llvm-ar.cpp revision 327952 
1//===-- llvm-ar.cpp - LLVM archive librarian utility ----------------------===//
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// Builds up (relatively) standard unix archive files (.a) containing LLVM
11// bitcode or other files.
12//
13//===----------------------------------------------------------------------===//
14
15#include "llvm/ADT/StringSwitch.h"
16#include "llvm/ADT/Triple.h"
17#include "llvm/IR/LLVMContext.h"
18#include "llvm/ToolDrivers/llvm-dlltool/DlltoolDriver.h"
19#include "llvm/ToolDrivers/llvm-lib/LibDriver.h"
20#include "llvm/Object/Archive.h"
21#include "llvm/Object/ArchiveWriter.h"
22#include "llvm/Object/MachO.h"
23#include "llvm/Object/ObjectFile.h"
24#include "llvm/Support/Chrono.h"
25#include "llvm/Support/CommandLine.h"
26#include "llvm/Support/Errc.h"
27#include "llvm/Support/FileSystem.h"
28#include "llvm/Support/Format.h"
29#include "llvm/Support/LineIterator.h"
30#include "llvm/Support/ManagedStatic.h"
31#include "llvm/Support/MemoryBuffer.h"
32#include "llvm/Support/Path.h"
33#include "llvm/Support/PrettyStackTrace.h"
34#include "llvm/Support/Signals.h"
35#include "llvm/Support/TargetSelect.h"
36#include "llvm/Support/ToolOutputFile.h"
37#include "llvm/Support/raw_ostream.h"
38
39#if !defined(_MSC_VER) && !defined(__MINGW32__)
40#include <unistd.h>
41#else
42#include <io.h>
43#endif
44
45using namespace llvm;
46
47// The name this program was invoked as.
48static StringRef ToolName;
49
50// Show the error message and exit.
51LLVM_ATTRIBUTE_NORETURN static void fail(Twine Error) {
52  errs() << ToolName << ": " << Error << ".\n";
53  cl::PrintHelpMessage();
54  exit(1);
55}
56
57static void failIfError(std::error_code EC, Twine Context = "") {
58  if (!EC)
59    return;
60
61  std::string ContextStr = Context.str();
62  if (ContextStr == "")
63    fail(EC.message());
64  fail(Context + ": " + EC.message());
65}
66
67static void failIfError(Error E, Twine Context = "") {
68  if (!E)
69    return;
70
71  handleAllErrors(std::move(E), [&](const llvm::ErrorInfoBase &EIB) {
72    std::string ContextStr = Context.str();
73    if (ContextStr == "")
74      fail(EIB.message());
75    fail(Context + ": " + EIB.message());
76  });
77}
78
79// llvm-ar/llvm-ranlib remaining positional arguments.
80static cl::list<std::string>
81    RestOfArgs(cl::Positional, cl::ZeroOrMore,
82               cl::desc("[relpos] [count] <archive-file> [members]..."));
83
84static cl::opt<bool> MRI("M", cl::desc(""));
85static cl::opt<std::string> Plugin("plugin", cl::desc("plugin (ignored for compatibility"));
86
87namespace {
88enum Format { Default, GNU, BSD, DARWIN };
89}
90
91static cl::opt<Format>
92    FormatOpt("format", cl::desc("Archive format to create"),
93              cl::values(clEnumValN(Default, "default", "default"),
94                         clEnumValN(GNU, "gnu", "gnu"),
95                         clEnumValN(DARWIN, "darwin", "darwin"),
96                         clEnumValN(BSD, "bsd", "bsd")));
97
98static std::string Options;
99
100// Provide additional help output explaining the operations and modifiers of
101// llvm-ar. This object instructs the CommandLine library to print the text of
102// the constructor when the --help option is given.
103static cl::extrahelp MoreHelp(
104  "\nOPERATIONS:\n"
105  "  d[NsS]       - delete file(s) from the archive\n"
106  "  m[abiSs]     - move file(s) in the archive\n"
107  "  p[kN]        - print file(s) found in the archive\n"
108  "  q[ufsS]      - quick append file(s) to the archive\n"
109  "  r[abfiuRsS]  - replace or insert file(s) into the archive\n"
110  "  t            - display contents of archive\n"
111  "  x[No]        - extract file(s) from the archive\n"
112  "\nMODIFIERS (operation specific):\n"
113  "  [a] - put file(s) after [relpos]\n"
114  "  [b] - put file(s) before [relpos] (same as [i])\n"
115  "  [i] - put file(s) before [relpos] (same as [b])\n"
116  "  [o] - preserve original dates\n"
117  "  [s] - create an archive index (cf. ranlib)\n"
118  "  [S] - do not build a symbol table\n"
119  "  [T] - create a thin archive\n"
120  "  [u] - update only files newer than archive contents\n"
121  "\nMODIFIERS (generic):\n"
122  "  [c] - do not warn if the library had to be created\n"
123  "  [v] - be verbose about actions taken\n"
124);
125
126static const char OptionChars[] = "dmpqrtxabiosSTucv";
127
128// This enumeration delineates the kinds of operations on an archive
129// that are permitted.
130enum ArchiveOperation {
131  Print,            ///< Print the contents of the archive
132  Delete,           ///< Delete the specified members
133  Move,             ///< Move members to end or as given by {a,b,i} modifiers
134  QuickAppend,      ///< Quickly append to end of archive
135  ReplaceOrInsert,  ///< Replace or Insert members
136  DisplayTable,     ///< Display the table of contents
137  Extract,          ///< Extract files back to file system
138  CreateSymTab      ///< Create a symbol table in an existing archive
139};
140
141// Modifiers to follow operation to vary behavior
142static bool AddAfter = false;      ///< 'a' modifier
143static bool AddBefore = false;     ///< 'b' modifier
144static bool Create = false;        ///< 'c' modifier
145static bool OriginalDates = false; ///< 'o' modifier
146static bool OnlyUpdate = false;    ///< 'u' modifier
147static bool Verbose = false;       ///< 'v' modifier
148static bool Symtab = true;         ///< 's' modifier
149static bool Deterministic = true;  ///< 'D' and 'U' modifiers
150static bool Thin = false;          ///< 'T' modifier
151
152// Relative Positional Argument (for insert/move). This variable holds
153// the name of the archive member to which the 'a', 'b' or 'i' modifier
154// refers. Only one of 'a', 'b' or 'i' can be specified so we only need
155// one variable.
156static std::string RelPos;
157
158// This variable holds the name of the archive file as given on the
159// command line.
160static std::string ArchiveName;
161
162// This variable holds the list of member files to proecess, as given
163// on the command line.
164static std::vector<StringRef> Members;
165
166// Extract the member filename from the command line for the [relpos] argument
167// associated with a, b, and i modifiers
168static void getRelPos() {
169  if(RestOfArgs.size() == 0)
170    fail("Expected [relpos] for a, b, or i modifier");
171  RelPos = RestOfArgs[0];
172  RestOfArgs.erase(RestOfArgs.begin());
173}
174
175static void getOptions() {
176  if(RestOfArgs.size() == 0)
177    fail("Expected options");
178  Options = RestOfArgs[0];
179  RestOfArgs.erase(RestOfArgs.begin());
180}
181
182// Get the archive file name from the command line
183static void getArchive() {
184  if(RestOfArgs.size() == 0)
185    fail("An archive name must be specified");
186  ArchiveName = RestOfArgs[0];
187  RestOfArgs.erase(RestOfArgs.begin());
188}
189
190// Copy over remaining items in RestOfArgs to our Members vector
191static void getMembers() {
192  for (auto &Arg : RestOfArgs)
193    Members.push_back(Arg);
194}
195
196static void runMRIScript();
197
198// Parse the command line options as presented and return the operation
199// specified. Process all modifiers and check to make sure that constraints on
200// modifier/operation pairs have not been violated.
201static ArchiveOperation parseCommandLine() {
202  if (MRI) {
203    if (!RestOfArgs.empty())
204      fail("Cannot mix -M and other options");
205    runMRIScript();
206  }
207
208  getOptions();
209
210  // Keep track of number of operations. We can only specify one
211  // per execution.
212  unsigned NumOperations = 0;
213
214  // Keep track of the number of positional modifiers (a,b,i). Only
215  // one can be specified.
216  unsigned NumPositional = 0;
217
218  // Keep track of which operation was requested
219  ArchiveOperation Operation;
220
221  bool MaybeJustCreateSymTab = false;
222
223  for(unsigned i=0; i<Options.size(); ++i) {
224    switch(Options[i]) {
225    case 'd': ++NumOperations; Operation = Delete; break;
226    case 'm': ++NumOperations; Operation = Move ; break;
227    case 'p': ++NumOperations; Operation = Print; break;
228    case 'q': ++NumOperations; Operation = QuickAppend; break;
229    case 'r': ++NumOperations; Operation = ReplaceOrInsert; break;
230    case 't': ++NumOperations; Operation = DisplayTable; break;
231    case 'x': ++NumOperations; Operation = Extract; break;
232    case 'c': Create = true; break;
233    case 'l': /* accepted but unused */ break;
234    case 'o': OriginalDates = true; break;
235    case 's':
236      Symtab = true;
237      MaybeJustCreateSymTab = true;
238      break;
239    case 'S':
240      Symtab = false;
241      break;
242    case 'u': OnlyUpdate = true; break;
243    case 'v': Verbose = true; break;
244    case 'a':
245      getRelPos();
246      AddAfter = true;
247      NumPositional++;
248      break;
249    case 'b':
250      getRelPos();
251      AddBefore = true;
252      NumPositional++;
253      break;
254    case 'i':
255      getRelPos();
256      AddBefore = true;
257      NumPositional++;
258      break;
259    case 'D':
260      Deterministic = true;
261      break;
262    case 'U':
263      Deterministic = false;
264      break;
265    case 'T':
266      Thin = true;
267      break;
268    default:
269      fail(std::string("unknown option ") + Options[i]);
270    }
271  }
272
273  // At this point, the next thing on the command line must be
274  // the archive name.
275  getArchive();
276
277  // Everything on the command line at this point is a member.
278  getMembers();
279
280 if (NumOperations == 0 && MaybeJustCreateSymTab) {
281    NumOperations = 1;
282    Operation = CreateSymTab;
283    if (!Members.empty())
284      fail("The s operation takes only an archive as argument");
285  }
286
287  // Perform various checks on the operation/modifier specification
288  // to make sure we are dealing with a legal request.
289  if (NumOperations == 0)
290    fail("You must specify at least one of the operations");
291  if (NumOperations > 1)
292    fail("Only one operation may be specified");
293  if (NumPositional > 1)
294    fail("You may only specify one of a, b, and i modifiers");
295  if (AddAfter || AddBefore) {
296    if (Operation != Move && Operation != ReplaceOrInsert)
297      fail("The 'a', 'b' and 'i' modifiers can only be specified with "
298           "the 'm' or 'r' operations");
299  }
300  if (OriginalDates && Operation != Extract)
301    fail("The 'o' modifier is only applicable to the 'x' operation");
302  if (OnlyUpdate && Operation != ReplaceOrInsert)
303    fail("The 'u' modifier is only applicable to the 'r' operation");
304
305  // Return the parsed operation to the caller
306  return Operation;
307}
308
309// Implements the 'p' operation. This function traverses the archive
310// looking for members that match the path list.
311static void doPrint(StringRef Name, const object::Archive::Child &C) {
312  if (Verbose)
313    outs() << "Printing " << Name << "\n";
314
315  Expected<StringRef> DataOrErr = C.getBuffer();
316  failIfError(DataOrErr.takeError());
317  StringRef Data = *DataOrErr;
318  outs().write(Data.data(), Data.size());
319}
320
321// Utility function for printing out the file mode when the 't' operation is in
322// verbose mode.
323static void printMode(unsigned mode) {
324  outs() << ((mode & 004) ? "r" : "-");
325  outs() << ((mode & 002) ? "w" : "-");
326  outs() << ((mode & 001) ? "x" : "-");
327}
328
329// Implement the 't' operation. This function prints out just
330// the file names of each of the members. However, if verbose mode is requested
331// ('v' modifier) then the file type, permission mode, user, group, size, and
332// modification time are also printed.
333static void doDisplayTable(StringRef Name, const object::Archive::Child &C) {
334  if (Verbose) {
335    Expected<sys::fs::perms> ModeOrErr = C.getAccessMode();
336    failIfError(ModeOrErr.takeError());
337    sys::fs::perms Mode = ModeOrErr.get();
338    printMode((Mode >> 6) & 007);
339    printMode((Mode >> 3) & 007);
340    printMode(Mode & 007);
341    Expected<unsigned> UIDOrErr = C.getUID();
342    failIfError(UIDOrErr.takeError());
343    outs() << ' ' << UIDOrErr.get();
344    Expected<unsigned> GIDOrErr = C.getGID();
345    failIfError(GIDOrErr.takeError());
346    outs() << '/' << GIDOrErr.get();
347    Expected<uint64_t> Size = C.getSize();
348    failIfError(Size.takeError());
349    outs() << ' ' << format("%6llu", Size.get());
350    auto ModTimeOrErr = C.getLastModified();
351    failIfError(ModTimeOrErr.takeError());
352    outs() << ' ' << ModTimeOrErr.get();
353    outs() << ' ';
354  }
355
356  if (C.getParent()->isThin()) {
357    outs() << sys::path::parent_path(ArchiveName);
358    outs() << '/';
359  }
360  outs() << Name << "\n";
361}
362
363// Implement the 'x' operation. This function extracts files back to the file
364// system.
365static void doExtract(StringRef Name, const object::Archive::Child &C) {
366  // Retain the original mode.
367  Expected<sys::fs::perms> ModeOrErr = C.getAccessMode();
368  failIfError(ModeOrErr.takeError());
369  sys::fs::perms Mode = ModeOrErr.get();
370
371  int FD;
372  failIfError(sys::fs::openFileForWrite(sys::path::filename(Name), FD,
373                                        sys::fs::F_None, Mode),
374              Name);
375
376  {
377    raw_fd_ostream file(FD, false);
378
379    // Get the data and its length
380    Expected<StringRef> BufOrErr = C.getBuffer();
381    failIfError(BufOrErr.takeError());
382    StringRef Data = BufOrErr.get();
383
384    // Write the data.
385    file.write(Data.data(), Data.size());
386  }
387
388  // If we're supposed to retain the original modification times, etc. do so
389  // now.
390  if (OriginalDates) {
391    auto ModTimeOrErr = C.getLastModified();
392    failIfError(ModTimeOrErr.takeError());
393    failIfError(
394        sys::fs::setLastModificationAndAccessTime(FD, ModTimeOrErr.get()));
395  }
396
397  if (close(FD))
398    fail("Could not close the file");
399}
400
401static bool shouldCreateArchive(ArchiveOperation Op) {
402  switch (Op) {
403  case Print:
404  case Delete:
405  case Move:
406  case DisplayTable:
407  case Extract:
408  case CreateSymTab:
409    return false;
410
411  case QuickAppend:
412  case ReplaceOrInsert:
413    return true;
414  }
415
416  llvm_unreachable("Missing entry in covered switch.");
417}
418
419static void performReadOperation(ArchiveOperation Operation,
420                                 object::Archive *OldArchive) {
421  if (Operation == Extract && OldArchive->isThin())
422    fail("extracting from a thin archive is not supported");
423
424  bool Filter = !Members.empty();
425  {
426    Error Err = Error::success();
427    for (auto &C : OldArchive->children(Err)) {
428      Expected<StringRef> NameOrErr = C.getName();
429      failIfError(NameOrErr.takeError());
430      StringRef Name = NameOrErr.get();
431
432      if (Filter) {
433        auto I = find(Members, Name);
434        if (I == Members.end())
435          continue;
436        Members.erase(I);
437      }
438
439      switch (Operation) {
440      default:
441        llvm_unreachable("Not a read operation");
442      case Print:
443        doPrint(Name, C);
444        break;
445      case DisplayTable:
446        doDisplayTable(Name, C);
447        break;
448      case Extract:
449        doExtract(Name, C);
450        break;
451      }
452    }
453    failIfError(std::move(Err));
454  }
455
456  if (Members.empty())
457    return;
458  for (StringRef Name : Members)
459    errs() << Name << " was not found\n";
460  exit(1);
461}
462
463static void addMember(std::vector<NewArchiveMember> &Members,
464                      StringRef FileName, int Pos = -1) {
465  Expected<NewArchiveMember> NMOrErr =
466      NewArchiveMember::getFile(FileName, Deterministic);
467  failIfError(NMOrErr.takeError(), FileName);
468
469  // Use the basename of the object path for the member name.
470  NMOrErr->MemberName = sys::path::filename(NMOrErr->MemberName);
471
472  if (Pos == -1)
473    Members.push_back(std::move(*NMOrErr));
474  else
475    Members[Pos] = std::move(*NMOrErr);
476}
477
478static void addMember(std::vector<NewArchiveMember> &Members,
479                      const object::Archive::Child &M, int Pos = -1) {
480  if (Thin && !M.getParent()->isThin())
481    fail("Cannot convert a regular archive to a thin one");
482  Expected<NewArchiveMember> NMOrErr =
483      NewArchiveMember::getOldMember(M, Deterministic);
484  failIfError(NMOrErr.takeError());
485  if (Pos == -1)
486    Members.push_back(std::move(*NMOrErr));
487  else
488    Members[Pos] = std::move(*NMOrErr);
489}
490
491enum InsertAction {
492  IA_AddOldMember,
493  IA_AddNewMember,
494  IA_Delete,
495  IA_MoveOldMember,
496  IA_MoveNewMember
497};
498
499static InsertAction computeInsertAction(ArchiveOperation Operation,
500                                        const object::Archive::Child &Member,
501                                        StringRef Name,
502                                        std::vector<StringRef>::iterator &Pos) {
503  if (Operation == QuickAppend || Members.empty())
504    return IA_AddOldMember;
505
506  auto MI = find_if(Members, [Name](StringRef Path) {
507    return Name == sys::path::filename(Path);
508  });
509
510  if (MI == Members.end())
511    return IA_AddOldMember;
512
513  Pos = MI;
514
515  if (Operation == Delete)
516    return IA_Delete;
517
518  if (Operation == Move)
519    return IA_MoveOldMember;
520
521  if (Operation == ReplaceOrInsert) {
522    StringRef PosName = sys::path::filename(RelPos);
523    if (!OnlyUpdate) {
524      if (PosName.empty())
525        return IA_AddNewMember;
526      return IA_MoveNewMember;
527    }
528
529    // We could try to optimize this to a fstat, but it is not a common
530    // operation.
531    sys::fs::file_status Status;
532    failIfError(sys::fs::status(*MI, Status), *MI);
533    auto ModTimeOrErr = Member.getLastModified();
534    failIfError(ModTimeOrErr.takeError());
535    if (Status.getLastModificationTime() < ModTimeOrErr.get()) {
536      if (PosName.empty())
537        return IA_AddOldMember;
538      return IA_MoveOldMember;
539    }
540
541    if (PosName.empty())
542      return IA_AddNewMember;
543    return IA_MoveNewMember;
544  }
545  llvm_unreachable("No such operation");
546}
547
548// We have to walk this twice and computing it is not trivial, so creating an
549// explicit std::vector is actually fairly efficient.
550static std::vector<NewArchiveMember>
551computeNewArchiveMembers(ArchiveOperation Operation,
552                         object::Archive *OldArchive) {
553  std::vector<NewArchiveMember> Ret;
554  std::vector<NewArchiveMember> Moved;
555  int InsertPos = -1;
556  StringRef PosName = sys::path::filename(RelPos);
557  if (OldArchive) {
558    Error Err = Error::success();
559    for (auto &Child : OldArchive->children(Err)) {
560      int Pos = Ret.size();
561      Expected<StringRef> NameOrErr = Child.getName();
562      failIfError(NameOrErr.takeError());
563      StringRef Name = NameOrErr.get();
564      if (Name == PosName) {
565        assert(AddAfter || AddBefore);
566        if (AddBefore)
567          InsertPos = Pos;
568        else
569          InsertPos = Pos + 1;
570      }
571
572      std::vector<StringRef>::iterator MemberI = Members.end();
573      InsertAction Action =
574          computeInsertAction(Operation, Child, Name, MemberI);
575      switch (Action) {
576      case IA_AddOldMember:
577        addMember(Ret, Child);
578        break;
579      case IA_AddNewMember:
580        addMember(Ret, *MemberI);
581        break;
582      case IA_Delete:
583        break;
584      case IA_MoveOldMember:
585        addMember(Moved, Child);
586        break;
587      case IA_MoveNewMember:
588        addMember(Moved, *MemberI);
589        break;
590      }
591      if (MemberI != Members.end())
592        Members.erase(MemberI);
593    }
594    failIfError(std::move(Err));
595  }
596
597  if (Operation == Delete)
598    return Ret;
599
600  if (!RelPos.empty() && InsertPos == -1)
601    fail("Insertion point not found");
602
603  if (RelPos.empty())
604    InsertPos = Ret.size();
605
606  assert(unsigned(InsertPos) <= Ret.size());
607  int Pos = InsertPos;
608  for (auto &M : Moved) {
609    Ret.insert(Ret.begin() + Pos, std::move(M));
610    ++Pos;
611  }
612
613  for (unsigned I = 0; I != Members.size(); ++I)
614    Ret.insert(Ret.begin() + InsertPos, NewArchiveMember());
615  Pos = InsertPos;
616  for (auto &Member : Members) {
617    addMember(Ret, Member, Pos);
618    ++Pos;
619  }
620
621  return Ret;
622}
623
624static object::Archive::Kind getDefaultForHost() {
625  return Triple(sys::getProcessTriple()).isOSDarwin()
626             ? object::Archive::K_DARWIN
627             : object::Archive::K_GNU;
628}
629
630static object::Archive::Kind getKindFromMember(const NewArchiveMember &Member) {
631  Expected<std::unique_ptr<object::ObjectFile>> OptionalObject =
632      object::ObjectFile::createObjectFile(Member.Buf->getMemBufferRef());
633
634  if (OptionalObject)
635    return isa<object::MachOObjectFile>(**OptionalObject)
636               ? object::Archive::K_DARWIN
637               : object::Archive::K_GNU;
638
639  // squelch the error in case we had a non-object file
640  consumeError(OptionalObject.takeError());
641  return getDefaultForHost();
642}
643
644static void
645performWriteOperation(ArchiveOperation Operation,
646                      object::Archive *OldArchive,
647                      std::unique_ptr<MemoryBuffer> OldArchiveBuf,
648                      std::vector<NewArchiveMember> *NewMembersP) {
649  std::vector<NewArchiveMember> NewMembers;
650  if (!NewMembersP)
651    NewMembers = computeNewArchiveMembers(Operation, OldArchive);
652
653  object::Archive::Kind Kind;
654  switch (FormatOpt) {
655  case Default:
656    if (Thin)
657      Kind = object::Archive::K_GNU;
658    else if (OldArchive)
659      Kind = OldArchive->kind();
660    else if (NewMembersP)
661      Kind = NewMembersP->size() ? getKindFromMember(NewMembersP->front())
662                                 : getDefaultForHost();
663    else
664      Kind = NewMembers.size() ? getKindFromMember(NewMembers.front())
665                               : getDefaultForHost();
666    break;
667  case GNU:
668    Kind = object::Archive::K_GNU;
669    break;
670  case BSD:
671    if (Thin)
672      fail("Only the gnu format has a thin mode");
673    Kind = object::Archive::K_BSD;
674    break;
675  case DARWIN:
676    if (Thin)
677      fail("Only the gnu format has a thin mode");
678    Kind = object::Archive::K_DARWIN;
679    break;
680  }
681
682  Error E =
683      writeArchive(ArchiveName, NewMembersP ? *NewMembersP : NewMembers, Symtab,
684                   Kind, Deterministic, Thin, std::move(OldArchiveBuf));
685  failIfError(std::move(E), ArchiveName);
686}
687
688static void createSymbolTable(object::Archive *OldArchive) {
689  // When an archive is created or modified, if the s option is given, the
690  // resulting archive will have a current symbol table. If the S option
691  // is given, it will have no symbol table.
692  // In summary, we only need to update the symbol table if we have none.
693  // This is actually very common because of broken build systems that think
694  // they have to run ranlib.
695  if (OldArchive->hasSymbolTable())
696    return;
697
698  performWriteOperation(CreateSymTab, OldArchive, nullptr, nullptr);
699}
700
701static void performOperation(ArchiveOperation Operation,
702                             object::Archive *OldArchive,
703                             std::unique_ptr<MemoryBuffer> OldArchiveBuf,
704                             std::vector<NewArchiveMember> *NewMembers) {
705  switch (Operation) {
706  case Print:
707  case DisplayTable:
708  case Extract:
709    performReadOperation(Operation, OldArchive);
710    return;
711
712  case Delete:
713  case Move:
714  case QuickAppend:
715  case ReplaceOrInsert:
716    performWriteOperation(Operation, OldArchive, std::move(OldArchiveBuf),
717                          NewMembers);
718    return;
719  case CreateSymTab:
720    createSymbolTable(OldArchive);
721    return;
722  }
723  llvm_unreachable("Unknown operation.");
724}
725
726static int performOperation(ArchiveOperation Operation,
727                            std::vector<NewArchiveMember> *NewMembers) {
728  // Create or open the archive object.
729  ErrorOr<std::unique_ptr<MemoryBuffer>> Buf =
730      MemoryBuffer::getFile(ArchiveName, -1, false);
731  std::error_code EC = Buf.getError();
732  if (EC && EC != errc::no_such_file_or_directory)
733    fail("error opening '" + ArchiveName + "': " + EC.message() + "!");
734
735  if (!EC) {
736    Error Err = Error::success();
737    object::Archive Archive(Buf.get()->getMemBufferRef(), Err);
738    EC = errorToErrorCode(std::move(Err));
739    failIfError(EC,
740                "error loading '" + ArchiveName + "': " + EC.message() + "!");
741    performOperation(Operation, &Archive, std::move(Buf.get()), NewMembers);
742    return 0;
743  }
744
745  assert(EC == errc::no_such_file_or_directory);
746
747  if (!shouldCreateArchive(Operation)) {
748    failIfError(EC, Twine("error loading '") + ArchiveName + "'");
749  } else {
750    if (!Create) {
751      // Produce a warning if we should and we're creating the archive
752      errs() << ToolName << ": creating " << ArchiveName << "\n";
753    }
754  }
755
756  performOperation(Operation, nullptr, nullptr, NewMembers);
757  return 0;
758}
759
760static void runMRIScript() {
761  enum class MRICommand { AddLib, AddMod, Create, Save, End, Invalid };
762
763  ErrorOr<std::unique_ptr<MemoryBuffer>> Buf = MemoryBuffer::getSTDIN();
764  failIfError(Buf.getError());
765  const MemoryBuffer &Ref = *Buf.get();
766  bool Saved = false;
767  std::vector<NewArchiveMember> NewMembers;
768  std::vector<std::unique_ptr<MemoryBuffer>> ArchiveBuffers;
769  std::vector<std::unique_ptr<object::Archive>> Archives;
770
771  for (line_iterator I(Ref, /*SkipBlanks*/ true, ';'), E; I != E; ++I) {
772    StringRef Line = *I;
773    StringRef CommandStr, Rest;
774    std::tie(CommandStr, Rest) = Line.split(' ');
775    Rest = Rest.trim();
776    if (!Rest.empty() && Rest.front() == '"' && Rest.back() == '"')
777      Rest = Rest.drop_front().drop_back();
778    auto Command = StringSwitch<MRICommand>(CommandStr.lower())
779                       .Case("addlib", MRICommand::AddLib)
780                       .Case("addmod", MRICommand::AddMod)
781                       .Case("create", MRICommand::Create)
782                       .Case("save", MRICommand::Save)
783                       .Case("end", MRICommand::End)
784                       .Default(MRICommand::Invalid);
785
786    switch (Command) {
787    case MRICommand::AddLib: {
788      auto BufOrErr = MemoryBuffer::getFile(Rest, -1, false);
789      failIfError(BufOrErr.getError(), "Could not open library");
790      ArchiveBuffers.push_back(std::move(*BufOrErr));
791      auto LibOrErr =
792          object::Archive::create(ArchiveBuffers.back()->getMemBufferRef());
793      failIfError(errorToErrorCode(LibOrErr.takeError()),
794                  "Could not parse library");
795      Archives.push_back(std::move(*LibOrErr));
796      object::Archive &Lib = *Archives.back();
797      {
798        Error Err = Error::success();
799        for (auto &Member : Lib.children(Err))
800          addMember(NewMembers, Member);
801        failIfError(std::move(Err));
802      }
803      break;
804    }
805    case MRICommand::AddMod:
806      addMember(NewMembers, Rest);
807      break;
808    case MRICommand::Create:
809      Create = true;
810      if (!ArchiveName.empty())
811        fail("Editing multiple archives not supported");
812      if (Saved)
813        fail("File already saved");
814      ArchiveName = Rest;
815      break;
816    case MRICommand::Save:
817      Saved = true;
818      break;
819    case MRICommand::End:
820      break;
821    case MRICommand::Invalid:
822      fail("Unknown command: " + CommandStr);
823    }
824  }
825
826  // Nothing to do if not saved.
827  if (Saved)
828    performOperation(ReplaceOrInsert, &NewMembers);
829  exit(0);
830}
831
832static int ar_main() {
833  // Do our own parsing of the command line because the CommandLine utility
834  // can't handle the grouped positional parameters without a dash.
835  ArchiveOperation Operation = parseCommandLine();
836  return performOperation(Operation, nullptr);
837}
838
839static int ranlib_main() {
840  if (RestOfArgs.size() != 1)
841    fail(ToolName + " takes just one archive as an argument");
842  ArchiveName = RestOfArgs[0];
843  return performOperation(CreateSymTab, nullptr);
844}
845
846int main(int argc, char **argv) {
847  ToolName = argv[0];
848  // Print a stack trace if we signal out.
849  sys::PrintStackTraceOnErrorSignal(argv[0]);
850  PrettyStackTraceProgram X(argc, argv);
851  llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
852
853  llvm::InitializeAllTargetInfos();
854  llvm::InitializeAllTargetMCs();
855  llvm::InitializeAllAsmParsers();
856
857  StringRef Stem = sys::path::stem(ToolName);
858  if (Stem.find("dlltool") != StringRef::npos)
859    return dlltoolDriverMain(makeArrayRef(argv, argc));
860
861  if (Stem.find("ranlib") == StringRef::npos &&
862      Stem.find("lib") != StringRef::npos)
863    return libDriverMain(makeArrayRef(argv, argc));
864
865  for (int i = 1; i < argc; i++) {
866    // If an argument starts with a dash and only contains chars
867    // that belong to the options chars set, remove the dash.
868    // We can't handle it after the command line options parsing
869    // is done, since it will error out on an unrecognized string
870    // starting with a dash.
871    // Make sure this doesn't match the actual llvm-ar specific options
872    // that start with a dash.
873    StringRef S = argv[i];
874    if (S.startswith("-") &&
875        S.find_first_not_of(OptionChars, 1) == StringRef::npos) {
876      argv[i]++;
877      break;
878    }
879    if (S == "--")
880      break;
881  }
882
883  // Have the command line options parsed and handle things
884  // like --help and --version.
885  cl::ParseCommandLineOptions(argc, argv,
886    "LLVM Archiver (llvm-ar)\n\n"
887    "  This program archives bitcode files into single libraries\n"
888  );
889
890  if (Stem.find("ranlib") != StringRef::npos)
891    return ranlib_main();
892  if (Stem.find("ar") != StringRef::npos)
893    return ar_main();
894  fail("Not ranlib, ar, lib or dlltool!");
895}
896