, Config.PreserveDates))
 310       return E;
 311   }
 312
 313   return Error::success();
 314 }
 315
 316 int main(int argc, char **argv) {
 317   InitLLVM X(argc, argv);
 318   ToolName = argv[0];
 319   bool IsStrip = sys::path::stem(ToolName).contains("strip");
 320
 321   // Expand response files.
 322   // TODO: Move these lines, which are copied from lib/Support/CommandLine.cpp,
 323   // into a separate function in the CommandLine library and call that function
 324   // here. This is duplicated code.
 325   SmallVector<const char *, 20> NewArgv(argv, argv + argc);
 326   BumpPtrAllocator A;
 327   StringSaver Saver(A);
 328   cl::ExpandResponseFiles(Saver,
 329                           Triple(sys::getProcessTriple()).isOSWindows()
 330                               ? cl::TokenizeWindowsCommandLine
 331                               : cl::TokenizeGNUCommandLine,
 332                           NewArgv);
 333
 334   auto Args = makeArrayRef(NewArgv).drop_front();
 335
 336   Expected<DriverConfig> DriverConfig =
 337       IsStrip ? parseStripOptions(Args, reportWarning)
 338               : parseObjcopyOptions(Args);
 339   if (!DriverConfig) {
 340     logAllUnhandledErrors(DriverConfig.takeError(),
 341                           WithColor::error(errs(), ToolName));
 342     return 1;
 343   }
 344   for (CopyConfig &CopyConfig : DriverConfig->CopyConfigs) {
 345     if (Error E = executeObjcopy(CopyConfig)) {
 346       logAllUnhandledErrors(std::move(E), WithColor::error(errs(), ToolName));
 347       return 1;
 348     }
 349   }
 350
 351   return 0;
 352 }