xref: /netbsd-src/external/apache2/llvm/dist/llvm/tools/llvm-objcopy/llvm-objcopy.cpp (revision 82d56013d7b633d116a93943de88e08335357a7c)
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 namespace llvm {
63 namespace objcopy {
64 
65 // The name this program was invoked as.
66 StringRef ToolName;
67 
reportWarning(Error E)68 ErrorSuccess reportWarning(Error E) {
69   assert(E);
70   WithColor::warning(errs(), ToolName) << toString(std::move(E)) << '\n';
71   return Error::success();
72 }
73 
getDriverConfig(ArrayRef<const char * > Args)74 static Expected<DriverConfig> getDriverConfig(ArrayRef<const char *> Args) {
75   StringRef Stem = sys::path::stem(ToolName);
76   auto Is = [=](StringRef Tool) {
77     // We need to recognize the following filenames:
78     //
79     // llvm-objcopy -> objcopy
80     // strip-10.exe -> strip
81     // powerpc64-unknown-freebsd13-objcopy -> objcopy
82     // llvm-install-name-tool -> install-name-tool
83     auto I = Stem.rfind_lower(Tool);
84     return I != StringRef::npos &&
85            (I + Tool.size() == Stem.size() || !isAlnum(Stem[I + Tool.size()]));
86   };
87 
88   if (Is("bitcode-strip") || Is("bitcode_strip"))
89     return parseBitcodeStripOptions(Args);
90   else if (Is("strip"))
91     return parseStripOptions(Args, reportWarning);
92   else if (Is("install-name-tool") || Is("install_name_tool"))
93     return parseInstallNameToolOptions(Args);
94   else
95     return parseObjcopyOptions(Args, reportWarning);
96 }
97 
98 } // end namespace objcopy
99 } // end namespace llvm
100 
101 using namespace llvm;
102 using namespace llvm::object;
103 using namespace llvm::objcopy;
104 
105 // For regular archives this function simply calls llvm::writeArchive,
106 // For thin archives it writes the archive file itself as well as its members.
deepWriteArchive(StringRef ArcName,ArrayRef<NewArchiveMember> NewMembers,bool WriteSymtab,object::Archive::Kind Kind,bool Deterministic,bool Thin)107 static Error deepWriteArchive(StringRef ArcName,
108                               ArrayRef<NewArchiveMember> NewMembers,
109                               bool WriteSymtab, object::Archive::Kind Kind,
110                               bool Deterministic, bool Thin) {
111   if (Error E = writeArchive(ArcName, NewMembers, WriteSymtab, Kind,
112                              Deterministic, Thin))
113     return createFileError(ArcName, std::move(E));
114 
115   if (!Thin)
116     return Error::success();
117 
118   for (const NewArchiveMember &Member : NewMembers) {
119     // For regular files (as is the case for deepWriteArchive),
120     // FileOutputBuffer::create will return OnDiskBuffer.
121     // OnDiskBuffer uses a temporary file and then renames it. So in reality
122     // there is no inefficiency / duplicated in-memory buffers in this case. For
123     // now in-memory buffers can not be completely avoided since
124     // NewArchiveMember still requires them even though writeArchive does not
125     // write them on disk.
126     Expected<std::unique_ptr<FileOutputBuffer>> FB =
127         FileOutputBuffer::create(Member.MemberName, Member.Buf->getBufferSize(),
128                                  FileOutputBuffer::F_executable);
129     if (!FB)
130       return FB.takeError();
131     std::copy(Member.Buf->getBufferStart(), Member.Buf->getBufferEnd(),
132               (*FB)->getBufferStart());
133     if (Error E = (*FB)->commit())
134       return E;
135   }
136   return Error::success();
137 }
138 
139 /// The function executeObjcopyOnIHex does the dispatch based on the format
140 /// of the output specified by the command line options.
executeObjcopyOnIHex(ConfigManager & ConfigMgr,MemoryBuffer & In,raw_ostream & Out)141 static Error executeObjcopyOnIHex(ConfigManager &ConfigMgr, MemoryBuffer &In,
142                                   raw_ostream &Out) {
143   // TODO: support output formats other than ELF.
144   Expected<const ELFConfig &> ELFConfig = ConfigMgr.getELFConfig();
145   if (!ELFConfig)
146     return ELFConfig.takeError();
147 
148   return elf::executeObjcopyOnIHex(ConfigMgr.getCommonConfig(), *ELFConfig, In,
149                                    Out);
150 }
151 
152 /// The function executeObjcopyOnRawBinary does the dispatch based on the format
153 /// of the output specified by the command line options.
executeObjcopyOnRawBinary(ConfigManager & ConfigMgr,MemoryBuffer & In,raw_ostream & Out)154 static Error executeObjcopyOnRawBinary(ConfigManager &ConfigMgr,
155                                        MemoryBuffer &In, raw_ostream &Out) {
156   const CommonConfig &Config = ConfigMgr.getCommonConfig();
157   switch (Config.OutputFormat) {
158   case FileFormat::ELF:
159   // FIXME: Currently, we call elf::executeObjcopyOnRawBinary even if the
160   // output format is binary/ihex or it's not given. This behavior differs from
161   // GNU objcopy. See https://bugs.llvm.org/show_bug.cgi?id=42171 for details.
162   case FileFormat::Binary:
163   case FileFormat::IHex:
164   case FileFormat::Unspecified:
165     Expected<const ELFConfig &> ELFConfig = ConfigMgr.getELFConfig();
166     if (!ELFConfig)
167       return ELFConfig.takeError();
168 
169     return elf::executeObjcopyOnRawBinary(Config, *ELFConfig, In, Out);
170   }
171 
172   llvm_unreachable("unsupported output format");
173 }
174 
175 /// The function executeObjcopyOnBinary does the dispatch based on the format
176 /// of the input binary (ELF, MachO or COFF).
executeObjcopyOnBinary(const MultiFormatConfig & Config,object::Binary & In,raw_ostream & Out)177 static Error executeObjcopyOnBinary(const MultiFormatConfig &Config,
178                                     object::Binary &In, raw_ostream &Out) {
179   if (auto *ELFBinary = dyn_cast<object::ELFObjectFileBase>(&In)) {
180     Expected<const ELFConfig &> ELFConfig = Config.getELFConfig();
181     if (!ELFConfig)
182       return ELFConfig.takeError();
183 
184     return elf::executeObjcopyOnBinary(Config.getCommonConfig(), *ELFConfig,
185                                        *ELFBinary, Out);
186   } else if (auto *COFFBinary = dyn_cast<object::COFFObjectFile>(&In)) {
187     Expected<const COFFConfig &> COFFConfig = Config.getCOFFConfig();
188     if (!COFFConfig)
189       return COFFConfig.takeError();
190 
191     return coff::executeObjcopyOnBinary(Config.getCommonConfig(), *COFFConfig,
192                                         *COFFBinary, Out);
193   } else if (auto *MachOBinary = dyn_cast<object::MachOObjectFile>(&In)) {
194     Expected<const MachOConfig &> MachOConfig = Config.getMachOConfig();
195     if (!MachOConfig)
196       return MachOConfig.takeError();
197 
198     return macho::executeObjcopyOnBinary(Config.getCommonConfig(), *MachOConfig,
199                                          *MachOBinary, Out);
200   } else if (auto *MachOUniversalBinary =
201                  dyn_cast<object::MachOUniversalBinary>(&In)) {
202     return macho::executeObjcopyOnMachOUniversalBinary(
203         Config, *MachOUniversalBinary, Out);
204   } else if (auto *WasmBinary = dyn_cast<object::WasmObjectFile>(&In)) {
205     Expected<const WasmConfig &> WasmConfig = Config.getWasmConfig();
206     if (!WasmConfig)
207       return WasmConfig.takeError();
208 
209     return objcopy::wasm::executeObjcopyOnBinary(Config.getCommonConfig(),
210                                                  *WasmConfig, *WasmBinary, Out);
211   } else
212     return createStringError(object_error::invalid_file_type,
213                              "unsupported object file format");
214 }
215 
216 namespace llvm {
217 namespace objcopy {
218 
219 Expected<std::vector<NewArchiveMember>>
createNewArchiveMembers(const MultiFormatConfig & Config,const Archive & Ar)220 createNewArchiveMembers(const MultiFormatConfig &Config, const Archive &Ar) {
221   std::vector<NewArchiveMember> NewArchiveMembers;
222   Error Err = Error::success();
223   for (const Archive::Child &Child : Ar.children(Err)) {
224     Expected<StringRef> ChildNameOrErr = Child.getName();
225     if (!ChildNameOrErr)
226       return createFileError(Ar.getFileName(), ChildNameOrErr.takeError());
227 
228     Expected<std::unique_ptr<Binary>> ChildOrErr = Child.getAsBinary();
229     if (!ChildOrErr)
230       return createFileError(Ar.getFileName() + "(" + *ChildNameOrErr + ")",
231                              ChildOrErr.takeError());
232 
233     SmallVector<char, 0> Buffer;
234     raw_svector_ostream MemStream(Buffer);
235 
236     if (Error E = executeObjcopyOnBinary(Config, *ChildOrErr->get(), MemStream))
237       return std::move(E);
238 
239     Expected<NewArchiveMember> Member = NewArchiveMember::getOldMember(
240         Child, Config.getCommonConfig().DeterministicArchives);
241     if (!Member)
242       return createFileError(Ar.getFileName(), Member.takeError());
243 
244     Member->Buf = std::make_unique<SmallVectorMemoryBuffer>(
245         std::move(Buffer), ChildNameOrErr.get());
246     Member->MemberName = Member->Buf->getBufferIdentifier();
247     NewArchiveMembers.push_back(std::move(*Member));
248   }
249   if (Err)
250     return createFileError(Config.getCommonConfig().InputFilename,
251                            std::move(Err));
252   return std::move(NewArchiveMembers);
253 }
254 
255 } // end namespace objcopy
256 } // end namespace llvm
257 
executeObjcopyOnArchive(const ConfigManager & ConfigMgr,const object::Archive & Ar)258 static Error executeObjcopyOnArchive(const ConfigManager &ConfigMgr,
259                                      const object::Archive &Ar) {
260   Expected<std::vector<NewArchiveMember>> NewArchiveMembersOrErr =
261       createNewArchiveMembers(ConfigMgr, Ar);
262   if (!NewArchiveMembersOrErr)
263     return NewArchiveMembersOrErr.takeError();
264   const CommonConfig &Config = ConfigMgr.getCommonConfig();
265   return deepWriteArchive(Config.OutputFilename, *NewArchiveMembersOrErr,
266                           Ar.hasSymbolTable(), Ar.kind(),
267                           Config.DeterministicArchives, Ar.isThin());
268 }
269 
restoreStatOnFile(StringRef Filename,const sys::fs::file_status & Stat,const ConfigManager & ConfigMgr)270 static Error restoreStatOnFile(StringRef Filename,
271                                const sys::fs::file_status &Stat,
272                                const ConfigManager &ConfigMgr) {
273   int FD;
274   const CommonConfig &Config = ConfigMgr.getCommonConfig();
275 
276   // Writing to stdout should not be treated as an error here, just
277   // do not set access/modification times or permissions.
278   if (Filename == "-")
279     return Error::success();
280 
281   if (auto EC =
282           sys::fs::openFileForWrite(Filename, FD, sys::fs::CD_OpenExisting))
283     return createFileError(Filename, EC);
284 
285   if (Config.PreserveDates)
286     if (auto EC = sys::fs::setLastAccessAndModificationTime(
287             FD, Stat.getLastAccessedTime(), Stat.getLastModificationTime()))
288       return createFileError(Filename, EC);
289 
290   sys::fs::file_status OStat;
291   if (std::error_code EC = sys::fs::status(FD, OStat))
292     return createFileError(Filename, EC);
293   if (OStat.type() == sys::fs::file_type::regular_file) {
294 #ifndef _WIN32
295     // Keep ownership if llvm-objcopy is called under root.
296     if (Config.InputFilename == Config.OutputFilename && OStat.getUser() == 0)
297       sys::fs::changeFileOwnership(FD, Stat.getUser(), Stat.getGroup());
298 #endif
299 
300     sys::fs::perms Perm = Stat.permissions();
301     if (Config.InputFilename != Config.OutputFilename)
302       Perm = static_cast<sys::fs::perms>(Perm & ~sys::fs::getUmask() & ~06000);
303 #ifdef _WIN32
304     if (auto EC = sys::fs::setPermissions(Filename, Perm))
305 #else
306     if (auto EC = sys::fs::setPermissions(FD, Perm))
307 #endif
308       return createFileError(Filename, EC);
309   }
310 
311   if (auto EC = sys::Process::SafelyCloseFileDescriptor(FD))
312     return createFileError(Filename, EC);
313 
314   return Error::success();
315 }
316 
317 /// The function executeObjcopy does the higher level dispatch based on the type
318 /// of input (raw binary, archive or single object file) and takes care of the
319 /// format-agnostic modifications, i.e. preserving dates.
executeObjcopy(ConfigManager & ConfigMgr)320 static Error executeObjcopy(ConfigManager &ConfigMgr) {
321   CommonConfig &Config = ConfigMgr.Common;
322 
323   sys::fs::file_status Stat;
324   if (Config.InputFilename != "-") {
325     if (auto EC = sys::fs::status(Config.InputFilename, Stat))
326       return createFileError(Config.InputFilename, EC);
327   } else {
328     Stat.permissions(static_cast<sys::fs::perms>(0777));
329   }
330 
331   std::function<Error(raw_ostream & OutFile)> ObjcopyFunc;
332 
333   OwningBinary<llvm::object::Binary> BinaryHolder;
334   std::unique_ptr<MemoryBuffer> MemoryBufferHolder;
335 
336   if (Config.InputFormat == FileFormat::Binary ||
337       Config.InputFormat == FileFormat::IHex) {
338     ErrorOr<std::unique_ptr<MemoryBuffer>> BufOrErr =
339         MemoryBuffer::getFileOrSTDIN(Config.InputFilename);
340     if (!BufOrErr)
341       return createFileError(Config.InputFilename, BufOrErr.getError());
342     MemoryBufferHolder = std::move(*BufOrErr);
343 
344     if (Config.InputFormat == FileFormat::Binary)
345       ObjcopyFunc = [&](raw_ostream &OutFile) -> Error {
346         // Handle FileFormat::Binary.
347         return executeObjcopyOnRawBinary(ConfigMgr, *MemoryBufferHolder,
348                                          OutFile);
349       };
350     else
351       ObjcopyFunc = [&](raw_ostream &OutFile) -> Error {
352         // Handle FileFormat::IHex.
353         return executeObjcopyOnIHex(ConfigMgr, *MemoryBufferHolder, OutFile);
354       };
355   } else {
356     Expected<OwningBinary<llvm::object::Binary>> BinaryOrErr =
357         createBinary(Config.InputFilename);
358     if (!BinaryOrErr)
359       return createFileError(Config.InputFilename, BinaryOrErr.takeError());
360     BinaryHolder = std::move(*BinaryOrErr);
361 
362     if (Archive *Ar = dyn_cast<Archive>(BinaryHolder.getBinary())) {
363       // Handle Archive.
364       if (Error E = executeObjcopyOnArchive(ConfigMgr, *Ar))
365         return E;
366     } else {
367       // Handle llvm::object::Binary.
368       ObjcopyFunc = [&](raw_ostream &OutFile) -> Error {
369         return executeObjcopyOnBinary(ConfigMgr, *BinaryHolder.getBinary(),
370                                       OutFile);
371       };
372     }
373   }
374 
375   if (ObjcopyFunc) {
376     if (Config.SplitDWO.empty()) {
377       // Apply transformations described by Config and store result into
378       // Config.OutputFilename using specified ObjcopyFunc function.
379       if (Error E = writeToOutput(Config.OutputFilename, ObjcopyFunc))
380         return E;
381     } else {
382       Config.ExtractDWO = true;
383       Config.StripDWO = false;
384       // Copy .dwo tables from the Config.InputFilename into Config.SplitDWO
385       // file using specified ObjcopyFunc function.
386       if (Error E = writeToOutput(Config.SplitDWO, ObjcopyFunc))
387         return E;
388       Config.ExtractDWO = false;
389       Config.StripDWO = true;
390       // Apply transformations described by Config, remove .dwo tables and
391       // store result into Config.OutputFilename using specified ObjcopyFunc
392       // function.
393       if (Error E = writeToOutput(Config.OutputFilename, ObjcopyFunc))
394         return E;
395     }
396   }
397 
398   if (Error E = restoreStatOnFile(Config.OutputFilename, Stat, ConfigMgr))
399     return E;
400 
401   if (!Config.SplitDWO.empty()) {
402     Stat.permissions(static_cast<sys::fs::perms>(0666));
403     if (Error E = restoreStatOnFile(Config.SplitDWO, Stat, ConfigMgr))
404       return E;
405   }
406 
407   return Error::success();
408 }
409 
410 namespace {
411 
412 } // anonymous namespace
413 
main(int argc,char ** argv)414 int main(int argc, char **argv) {
415   InitLLVM X(argc, argv);
416   ToolName = argv[0];
417 
418   // Expand response files.
419   // TODO: Move these lines, which are copied from lib/Support/CommandLine.cpp,
420   // into a separate function in the CommandLine library and call that function
421   // here. This is duplicated code.
422   SmallVector<const char *, 20> NewArgv(argv, argv + argc);
423   BumpPtrAllocator A;
424   StringSaver Saver(A);
425   cl::ExpandResponseFiles(Saver,
426                           Triple(sys::getProcessTriple()).isOSWindows()
427                               ? cl::TokenizeWindowsCommandLine
428                               : cl::TokenizeGNUCommandLine,
429                           NewArgv);
430 
431   auto Args = makeArrayRef(NewArgv).drop_front();
432   Expected<DriverConfig> DriverConfig = getDriverConfig(Args);
433 
434   if (!DriverConfig) {
435     logAllUnhandledErrors(DriverConfig.takeError(),
436                           WithColor::error(errs(), ToolName));
437     return 1;
438   }
439   for (ConfigManager &ConfigMgr : DriverConfig->CopyConfigs) {
440     if (Error E = executeObjcopy(ConfigMgr)) {
441       logAllUnhandledErrors(std::move(E), WithColor::error(errs(), ToolName));
442       return 1;
443     }
444   }
445 
446   return 0;
447 }
448