llvm-objcopy.cpp revision 363496 
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
51namespace llvm {
52namespace objcopy {
53
54// The name this program was invoked as.
55StringRef ToolName;
56
57LLVM_ATTRIBUTE_NORETURN void error(Twine Message) {
58  WithColor::error(errs(), ToolName) << Message << "\n";
59  exit(1);
60}
61
62LLVM_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
72LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, std::error_code EC) {
73  assert(EC);
74  error(createFileError(File, EC));
75}
76
77LLVM_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
87ErrorSuccess 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
96using namespace llvm;
97using namespace llvm::object;
98using 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.
102static 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.
135static 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.
145static 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).
165static 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
180static 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
213static 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.
256static 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
316namespace {
317
318enum class ToolType { Objcopy, Strip, InstallNameTool };
319
320} // anonymous namespace
321
322int main(int argc, char **argv) {
323  InitLLVM X(argc, argv);
324  ToolName = argv[0];
325
326  StringRef Stem = sys::path::stem(ToolName);
327  auto Is = [=](StringRef Tool) {
328    // We need to recognize the following filenames:
329    //
330    // llvm-objcopy -> objcopy
331    // strip-10.exe -> strip
332    // powerpc64-unknown-freebsd13-objcopy -> objcopy
333    // llvm-install-name-tool -> install-name-tool
334    auto I = Stem.rfind_lower(Tool);
335    return I != StringRef::npos &&
336           (I + Tool.size() == Stem.size() || !isAlnum(Stem[I + Tool.size()]));
337  };
338  ToolType Tool = ToolType::Objcopy;
339  if (Is("strip"))
340    Tool = ToolType::Strip;
341  else if (Is("install-name-tool") || Is("install_name_tool"))
342    Tool = ToolType::InstallNameTool;
343
344  // Expand response files.
345  // TODO: Move these lines, which are copied from lib/Support/CommandLine.cpp,
346  // into a separate function in the CommandLine library and call that function
347  // here. This is duplicated code.
348  SmallVector<const char *, 20> NewArgv(argv, argv + argc);
349  BumpPtrAllocator A;
350  StringSaver Saver(A);
351  cl::ExpandResponseFiles(Saver,
352                          Triple(sys::getProcessTriple()).isOSWindows()
353                              ? cl::TokenizeWindowsCommandLine
354                              : cl::TokenizeGNUCommandLine,
355                          NewArgv);
356
357  auto Args = makeArrayRef(NewArgv).drop_front();
358  Expected<DriverConfig> DriverConfig =
359      (Tool == ToolType::Strip) ? parseStripOptions(Args, reportWarning)
360                                : ((Tool == ToolType::InstallNameTool)
361                                       ? parseInstallNameToolOptions(Args)
362                                       : parseObjcopyOptions(Args, reportWarning));
363  if (!DriverConfig) {
364    logAllUnhandledErrors(DriverConfig.takeError(),
365                          WithColor::error(errs(), ToolName));
366    return 1;
367  }
368  for (CopyConfig &CopyConfig : DriverConfig->CopyConfigs) {
369    if (Error E = executeObjcopy(CopyConfig)) {
370      logAllUnhandledErrors(std::move(E), WithColor::error(errs(), ToolName));
371      return 1;
372    }
373  }
374
375  return 0;
376}
377