xref: /llvm-project/llvm/tools/llvm-objcopy/llvm-objcopy.cpp (revision 8ed7946a7d94f9d23b7f33356a1903d481daa5a0)
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 "Buffer.h"
10 #include "COFF/COFFObjcopy.h"
11 #include "CopyConfig.h"
12 #include "ELF/ELFObjcopy.h"
13 #include "MachO/MachOObjcopy.h"
14 #include "wasm/WasmObjcopy.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/Object/MachOUniversal.h"
29 #include "llvm/Object/Wasm.h"
30 #include "llvm/Option/Arg.h"
31 #include "llvm/Option/ArgList.h"
32 #include "llvm/Option/Option.h"
33 #include "llvm/Support/Casting.h"
34 #include "llvm/Support/CommandLine.h"
35 #include "llvm/Support/Error.h"
36 #include "llvm/Support/ErrorHandling.h"
37 #include "llvm/Support/ErrorOr.h"
38 #include "llvm/Support/Host.h"
39 #include "llvm/Support/InitLLVM.h"
40 #include "llvm/Support/Memory.h"
41 #include "llvm/Support/Path.h"
42 #include "llvm/Support/Process.h"
43 #include "llvm/Support/StringSaver.h"
44 #include "llvm/Support/WithColor.h"
45 #include "llvm/Support/raw_ostream.h"
46 #include <algorithm>
47 #include <cassert>
48 #include <cstdlib>
49 #include <memory>
50 #include <string>
51 #include <system_error>
52 #include <utility>
53 
54 namespace llvm {
55 namespace objcopy {
56 
57 // The name this program was invoked as.
58 StringRef ToolName;
59 
60 ErrorSuccess reportWarning(Error E) {
61   assert(E);
62   WithColor::warning(errs(), ToolName) << toString(std::move(E)) << '\n';
63   return Error::success();
64 }
65 
66 } // end namespace objcopy
67 } // end namespace llvm
68 
69 using namespace llvm;
70 using namespace llvm::object;
71 using namespace llvm::objcopy;
72 
73 // For regular archives this function simply calls llvm::writeArchive,
74 // For thin archives it writes the archive file itself as well as its members.
75 static Error deepWriteArchive(StringRef ArcName,
76                               ArrayRef<NewArchiveMember> NewMembers,
77                               bool WriteSymtab, object::Archive::Kind Kind,
78                               bool Deterministic, bool Thin) {
79   if (Error E = writeArchive(ArcName, NewMembers, WriteSymtab, Kind,
80                              Deterministic, Thin))
81     return createFileError(ArcName, std::move(E));
82 
83   if (!Thin)
84     return Error::success();
85 
86   for (const NewArchiveMember &Member : NewMembers) {
87     // Internally, FileBuffer will use the buffer created by
88     // FileOutputBuffer::create, for regular files (that is the case for
89     // deepWriteArchive) FileOutputBuffer::create will return OnDiskBuffer.
90     // OnDiskBuffer uses a temporary file and then renames it. So in reality
91     // there is no inefficiency / duplicated in-memory buffers in this case. For
92     // now in-memory buffers can not be completely avoided since
93     // NewArchiveMember still requires them even though writeArchive does not
94     // write them on disk.
95     FileBuffer FB(Member.MemberName);
96     if (Error E = FB.allocate(Member.Buf->getBufferSize()))
97       return E;
98     std::copy(Member.Buf->getBufferStart(), Member.Buf->getBufferEnd(),
99               FB.getBufferStart());
100     if (Error E = FB.commit())
101       return E;
102   }
103   return Error::success();
104 }
105 
106 /// The function executeObjcopyOnIHex does the dispatch based on the format
107 /// of the output specified by the command line options.
108 static Error executeObjcopyOnIHex(CopyConfig &Config, MemoryBuffer &In,
109                                   Buffer &Out) {
110   // TODO: support output formats other than ELF.
111   if (Error E = Config.parseELFConfig())
112     return E;
113   return elf::executeObjcopyOnIHex(Config, In, Out);
114 }
115 
116 /// The function executeObjcopyOnRawBinary does the dispatch based on the format
117 /// of the output specified by the command line options.
118 static Error executeObjcopyOnRawBinary(CopyConfig &Config, MemoryBuffer &In,
119                                        Buffer &Out) {
120   switch (Config.OutputFormat) {
121   case FileFormat::ELF:
122   // FIXME: Currently, we call elf::executeObjcopyOnRawBinary even if the
123   // output format is binary/ihex or it's not given. This behavior differs from
124   // GNU objcopy. See https://bugs.llvm.org/show_bug.cgi?id=42171 for details.
125   case FileFormat::Binary:
126   case FileFormat::IHex:
127   case FileFormat::Unspecified:
128     if (Error E = Config.parseELFConfig())
129       return E;
130     return elf::executeObjcopyOnRawBinary(Config, In, Out);
131   }
132 
133   llvm_unreachable("unsupported output format");
134 }
135 
136 /// The function executeObjcopyOnBinary does the dispatch based on the format
137 /// of the input binary (ELF, MachO or COFF).
138 static Error executeObjcopyOnBinary(CopyConfig &Config, object::Binary &In,
139                                     Buffer &Out) {
140   if (auto *ELFBinary = dyn_cast<object::ELFObjectFileBase>(&In)) {
141     if (Error E = Config.parseELFConfig())
142       return E;
143     return elf::executeObjcopyOnBinary(Config, *ELFBinary, Out);
144   } else if (auto *COFFBinary = dyn_cast<object::COFFObjectFile>(&In))
145     return coff::executeObjcopyOnBinary(Config, *COFFBinary, Out);
146   else if (auto *MachOBinary = dyn_cast<object::MachOObjectFile>(&In))
147     return macho::executeObjcopyOnBinary(Config, *MachOBinary, Out);
148   else if (auto *MachOUniversalBinary =
149                dyn_cast<object::MachOUniversalBinary>(&In))
150     return macho::executeObjcopyOnMachOUniversalBinary(
151         Config, *MachOUniversalBinary, Out);
152   else if (auto *WasmBinary = dyn_cast<object::WasmObjectFile>(&In))
153     return objcopy::wasm::executeObjcopyOnBinary(Config, *WasmBinary, Out);
154   else
155     return createStringError(object_error::invalid_file_type,
156                              "unsupported object file format");
157 }
158 
159 namespace llvm {
160 namespace objcopy {
161 
162 Expected<std::vector<NewArchiveMember>>
163 createNewArchiveMembers(CopyConfig &Config, const Archive &Ar) {
164   std::vector<NewArchiveMember> NewArchiveMembers;
165   Error Err = Error::success();
166   for (const Archive::Child &Child : Ar.children(Err)) {
167     Expected<StringRef> ChildNameOrErr = Child.getName();
168     if (!ChildNameOrErr)
169       return createFileError(Ar.getFileName(), ChildNameOrErr.takeError());
170 
171     Expected<std::unique_ptr<Binary>> ChildOrErr = Child.getAsBinary();
172     if (!ChildOrErr)
173       return createFileError(Ar.getFileName() + "(" + *ChildNameOrErr + ")",
174                              ChildOrErr.takeError());
175 
176     MemBuffer MB(ChildNameOrErr.get());
177     if (Error E = executeObjcopyOnBinary(Config, *ChildOrErr->get(), MB))
178       return std::move(E);
179 
180     Expected<NewArchiveMember> Member =
181         NewArchiveMember::getOldMember(Child, Config.DeterministicArchives);
182     if (!Member)
183       return createFileError(Ar.getFileName(), Member.takeError());
184     Member->Buf = MB.releaseMemoryBuffer();
185     Member->MemberName = Member->Buf->getBufferIdentifier();
186     NewArchiveMembers.push_back(std::move(*Member));
187   }
188   if (Err)
189     return createFileError(Config.InputFilename, std::move(Err));
190   return NewArchiveMembers;
191 }
192 
193 } // end namespace objcopy
194 } // end namespace llvm
195 
196 static Error executeObjcopyOnArchive(CopyConfig &Config,
197                                      const object::Archive &Ar) {
198   Expected<std::vector<NewArchiveMember>> NewArchiveMembersOrErr =
199       createNewArchiveMembers(Config, Ar);
200   if (!NewArchiveMembersOrErr)
201     return NewArchiveMembersOrErr.takeError();
202   return deepWriteArchive(Config.OutputFilename, *NewArchiveMembersOrErr,
203                           Ar.hasSymbolTable(), Ar.kind(),
204                           Config.DeterministicArchives, Ar.isThin());
205 }
206 
207 static Error restoreStatOnFile(StringRef Filename,
208                                const sys::fs::file_status &Stat,
209                                bool PreserveDates) {
210   int FD;
211 
212   // Writing to stdout should not be treated as an error here, just
213   // do not set access/modification times or permissions.
214   if (Filename == "-")
215     return Error::success();
216 
217   if (auto EC =
218           sys::fs::openFileForWrite(Filename, FD, sys::fs::CD_OpenExisting))
219     return createFileError(Filename, EC);
220 
221   if (PreserveDates)
222     if (auto EC = sys::fs::setLastAccessAndModificationTime(
223             FD, Stat.getLastAccessedTime(), Stat.getLastModificationTime()))
224       return createFileError(Filename, EC);
225 
226   sys::fs::file_status OStat;
227   if (std::error_code EC = sys::fs::status(FD, OStat))
228     return createFileError(Filename, EC);
229   if (OStat.type() == sys::fs::file_type::regular_file)
230 #ifdef _WIN32
231     if (auto EC = sys::fs::setPermissions(
232             Filename, static_cast<sys::fs::perms>(Stat.permissions() &
233                                                   ~sys::fs::getUmask())))
234 #else
235     if (auto EC = sys::fs::setPermissions(
236             FD, static_cast<sys::fs::perms>(Stat.permissions() &
237                                             ~sys::fs::getUmask())))
238 #endif
239       return createFileError(Filename, EC);
240 
241   if (auto EC = sys::Process::SafelyCloseFileDescriptor(FD))
242     return createFileError(Filename, EC);
243 
244   return Error::success();
245 }
246 
247 /// The function executeObjcopy does the higher level dispatch based on the type
248 /// of input (raw binary, archive or single object file) and takes care of the
249 /// format-agnostic modifications, i.e. preserving dates.
250 static Error executeObjcopy(CopyConfig &Config) {
251   sys::fs::file_status Stat;
252   if (Config.InputFilename != "-") {
253     if (auto EC = sys::fs::status(Config.InputFilename, Stat))
254       return createFileError(Config.InputFilename, EC);
255   } else {
256     Stat.permissions(static_cast<sys::fs::perms>(0777));
257   }
258 
259   using ProcessRawFn = Error (*)(CopyConfig &, MemoryBuffer &, Buffer &);
260   ProcessRawFn ProcessRaw;
261   switch (Config.InputFormat) {
262   case FileFormat::Binary:
263     ProcessRaw = executeObjcopyOnRawBinary;
264     break;
265   case FileFormat::IHex:
266     ProcessRaw = executeObjcopyOnIHex;
267     break;
268   default:
269     ProcessRaw = nullptr;
270   }
271 
272   if (ProcessRaw) {
273     auto BufOrErr = MemoryBuffer::getFileOrSTDIN(Config.InputFilename);
274     if (!BufOrErr)
275       return createFileError(Config.InputFilename, BufOrErr.getError());
276     FileBuffer FB(Config.OutputFilename);
277     if (Error E = ProcessRaw(Config, *BufOrErr->get(), FB))
278       return E;
279   } else {
280     Expected<OwningBinary<llvm::object::Binary>> BinaryOrErr =
281         createBinary(Config.InputFilename);
282     if (!BinaryOrErr)
283       return createFileError(Config.InputFilename, BinaryOrErr.takeError());
284 
285     if (Archive *Ar = dyn_cast<Archive>(BinaryOrErr.get().getBinary())) {
286       if (Error E = executeObjcopyOnArchive(Config, *Ar))
287         return E;
288     } else {
289       FileBuffer FB(Config.OutputFilename);
290       if (Error E = executeObjcopyOnBinary(Config,
291                                            *BinaryOrErr.get().getBinary(), FB))
292         return E;
293     }
294   }
295 
296   if (Error E =
297           restoreStatOnFile(Config.OutputFilename, Stat, Config.PreserveDates))
298     return E;
299 
300   if (!Config.SplitDWO.empty()) {
301     Stat.permissions(static_cast<sys::fs::perms>(0666));
302     if (Error E =
303             restoreStatOnFile(Config.SplitDWO, Stat, Config.PreserveDates))
304       return E;
305   }
306 
307   return Error::success();
308 }
309 
310 namespace {
311 
312 enum class ToolType { Objcopy, Strip, InstallNameTool, BitcodeStrip };
313 
314 } // anonymous namespace
315 
316 int main(int argc, char **argv) {
317   InitLLVM X(argc, argv);
318   ToolName = argv[0];
319 
320   StringRef Stem = sys::path::stem(ToolName);
321   auto Is = [=](StringRef Tool) {
322     // We need to recognize the following filenames:
323     //
324     // llvm-objcopy -> objcopy
325     // strip-10.exe -> strip
326     // powerpc64-unknown-freebsd13-objcopy -> objcopy
327     // llvm-install-name-tool -> install-name-tool
328     auto I = Stem.rfind_lower(Tool);
329     return I != StringRef::npos &&
330            (I + Tool.size() == Stem.size() || !isAlnum(Stem[I + Tool.size()]));
331   };
332   ToolType Tool = ToolType::Objcopy;
333   if (Is("bitcode-strip") || Is("bitcode_strip"))
334     Tool = ToolType::BitcodeStrip;
335   else if (Is("strip"))
336     Tool = ToolType::Strip;
337   else if (Is("install-name-tool") || Is("install_name_tool"))
338     Tool = ToolType::InstallNameTool;
339 
340   // Expand response files.
341   // TODO: Move these lines, which are copied from lib/Support/CommandLine.cpp,
342   // into a separate function in the CommandLine library and call that function
343   // here. This is duplicated code.
344   SmallVector<const char *, 20> NewArgv(argv, argv + argc);
345   BumpPtrAllocator A;
346   StringSaver Saver(A);
347   cl::ExpandResponseFiles(Saver,
348                           Triple(sys::getProcessTriple()).isOSWindows()
349                               ? cl::TokenizeWindowsCommandLine
350                               : cl::TokenizeGNUCommandLine,
351                           NewArgv);
352 
353   auto Args = makeArrayRef(NewArgv).drop_front();
354   Expected<DriverConfig> DriverConfig =
355       (Tool == ToolType::Strip)
356           ? parseStripOptions(Args, reportWarning)
357           : ((Tool == ToolType::InstallNameTool)
358                  ? parseInstallNameToolOptions(Args)
359                  : ((Tool == ToolType::BitcodeStrip)
360                         ? parseBitcodeStripOptions(Args)
361                         : parseObjcopyOptions(Args, reportWarning)));
362   if (!DriverConfig) {
363     logAllUnhandledErrors(DriverConfig.takeError(),
364                           WithColor::error(errs(), ToolName));
365     return 1;
366   }
367   for (CopyConfig &CopyConfig : DriverConfig->CopyConfigs) {
368     if (Error E = executeObjcopy(CopyConfig)) {
369       logAllUnhandledErrors(std::move(E), WithColor::error(errs(), ToolName));
370       return 1;
371     }
372   }
373 
374   return 0;
375 }
376