xref: /llvm-project/llvm/tools/llvm-objcopy/llvm-objcopy.cpp (revision db2036e1f5b74876c5574ec526a44d042101fb3b) 
1 //===- llvm-objcopy.cpp ---------------------------------------------------===//
2 //
3 //                      The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "llvm-objcopy.h"
11 #include "Object.h"
12 #include "llvm/ADT/STLExtras.h"
13 #include "llvm/ADT/StringRef.h"
14 #include "llvm/ADT/Twine.h"
15 #include "llvm/BinaryFormat/ELF.h"
16 #include "llvm/Object/Archive.h"
17 #include "llvm/Object/ArchiveWriter.h"
18 #include "llvm/Object/Binary.h"
19 #include "llvm/Object/ELFObjectFile.h"
20 #include "llvm/Object/ELFTypes.h"
21 #include "llvm/Object/Error.h"
22 #include "llvm/Option/Arg.h"
23 #include "llvm/Option/ArgList.h"
24 #include "llvm/Option/Option.h"
25 #include "llvm/Support/Casting.h"
26 #include "llvm/Support/CommandLine.h"
27 #include "llvm/Support/Compiler.h"
28 #include "llvm/Support/Error.h"
29 #include "llvm/Support/ErrorHandling.h"
30 #include "llvm/Support/ErrorOr.h"
31 #include "llvm/Support/FileOutputBuffer.h"
32 #include "llvm/Support/InitLLVM.h"
33 #include "llvm/Support/Path.h"
34 #include "llvm/Support/raw_ostream.h"
35 #include <algorithm>
36 #include <cassert>
37 #include <cstdlib>
38 #include <functional>
39 #include <iterator>
40 #include <memory>
41 #include <string>
42 #include <system_error>
43 #include <utility>
44 
45 using namespace llvm;
46 using namespace llvm::objcopy;
47 using namespace object;
48 using namespace ELF;
49 
50 namespace {
51 
52 enum ObjcopyID {
53   OBJCOPY_INVALID = 0, // This is not an option ID.
54 #define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
55                HELPTEXT, METAVAR, VALUES)                                      \
56   OBJCOPY_##ID,
57 #include "ObjcopyOpts.inc"
58 #undef OPTION
59 };
60 
61 #define PREFIX(NAME, VALUE) const char *const OBJCOPY_##NAME[] = VALUE;
62 #include "ObjcopyOpts.inc"
63 #undef PREFIX
64 
65 static const opt::OptTable::Info ObjcopyInfoTable[] = {
66 #define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
67                HELPTEXT, METAVAR, VALUES)                                      \
68   {OBJCOPY_##PREFIX,                                                           \
69    NAME,                                                                       \
70    HELPTEXT,                                                                   \
71    METAVAR,                                                                    \
72    OBJCOPY_##ID,                                                               \
73    opt::Option::KIND##Class,                                                   \
74    PARAM,                                                                      \
75    FLAGS,                                                                      \
76    OBJCOPY_##GROUP,                                                            \
77    OBJCOPY_##ALIAS,                                                            \
78    ALIASARGS,                                                                  \
79    VALUES},
80 #include "ObjcopyOpts.inc"
81 #undef OPTION
82 };
83 
84 class ObjcopyOptTable : public opt::OptTable {
85 public:
86   ObjcopyOptTable() : OptTable(ObjcopyInfoTable, true) {}
87 };
88 
89 enum StripID {
90   STRIP_INVALID = 0, // This is not an option ID.
91 #define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
92                HELPTEXT, METAVAR, VALUES)                                      \
93   STRIP_##ID,
94 #include "StripOpts.inc"
95 #undef OPTION
96 };
97 
98 #define PREFIX(NAME, VALUE) const char *const STRIP_##NAME[] = VALUE;
99 #include "StripOpts.inc"
100 #undef PREFIX
101 
102 static const opt::OptTable::Info StripInfoTable[] = {
103 #define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
104                HELPTEXT, METAVAR, VALUES)                                      \
105   {STRIP_##PREFIX, NAME,       HELPTEXT,                                       \
106    METAVAR,        STRIP_##ID, opt::Option::KIND##Class,                       \
107    PARAM,          FLAGS,      STRIP_##GROUP,                                  \
108    STRIP_##ALIAS,  ALIASARGS,  VALUES},
109 #include "StripOpts.inc"
110 #undef OPTION
111 };
112 
113 class StripOptTable : public opt::OptTable {
114 public:
115   StripOptTable() : OptTable(StripInfoTable, true) {}
116 };
117 
118 struct CopyConfig {
119   StringRef OutputFilename;
120   StringRef InputFilename;
121   StringRef OutputFormat;
122   StringRef InputFormat;
123   StringRef BinaryArch;
124 
125   StringRef SplitDWO;
126   StringRef AddGnuDebugLink;
127   std::vector<StringRef> ToRemove;
128   std::vector<StringRef> Keep;
129   std::vector<StringRef> OnlyKeep;
130   std::vector<StringRef> AddSection;
131   std::vector<StringRef> SymbolsToLocalize;
132   std::vector<StringRef> SymbolsToGlobalize;
133   std::vector<StringRef> SymbolsToWeaken;
134   std::vector<StringRef> SymbolsToRemove;
135   std::vector<StringRef> SymbolsToKeep;
136   StringMap<StringRef> SectionsToRename;
137   StringMap<StringRef> SymbolsToRename;
138   bool StripAll = false;
139   bool StripAllGNU = false;
140   bool StripDebug = false;
141   bool StripSections = false;
142   bool StripNonAlloc = false;
143   bool StripDWO = false;
144   bool StripUnneeded = false;
145   bool ExtractDWO = false;
146   bool LocalizeHidden = false;
147   bool Weaken = false;
148   bool DiscardAll = false;
149   bool OnlyKeepDebug = false;
150   bool KeepFileSymbols = false;
151 };
152 
153 using SectionPred = std::function<bool(const SectionBase &Sec)>;
154 
155 } // namespace
156 
157 namespace llvm {
158 namespace objcopy {
159 
160 // The name this program was invoked as.
161 StringRef ToolName;
162 
163 LLVM_ATTRIBUTE_NORETURN void error(Twine Message) {
164   errs() << ToolName << ": " << Message << ".\n";
165   errs().flush();
166   exit(1);
167 }
168 
169 LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, std::error_code EC) {
170   assert(EC);
171   errs() << ToolName << ": '" << File << "': " << EC.message() << ".\n";
172   exit(1);
173 }
174 
175 LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, Error E) {
176   assert(E);
177   std::string Buf;
178   raw_string_ostream OS(Buf);
179   logAllUnhandledErrors(std::move(E), OS, "");
180   OS.flush();
181   errs() << ToolName << ": '" << File << "': " << Buf;
182   exit(1);
183 }
184 
185 } // end namespace objcopy
186 } // end namespace llvm
187 
188 static bool IsDWOSection(const SectionBase &Sec) {
189   return Sec.Name.endswith(".dwo");
190 }
191 
192 static bool OnlyKeepDWOPred(const Object &Obj, const SectionBase &Sec) {
193   // We can't remove the section header string table.
194   if (&Sec == Obj.SectionNames)
195     return false;
196   // Short of keeping the string table we want to keep everything that is a DWO
197   // section and remove everything else.
198   return !IsDWOSection(Sec);
199 }
200 
201 static std::unique_ptr<Writer> CreateWriter(const CopyConfig &Config,
202                                             Object &Obj, Buffer &Buf,
203                                             ElfType OutputElfType) {
204   if (Config.OutputFormat == "binary") {
205     return llvm::make_unique<BinaryWriter>(Obj, Buf);
206   }
207   // Depending on the initial ELFT and OutputFormat we need a different Writer.
208   switch (OutputElfType) {
209   case ELFT_ELF32LE:
210     return llvm::make_unique<ELFWriter<ELF32LE>>(Obj, Buf,
211                                                  !Config.StripSections);
212   case ELFT_ELF64LE:
213     return llvm::make_unique<ELFWriter<ELF64LE>>(Obj, Buf,
214                                                  !Config.StripSections);
215   case ELFT_ELF32BE:
216     return llvm::make_unique<ELFWriter<ELF32BE>>(Obj, Buf,
217                                                  !Config.StripSections);
218   case ELFT_ELF64BE:
219     return llvm::make_unique<ELFWriter<ELF64BE>>(Obj, Buf,
220                                                  !Config.StripSections);
221   }
222   llvm_unreachable("Invalid output format");
223 }
224 
225 static void SplitDWOToFile(const CopyConfig &Config, const Reader &Reader,
226                            StringRef File, ElfType OutputElfType) {
227   auto DWOFile = Reader.create();
228   DWOFile->removeSections(
229       [&](const SectionBase &Sec) { return OnlyKeepDWOPred(*DWOFile, Sec); });
230   FileBuffer FB(File);
231   auto Writer = CreateWriter(Config, *DWOFile, FB, OutputElfType);
232   Writer->finalize();
233   Writer->write();
234 }
235 
236 // This function handles the high level operations of GNU objcopy including
237 // handling command line options. It's important to outline certain properties
238 // we expect to hold of the command line operations. Any operation that "keeps"
239 // should keep regardless of a remove. Additionally any removal should respect
240 // any previous removals. Lastly whether or not something is removed shouldn't
241 // depend a) on the order the options occur in or b) on some opaque priority
242 // system. The only priority is that keeps/copies overrule removes.
243 static void HandleArgs(const CopyConfig &Config, Object &Obj,
244                        const Reader &Reader, ElfType OutputElfType) {
245 
246   if (!Config.SplitDWO.empty()) {
247     SplitDWOToFile(Config, Reader, Config.SplitDWO, OutputElfType);
248   }
249 
250   // TODO: update or remove symbols only if there is an option that affects
251   // them.
252   if (Obj.SymbolTable) {
253     Obj.SymbolTable->updateSymbols([&](Symbol &Sym) {
254       if ((Config.LocalizeHidden &&
255            (Sym.Visibility == STV_HIDDEN || Sym.Visibility == STV_INTERNAL)) ||
256           (!Config.SymbolsToLocalize.empty() &&
257            is_contained(Config.SymbolsToLocalize, Sym.Name)))
258         Sym.Binding = STB_LOCAL;
259 
260       if (!Config.SymbolsToGlobalize.empty() &&
261           is_contained(Config.SymbolsToGlobalize, Sym.Name))
262         Sym.Binding = STB_GLOBAL;
263 
264       if (!Config.SymbolsToWeaken.empty() &&
265           is_contained(Config.SymbolsToWeaken, Sym.Name) &&
266           Sym.Binding == STB_GLOBAL)
267         Sym.Binding = STB_WEAK;
268 
269       if (Config.Weaken && Sym.Binding == STB_GLOBAL &&
270           Sym.getShndx() != SHN_UNDEF)
271         Sym.Binding = STB_WEAK;
272 
273       const auto I = Config.SymbolsToRename.find(Sym.Name);
274       if (I != Config.SymbolsToRename.end())
275         Sym.Name = I->getValue();
276     });
277 
278     // The purpose of this loop is to mark symbols referenced by sections
279     // (like GroupSection or RelocationSection). This way, we know which
280     // symbols are still 'needed' and wich are not.
281     if (Config.StripUnneeded) {
282       for (auto &Section : Obj.sections())
283         Section.markSymbols();
284     }
285 
286     Obj.removeSymbols([&](const Symbol &Sym) {
287       if ((!Config.SymbolsToKeep.empty() &&
288            is_contained(Config.SymbolsToKeep, Sym.Name)) ||
289           (Config.KeepFileSymbols && Sym.Type == STT_FILE))
290         return false;
291 
292       if (Config.DiscardAll && Sym.Binding == STB_LOCAL &&
293           Sym.getShndx() != SHN_UNDEF && Sym.Type != STT_FILE &&
294           Sym.Type != STT_SECTION)
295         return true;
296 
297       if (Config.StripAll || Config.StripAllGNU)
298         return true;
299 
300       if (!Config.SymbolsToRemove.empty() &&
301           is_contained(Config.SymbolsToRemove, Sym.Name)) {
302         return true;
303       }
304 
305       if (Config.StripUnneeded && !Sym.Referenced &&
306           (Sym.Binding == STB_LOCAL || Sym.getShndx() == SHN_UNDEF) &&
307           Sym.Type != STT_FILE && Sym.Type != STT_SECTION)
308         return true;
309 
310       return false;
311     });
312   }
313 
314   SectionPred RemovePred = [](const SectionBase &) { return false; };
315 
316   // Removes:
317   if (!Config.ToRemove.empty()) {
318     RemovePred = [&Config](const SectionBase &Sec) {
319       return std::find(std::begin(Config.ToRemove), std::end(Config.ToRemove),
320                        Sec.Name) != std::end(Config.ToRemove);
321     };
322   }
323 
324   if (Config.StripDWO || !Config.SplitDWO.empty())
325     RemovePred = [RemovePred](const SectionBase &Sec) {
326       return IsDWOSection(Sec) || RemovePred(Sec);
327     };
328 
329   if (Config.ExtractDWO)
330     RemovePred = [RemovePred, &Obj](const SectionBase &Sec) {
331       return OnlyKeepDWOPred(Obj, Sec) || RemovePred(Sec);
332     };
333 
334   if (Config.StripAllGNU)
335     RemovePred = [RemovePred, &Obj](const SectionBase &Sec) {
336       if (RemovePred(Sec))
337         return true;
338       if ((Sec.Flags & SHF_ALLOC) != 0)
339         return false;
340       if (&Sec == Obj.SectionNames)
341         return false;
342       switch (Sec.Type) {
343       case SHT_SYMTAB:
344       case SHT_REL:
345       case SHT_RELA:
346       case SHT_STRTAB:
347         return true;
348       }
349       return Sec.Name.startswith(".debug");
350     };
351 
352   if (Config.StripSections) {
353     RemovePred = [RemovePred](const SectionBase &Sec) {
354       return RemovePred(Sec) || (Sec.Flags & SHF_ALLOC) == 0;
355     };
356   }
357 
358   if (Config.StripDebug) {
359     RemovePred = [RemovePred](const SectionBase &Sec) {
360       return RemovePred(Sec) || Sec.Name.startswith(".debug");
361     };
362   }
363 
364   if (Config.StripNonAlloc)
365     RemovePred = [RemovePred, &Obj](const SectionBase &Sec) {
366       if (RemovePred(Sec))
367         return true;
368       if (&Sec == Obj.SectionNames)
369         return false;
370       return (Sec.Flags & SHF_ALLOC) == 0;
371     };
372 
373   if (Config.StripAll)
374     RemovePred = [RemovePred, &Obj](const SectionBase &Sec) {
375       if (RemovePred(Sec))
376         return true;
377       if (&Sec == Obj.SectionNames)
378         return false;
379       if (Sec.Name.startswith(".gnu.warning"))
380         return false;
381       return (Sec.Flags & SHF_ALLOC) == 0;
382     };
383 
384   // Explicit copies:
385   if (!Config.OnlyKeep.empty()) {
386     RemovePred = [&Config, RemovePred, &Obj](const SectionBase &Sec) {
387       // Explicitly keep these sections regardless of previous removes.
388       if (std::find(std::begin(Config.OnlyKeep), std::end(Config.OnlyKeep),
389                     Sec.Name) != std::end(Config.OnlyKeep))
390         return false;
391 
392       // Allow all implicit removes.
393       if (RemovePred(Sec))
394         return true;
395 
396       // Keep special sections.
397       if (Obj.SectionNames == &Sec)
398         return false;
399       if (Obj.SymbolTable == &Sec || Obj.SymbolTable->getStrTab() == &Sec)
400         return false;
401 
402       // Remove everything else.
403       return true;
404     };
405   }
406 
407   if (!Config.Keep.empty()) {
408     RemovePred = [Config, RemovePred](const SectionBase &Sec) {
409       // Explicitly keep these sections regardless of previous removes.
410       if (std::find(std::begin(Config.Keep), std::end(Config.Keep), Sec.Name) !=
411           std::end(Config.Keep))
412         return false;
413       // Otherwise defer to RemovePred.
414       return RemovePred(Sec);
415     };
416   }
417 
418   // This has to be the last predicate assignment.
419   // If the option --keep-symbol has been specified
420   // and at least one of those symbols is present
421   // (equivalently, the updated symbol table is not empty)
422   // the symbol table and the string table should not be removed.
423   if ((!Config.SymbolsToKeep.empty() || Config.KeepFileSymbols) &&
424       !Obj.SymbolTable->empty()) {
425     RemovePred = [&Obj, RemovePred](const SectionBase &Sec) {
426       if (&Sec == Obj.SymbolTable || &Sec == Obj.SymbolTable->getStrTab())
427         return false;
428       return RemovePred(Sec);
429     };
430   }
431 
432   Obj.removeSections(RemovePred);
433 
434   if (!Config.SectionsToRename.empty()) {
435     for (auto &Sec : Obj.sections()) {
436       const auto Iter = Config.SectionsToRename.find(Sec.Name);
437       if (Iter != Config.SectionsToRename.end())
438         Sec.Name = Iter->second;
439     }
440   }
441 
442   if (!Config.AddSection.empty()) {
443     for (const auto &Flag : Config.AddSection) {
444       auto SecPair = Flag.split("=");
445       auto SecName = SecPair.first;
446       auto File = SecPair.second;
447       auto BufOrErr = MemoryBuffer::getFile(File);
448       if (!BufOrErr)
449         reportError(File, BufOrErr.getError());
450       auto Buf = std::move(*BufOrErr);
451       auto BufPtr = reinterpret_cast<const uint8_t *>(Buf->getBufferStart());
452       auto BufSize = Buf->getBufferSize();
453       Obj.addSection<OwnedDataSection>(SecName,
454                                        ArrayRef<uint8_t>(BufPtr, BufSize));
455     }
456   }
457 
458   if (!Config.AddGnuDebugLink.empty())
459     Obj.addSection<GnuDebugLinkSection>(Config.AddGnuDebugLink);
460 }
461 
462 static void ExecuteElfObjcopyOnBinary(const CopyConfig &Config, Binary &Binary,
463                                       Buffer &Out) {
464   ELFReader Reader(&Binary);
465   std::unique_ptr<Object> Obj = Reader.create();
466 
467   HandleArgs(Config, *Obj, Reader, Reader.getElfType());
468 
469   std::unique_ptr<Writer> Writer =
470       CreateWriter(Config, *Obj, Out, Reader.getElfType());
471   Writer->finalize();
472   Writer->write();
473 }
474 
475 // For regular archives this function simply calls llvm::writeArchive,
476 // For thin archives it writes the archive file itself as well as its members.
477 static Error deepWriteArchive(StringRef ArcName,
478                               ArrayRef<NewArchiveMember> NewMembers,
479                               bool WriteSymtab, object::Archive::Kind Kind,
480                               bool Deterministic, bool Thin) {
481   Error E =
482       writeArchive(ArcName, NewMembers, WriteSymtab, Kind, Deterministic, Thin);
483   if (!Thin || E)
484     return E;
485   for (const NewArchiveMember &Member : NewMembers) {
486     // Internally, FileBuffer will use the buffer created by
487     // FileOutputBuffer::create, for regular files (that is the case for
488     // deepWriteArchive) FileOutputBuffer::create will return OnDiskBuffer.
489     // OnDiskBuffer uses a temporary file and then renames it. So in reality
490     // there is no inefficiency / duplicated in-memory buffers in this case. For
491     // now in-memory buffers can not be completely avoided since
492     // NewArchiveMember still requires them even though writeArchive does not
493     // write them on disk.
494     FileBuffer FB(Member.MemberName);
495     FB.allocate(Member.Buf->getBufferSize());
496     std::copy(Member.Buf->getBufferStart(), Member.Buf->getBufferEnd(),
497               FB.getBufferStart());
498     if (auto E = FB.commit())
499       return E;
500   }
501   return Error::success();
502 }
503 
504 static void ExecuteElfObjcopyOnArchive(const CopyConfig &Config, const Archive &Ar) {
505   std::vector<NewArchiveMember> NewArchiveMembers;
506   Error Err = Error::success();
507   for (const Archive::Child &Child : Ar.children(Err)) {
508     Expected<std::unique_ptr<Binary>> ChildOrErr = Child.getAsBinary();
509     if (!ChildOrErr)
510       reportError(Ar.getFileName(), ChildOrErr.takeError());
511     Expected<StringRef> ChildNameOrErr = Child.getName();
512     if (!ChildNameOrErr)
513       reportError(Ar.getFileName(), ChildNameOrErr.takeError());
514 
515     MemBuffer MB(ChildNameOrErr.get());
516     ExecuteElfObjcopyOnBinary(Config, **ChildOrErr, MB);
517 
518     Expected<NewArchiveMember> Member =
519         NewArchiveMember::getOldMember(Child, true);
520     if (!Member)
521       reportError(Ar.getFileName(), Member.takeError());
522     Member->Buf = MB.releaseMemoryBuffer();
523     Member->MemberName = Member->Buf->getBufferIdentifier();
524     NewArchiveMembers.push_back(std::move(*Member));
525   }
526 
527   if (Err)
528     reportError(Config.InputFilename, std::move(Err));
529   if (Error E =
530           deepWriteArchive(Config.OutputFilename, NewArchiveMembers,
531                            Ar.hasSymbolTable(), Ar.kind(), true, Ar.isThin()))
532     reportError(Config.OutputFilename, std::move(E));
533 }
534 
535 static void ExecuteElfObjcopy(const CopyConfig &Config) {
536   Expected<OwningBinary<llvm::object::Binary>> BinaryOrErr =
537       createBinary(Config.InputFilename);
538   if (!BinaryOrErr)
539     reportError(Config.InputFilename, BinaryOrErr.takeError());
540 
541   if (Archive *Ar = dyn_cast<Archive>(BinaryOrErr.get().getBinary()))
542     return ExecuteElfObjcopyOnArchive(Config, *Ar);
543 
544   FileBuffer FB(Config.OutputFilename);
545   ExecuteElfObjcopyOnBinary(Config, *BinaryOrErr.get().getBinary(), FB);
546 }
547 
548 // ParseObjcopyOptions returns the config and sets the input arguments. If a
549 // help flag is set then ParseObjcopyOptions will print the help messege and
550 // exit.
551 static CopyConfig ParseObjcopyOptions(ArrayRef<const char *> ArgsArr) {
552   ObjcopyOptTable T;
553   unsigned MissingArgumentIndex, MissingArgumentCount;
554   llvm::opt::InputArgList InputArgs =
555       T.ParseArgs(ArgsArr, MissingArgumentIndex, MissingArgumentCount);
556 
557   if (InputArgs.size() == 0) {
558     T.PrintHelp(errs(), "llvm-objcopy <input> [ <output> ]", "objcopy tool");
559     exit(1);
560   }
561 
562   if (InputArgs.hasArg(OBJCOPY_help)) {
563     T.PrintHelp(outs(), "llvm-objcopy <input> [ <output> ]", "objcopy tool");
564     exit(0);
565   }
566 
567   SmallVector<const char *, 2> Positional;
568 
569   for (auto Arg : InputArgs.filtered(OBJCOPY_UNKNOWN))
570     error("unknown argument '" + Arg->getAsString(InputArgs) + "'");
571 
572   for (auto Arg : InputArgs.filtered(OBJCOPY_INPUT))
573     Positional.push_back(Arg->getValue());
574 
575   if (Positional.empty())
576     error("No input file specified");
577 
578   if (Positional.size() > 2)
579     error("Too many positional arguments");
580 
581   CopyConfig Config;
582   Config.InputFilename = Positional[0];
583   Config.OutputFilename = Positional[Positional.size() == 1 ? 0 : 1];
584   Config.InputFormat = InputArgs.getLastArgValue(OBJCOPY_input_target);
585   Config.OutputFormat = InputArgs.getLastArgValue(OBJCOPY_output_target);
586   Config.BinaryArch = InputArgs.getLastArgValue(OBJCOPY_binary_architecture);
587 
588   Config.SplitDWO = InputArgs.getLastArgValue(OBJCOPY_split_dwo);
589   Config.AddGnuDebugLink = InputArgs.getLastArgValue(OBJCOPY_add_gnu_debuglink);
590 
591   for (auto Arg : InputArgs.filtered(OBJCOPY_redefine_symbol)) {
592     if (!StringRef(Arg->getValue()).contains('='))
593       error("Bad format for --redefine-sym");
594     auto Old2New = StringRef(Arg->getValue()).split('=');
595     if (!Config.SymbolsToRename.insert(Old2New).second)
596       error("Multiple redefinition of symbol " + Old2New.first);
597   }
598 
599   for (auto Arg : InputArgs.filtered(OBJCOPY_rename_section)) {
600     if (!StringRef(Arg->getValue()).contains('='))
601       error("Bad format for --rename-section");
602     auto Old2New = StringRef(Arg->getValue()).split('=');
603     if (!Config.SectionsToRename.insert(Old2New).second)
604       error("Already have a section rename for " + Old2New.first);
605   }
606 
607   for (auto Arg : InputArgs.filtered(OBJCOPY_remove_section))
608     Config.ToRemove.push_back(Arg->getValue());
609   for (auto Arg : InputArgs.filtered(OBJCOPY_keep))
610     Config.Keep.push_back(Arg->getValue());
611   for (auto Arg : InputArgs.filtered(OBJCOPY_only_keep))
612     Config.OnlyKeep.push_back(Arg->getValue());
613   for (auto Arg : InputArgs.filtered(OBJCOPY_add_section))
614     Config.AddSection.push_back(Arg->getValue());
615   Config.StripAll = InputArgs.hasArg(OBJCOPY_strip_all);
616   Config.StripAllGNU = InputArgs.hasArg(OBJCOPY_strip_all_gnu);
617   Config.StripDebug = InputArgs.hasArg(OBJCOPY_strip_debug);
618   Config.StripDWO = InputArgs.hasArg(OBJCOPY_strip_dwo);
619   Config.StripSections = InputArgs.hasArg(OBJCOPY_strip_sections);
620   Config.StripNonAlloc = InputArgs.hasArg(OBJCOPY_strip_non_alloc);
621   Config.StripUnneeded = InputArgs.hasArg(OBJCOPY_strip_unneeded);
622   Config.ExtractDWO = InputArgs.hasArg(OBJCOPY_extract_dwo);
623   Config.LocalizeHidden = InputArgs.hasArg(OBJCOPY_localize_hidden);
624   Config.Weaken = InputArgs.hasArg(OBJCOPY_weaken);
625   Config.DiscardAll = InputArgs.hasArg(OBJCOPY_discard_all);
626   Config.OnlyKeepDebug = InputArgs.hasArg(OBJCOPY_only_keep_debug);
627   Config.KeepFileSymbols = InputArgs.hasArg(OBJCOPY_keep_file_symbols);
628   for (auto Arg : InputArgs.filtered(OBJCOPY_localize_symbol))
629     Config.SymbolsToLocalize.push_back(Arg->getValue());
630   for (auto Arg : InputArgs.filtered(OBJCOPY_globalize_symbol))
631     Config.SymbolsToGlobalize.push_back(Arg->getValue());
632   for (auto Arg : InputArgs.filtered(OBJCOPY_weaken_symbol))
633     Config.SymbolsToWeaken.push_back(Arg->getValue());
634   for (auto Arg : InputArgs.filtered(OBJCOPY_strip_symbol))
635     Config.SymbolsToRemove.push_back(Arg->getValue());
636   for (auto Arg : InputArgs.filtered(OBJCOPY_keep_symbol))
637     Config.SymbolsToKeep.push_back(Arg->getValue());
638 
639   return Config;
640 }
641 
642 // ParseStripOptions returns the config and sets the input arguments. If a
643 // help flag is set then ParseStripOptions will print the help messege and
644 // exit.
645 static CopyConfig ParseStripOptions(ArrayRef<const char *> ArgsArr) {
646   StripOptTable T;
647   unsigned MissingArgumentIndex, MissingArgumentCount;
648   llvm::opt::InputArgList InputArgs =
649       T.ParseArgs(ArgsArr, MissingArgumentIndex, MissingArgumentCount);
650 
651   if (InputArgs.size() == 0) {
652     T.PrintHelp(errs(), "llvm-strip <input> [ <output> ]", "strip tool");
653     exit(1);
654   }
655 
656   if (InputArgs.hasArg(STRIP_help)) {
657     T.PrintHelp(outs(), "llvm-strip <input> [ <output> ]", "strip tool");
658     exit(0);
659   }
660 
661   SmallVector<const char *, 2> Positional;
662   for (auto Arg : InputArgs.filtered(STRIP_UNKNOWN))
663     error("unknown argument '" + Arg->getAsString(InputArgs) + "'");
664   for (auto Arg : InputArgs.filtered(STRIP_INPUT))
665     Positional.push_back(Arg->getValue());
666 
667   if (Positional.empty())
668     error("No input file specified");
669 
670   if (Positional.size() > 2)
671     error("Support for multiple input files is not implemented yet");
672 
673   CopyConfig Config;
674   Config.InputFilename = Positional[0];
675   Config.OutputFilename =
676       InputArgs.getLastArgValue(STRIP_output, Positional[0]);
677 
678   Config.StripDebug = InputArgs.hasArg(STRIP_strip_debug);
679 
680   Config.DiscardAll = InputArgs.hasArg(STRIP_discard_all);
681   Config.StripUnneeded = InputArgs.hasArg(STRIP_strip_unneeded);
682   Config.StripAll = InputArgs.hasArg(STRIP_strip_all);
683 
684   if (!Config.StripDebug && !Config.StripUnneeded && !Config.DiscardAll)
685     Config.StripAll = true;
686 
687   for (auto Arg : InputArgs.filtered(STRIP_remove_section))
688     Config.ToRemove.push_back(Arg->getValue());
689 
690   for (auto Arg : InputArgs.filtered(STRIP_keep_symbol))
691     Config.SymbolsToKeep.push_back(Arg->getValue());
692 
693   return Config;
694 }
695 
696 int main(int argc, char **argv) {
697   InitLLVM X(argc, argv);
698   ToolName = argv[0];
699   CopyConfig Config;
700   if (sys::path::stem(ToolName).endswith_lower("strip"))
701     Config = ParseStripOptions(makeArrayRef(argv + 1, argc));
702   else
703     Config = ParseObjcopyOptions(makeArrayRef(argv + 1, argc));
704   ExecuteElfObjcopy(Config);
705 }
706