tools/llvm-ar/llvm-ar.cpp

   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/Module.h"
  16 #include "llvm/Bitcode/Archive.h"
  17 #include "llvm/Support/CommandLine.h"
  18 #include "llvm/Support/ManagedStatic.h"
  19 #include "llvm/Support/PrettyStackTrace.h"
  20 #include "llvm/System/Signals.h"
  21 #include <iostream>
  22 #include <algorithm>
  23 #include <iomanip>
  24 #include <memory>
  25 using namespace llvm;
  26
  27 // Option for compatibility with AIX, not used but must allow it to be present.
  28 static cl::opt<bool>
  29 X32Option ("X32_64", cl::Hidden,
  30             cl::desc("Ignored option for compatibility with AIX"));
  31
  32 // llvm-ar operation code and modifier flags. This must come first.
  33 static cl::opt<std::string>
  34 Options(cl::Positional, cl::Required, cl::desc("{operation}[modifiers]..."));
  35
  36 // llvm-ar remaining positional arguments.
  37 static cl::list<std::string>
  38 RestOfArgs(cl::Positional, cl::OneOrMore,
  39     cl::desc("[relpos] [count] <archive-file> [members]..."));
  40
  41 // MoreHelp - Provide additional help output explaining the operations and
  42 // modifiers of llvm-ar. This object instructs the CommandLine library
  43 // to print the text of the constructor when the --help option is given.
  44 static cl::extrahelp MoreHelp(
  45   "\nOPERATIONS:\n"
  46   "  d[NsS]       - delete file(s) from the archive\n"
  47   "  m[abiSs]     - move file(s) in the archive\n"
  48   "  p[kN]        - print file(s) found in the archive\n"
  49   "  q[ufsS]      - quick append file(s) to the archive\n"
  50   "  r[abfiuzRsS] - replace or insert file(s) into the archive\n"
  51   "  t            - display contents of archive\n"
  52   "  x[No]        - extract file(s) from the archive\n"
  53   "\nMODIFIERS (operation specific):\n"
  54   "  [a] - put file(s) after [relpos]\n"
  55   "  [b] - put file(s) before [relpos] (same as [i])\n"
  56   "  [f] - truncate inserted file names\n"
  57   "  [i] - put file(s) before [relpos] (same as [b])\n"
  58   "  [k] - always print bitcode files (default is to skip them)\n"
  59   "  [N] - use instance [count] of name\n"
  60   "  [o] - preserve original dates\n"
  61   "  [P] - use full path names when matching\n"
  62   "  [R] - recurse through directories when inserting\n"
  63   "  [s] - create an archive index (cf. ranlib)\n"
  64   "  [S] - do not build a symbol table\n"
  65   "  [u] - update only files newer than archive contents\n"
  66   "  [z] - compress files before inserting/extracting\n"
  67   "\nMODIFIERS (generic):\n"
  68   "  [c] - do not warn if the library had to be created\n"
  69   "  [v] - be verbose about actions taken\n"
  70   "  [V] - be *really* verbose about actions taken\n"
  71 );
  72
  73 // This enumeration delineates the kinds of operations on an archive
  74 // that are permitted.
  75 enum ArchiveOperation {
  76   NoOperation,      ///< An operation hasn't been specified
  77   Print,            ///< Print the contents of the archive
  78   Delete,           ///< Delete the specified members
  79   Move,             ///< Move members to end or as given by {a,b,i} modifiers
  80   QuickAppend,      ///< Quickly append to end of archive
  81   ReplaceOrInsert,  ///< Replace or Insert members
  82   DisplayTable,     ///< Display the table of contents
  83   Extract           ///< Extract files back to file system
  84 };
  85
  86 // Modifiers to follow operation to vary behavior
  87 bool AddAfter = false;           ///< 'a' modifier
  88 bool AddBefore = false;          ///< 'b' modifier
  89 bool Create = false;             ///< 'c' modifier
  90 bool TruncateNames = false;      ///< 'f' modifier
  91 bool InsertBefore = false;       ///< 'i' modifier
  92 bool DontSkipBitcode = false;    ///< 'k' modifier
  93 bool UseCount = false;           ///< 'N' modifier
  94 bool OriginalDates = false;      ///< 'o' modifier
  95 bool FullPath = false;           ///< 'P' modifier
  96 bool RecurseDirectories = false; ///< 'R' modifier
  97 bool SymTable = true;            ///< 's' & 'S' modifiers
  98 bool OnlyUpdate = false;         ///< 'u' modifier
  99 bool Verbose = false;            ///< 'v' modifier
 100 bool ReallyVerbose = false;      ///< 'V' modifier
 101 bool Compression = false;        ///< 'z' modifier
 102
 103 // Relative Positional Argument (for insert/move). This variable holds
 104 // the name of the archive member to which the 'a', 'b' or 'i' modifier
 105 // refers. Only one of 'a', 'b' or 'i' can be specified so we only need
 106 // one variable.
 107 std::string RelPos;
 108
 109 // Select which of multiple entries in the archive with the same name should be
 110 // used (specified with -N) for the delete and extract operations.
 111 int Count = 1;
 112
 113 // This variable holds the name of the archive file as given on the
 114 // command line.
 115 std::string ArchiveName;
 116
 117 // This variable holds the list of member files to proecess, as given
 118 // on the command line.
 119 std::vector<std::string> Members;
 120
 121 // This variable holds the (possibly expanded) list of path objects that
 122 // correspond to files we will
 123 std::set<sys::Path> Paths;
 124
 125 // The Archive object to which all the editing operations will be sent.
 126 Archive* TheArchive = 0;
 127
 128 // getRelPos - Extract the member filename from the command line for
 129 // the [relpos] argument associated with a, b, and i modifiers
 130 void getRelPos() {
 131   if(RestOfArgs.size() > 0) {
 132     RelPos = RestOfArgs[0];
 133     RestOfArgs.erase(RestOfArgs.begin());
 134   }
 135   else
 136     throw "Expected [relpos] for a, b, or i modifier";
 137 }
 138
 139 // getCount - Extract the [count] argument associated with the N modifier
 140 // from the command line and check its value.
 141 void getCount() {
 142   if(RestOfArgs.size() > 0) {
 143     Count = atoi(RestOfArgs[0].c_str());
 144     RestOfArgs.erase(RestOfArgs.begin());
 145   }
 146   else
 147     throw "Expected [count] value with N modifier";
 148
 149   // Non-positive counts are not allowed
 150   if (Count < 1)
 151     throw "Invalid [count] value (not a positive integer)";
 152 }
 153
 154 // getArchive - Get the archive file name from the command line
 155 void getArchive() {
 156   if(RestOfArgs.size() > 0) {
 157     ArchiveName = RestOfArgs[0];
 158     RestOfArgs.erase(RestOfArgs.begin());
 159   }
 160   else
 161     throw "An archive name must be specified.";
 162 }
 163
 164 // getMembers - Copy over remaining items in RestOfArgs to our Members vector
 165 // This is just for clarity.
 166 void getMembers() {
 167   if(RestOfArgs.size() > 0)
 168     Members = std::vector<std::string>(RestOfArgs);
 169 }
 170
 171 // parseCommandLine - Parse the command line options as presented and return the
 172 // operation specified. Process all modifiers and check to make sure that
 173 // constraints on modifier/operation pairs have not been violated.
 174 ArchiveOperation parseCommandLine() {
 175
 176   // Keep track of number of operations. We can only specify one
 177   // per execution.
 178   unsigned NumOperations = 0;
 179
 180   // Keep track of the number of positional modifiers (a,b,i). Only
 181   // one can be specified.
 182   unsigned NumPositional = 0;
 183
 184   // Keep track of which operation was requested
 185   ArchiveOperation Operation = NoOperation;
 186
 187   for(unsigned i=0; i<Options.size(); ++i) {
 188     switch(Options[i]) {
 189     case 'd': ++NumOperations; Operation = Delete; break;
 190     case 'm': ++NumOperations; Operation = Move ; break;
 191     case 'p': ++NumOperations; Operation = Print; break;
 192     case 'q': ++NumOperations; Operation = QuickAppend; break;
 193     case 'r': ++NumOperations; Operation = ReplaceOrInsert; break;
 194     case 't': ++NumOperations; Operation = DisplayTable; break;
 195     case 'x': ++NumOperations; Operation = Extract; break;
 196     case 'c': Create = true; break;
 197     case 'f': TruncateNames = true; break;
 198     case 'k': DontSkipBitcode = true; break;
 199     case 'l': /* accepted but unused */ break;
 200     case 'o': OriginalDates = true; break;
 201     case 'P': FullPath = true; break;
 202     case 'R': RecurseDirectories = true; break;
 203     case 's': SymTable = true; break;
 204     case 'S': SymTable = false; break;
 205     case 'u': OnlyUpdate = true; break;
 206     case 'v': Verbose = true; break;
 207     case 'V': Verbose = ReallyVerbose = true; break;
 208     case 'z': Compression = true; break;
 209     case 'a':
 210       getRelPos();
 211       AddAfter = true;
 212       NumPositional++;
 213       break;
 214     case 'b':
 215       getRelPos();
 216       AddBefore = true;
 217       NumPositional++;
 218       break;
 219     case 'i':
 220       getRelPos();
 221       InsertBefore = true;
 222       NumPositional++;
 223       break;
 224     case 'N':
 225       getCount();
 226       UseCount = true;
 227       break;
 228     default:
 229       cl::PrintHelpMessage();
 230     }
 231   }
 232
 233   // At this point, the next thing on the command line must be
 234   // the archive name.
 235   getArchive();
 236
 237   // Everything on the command line at this point is a member.
 238   getMembers();
 239
 240   // Perform various checks on the operation/modifier specification
 241   // to make sure we are dealing with a legal request.
 242   if (NumOperations == 0)
 243     throw "You must specify at least one of the operations";
 244   if (NumOperations > 1)
 245     throw "Only one operation may be specified";
 246   if (NumPositional > 1)
 247     throw "You may only specify one of a, b, and i modifiers";
 248   if (AddAfter || AddBefore || InsertBefore)
 249     if (Operation != Move && Operation != ReplaceOrInsert)
 250       throw "The 'a', 'b' and 'i' modifiers can only be specified with "
 251             "the 'm' or 'r' operations";
 252   if (RecurseDirectories && Operation != ReplaceOrInsert)
 253     throw "The 'R' modifiers is only applicabe to the 'r' operation";
 254   if (OriginalDates && Operation != Extract)
 255     throw "The 'o' modifier is only applicable to the 'x' operation";
 256   if (TruncateNames && Operation!=QuickAppend && Operation!=ReplaceOrInsert)
 257     throw "The 'f' modifier is only applicable to the 'q' and 'r' operations";
 258   if (OnlyUpdate && Operation != ReplaceOrInsert)
 259     throw "The 'u' modifier is only applicable to the 'r' operation";
 260   if (Compression && Operation!=ReplaceOrInsert && Operation!=Extract)
 261     throw "The 'z' modifier is only applicable to the 'r' and 'x' operations";
 262   if (Count > 1 && Members.size() > 1)
 263     throw "Only one member name may be specified with the 'N' modifier";
 264
 265   // Return the parsed operation to the caller
 266   return Operation;
 267 }
 268
 269 // recurseDirectories - Implements the "R" modifier. This function scans through
 270 // the Paths vector (built by buildPaths, below) and replaces any directories it
 271 // finds with all the files in that directory (recursively). It uses the
 272 // sys::Path::getDirectoryContent method to perform the actual directory scans.
 273 bool
 274 recurseDirectories(const sys::Path& path,
 275                    std::set<sys::Path>& result, std::string* ErrMsg) {
 276   result.clear();
 277   if (RecurseDirectories) {
 278     std::set<sys::Path> content;
 279     if (path.getDirectoryContents(content, ErrMsg))
 280       return true;
 281
 282     for (std::set<sys::Path>::iterator I = content.begin(), E = content.end();
 283          I != E; ++I) {
 284       // Make sure it exists and is a directory
 285       sys::PathWithStatus PwS(*I);
 286       const sys::FileStatus *Status = PwS.getFileStatus(false, ErrMsg);
 287       if (!Status)
 288         return true;
 289       if (Status->isDir) {
 290         std::set<sys::Path> moreResults;
 291         if (recurseDirectories(*I, moreResults, ErrMsg))
 292           return true;
 293         result.insert(moreResults.begin(), moreResults.end());
 294       } else {
 295           result.insert(*I);
 296       }
 297     }
 298   }
 299   return false;
 300 }
 301
 302 // buildPaths - Convert the strings in the Members vector to sys::Path objects
 303 // and make sure they are valid and exist exist. This check is only needed for
 304 // the operations that add/replace files to the archive ('q' and 'r')
 305 bool buildPaths(bool checkExistence, std::string* ErrMsg) {
 306   for (unsigned i = 0; i < Members.size(); i++) {
 307     sys::Path aPath;
 308     if (!aPath.set(Members[i]))
 309       throw std::string("File member name invalid: ") + Members[i];
 310     if (checkExistence) {
 311       if (!aPath.exists())
 312         throw std::string("File does not exist: ") + Members[i];
 313       std::string Err;
 314       sys::PathWithStatus PwS(aPath);
 315       const sys::FileStatus *si = PwS.getFileStatus(false, &Err);
 316       if (!si)
 317         throw Err;
 318       if (si->isDir) {
 319         std::set<sys::Path> dirpaths;
 320         if (recurseDirectories(aPath, dirpaths, ErrMsg))
 321           return true;
 322         Paths.insert(dirpaths.begin(),dirpaths.end());
 323       } else {
 324         Paths.insert(aPath);
 325       }
 326     } else {
 327       Paths.insert(aPath);
 328     }
 329   }
 330   return false;
 331 }
 332
 333 // printSymbolTable - print out the archive's symbol table.
 334 void printSymbolTable() {
 335   std::cout << "\nArchive Symbol Table:\n";
 336   const Archive::SymTabType& symtab = TheArchive->getSymbolTable();
 337   for (Archive::SymTabType::const_iterator I=symtab.begin(), E=symtab.end();
 338        I != E; ++I ) {
 339     unsigned offset = TheArchive->getFirstFileOffset() + I->second;
 340     std::cout << " " << std::setw(9) << offset << "\t" << I->first <<"\n";
 341   }
 342 }
 343
 344 // doPrint - Implements the 'p' operation. This function traverses the archive
 345 // looking for members that match the path list. It is careful to uncompress
 346 // things that should be and to skip bitcode files unless the 'k' modifier was
 347 // given.
 348 bool doPrint(std::string* ErrMsg) {
 349   if (buildPaths(false, ErrMsg))
 350     return true;
 351   unsigned countDown = Count;
 352   for (Archive::iterator I = TheArchive->begin(), E = TheArchive->end();
 353        I != E; ++I ) {
 354     if (Paths.empty() ||
 355         (std::find(Paths.begin(), Paths.end(), I->getPath()) != Paths.end())) {
 356       if (countDown == 1) {
 357         const char* data = reinterpret_cast<const char*>(I->getData());
 358
 359         // Skip things that don't make sense to print
 360         if (I->isLLVMSymbolTable() || I->isSVR4SymbolTable() ||
 361             I->isBSD4SymbolTable() || (!DontSkipBitcode && I->isBitcode()))
 362           continue;
 363
 364         if (Verbose)
 365           std::cout << "Printing " << I->getPath().toString() << "\n";
 366
 367         unsigned len = I->getSize();
 368         std::cout.write(data, len);
 369       } else {
 370         countDown--;
 371       }
 372     }
 373   }
 374   return false;
 375 }
 376
 377 // putMode - utility function for printing out the file mode when the 't'
 378 // operation is in verbose mode.
 379 void
 380 printMode(unsigned mode) {
 381   if (mode & 004)
 382     std::cout << "r";
 383   else
 384     std::cout << "-";
 385   if (mode & 002)
 386     std::cout << "w";
 387   else
 388     std::cout << "-";
 389   if (mode & 001)
 390     std::cout << "x";
 391   else
 392     std::cout << "-";
 393 }
 394
 395 // doDisplayTable - Implement the 't' operation. This function prints out just
 396 // the file names of each of the members. However, if verbose mode is requested
 397 // ('v' modifier) then the file type, permission mode, user, group, size, and
 398 // modification time are also printed.
 399 bool
 400 doDisplayTable(std::string* ErrMsg) {
 401   if (buildPaths(false, ErrMsg))
 402     return true;
 403   for (Archive::iterator I = TheArchive->begin(), E = TheArchive->end();
 404        I != E; ++I ) {
 405     if (Paths.empty() ||
 406         (std::find(Paths.begin(), Paths.end(), I->getPath()) != Paths.end())) {
 407       if (Verbose) {
 408         // FIXME: Output should be this format:
 409         // Zrw-r--r--  500/ 500    525 Nov  8 17:42 2004 Makefile
 410         if (I->isBitcode())
 411           std::cout << "b";
 412         else if (I->isCompressed())
 413           std::cout << "Z";
 414         else
 415           std::cout << " ";
 416         unsigned mode = I->getMode();
 417         printMode((mode >> 6) & 007);
 418         printMode((mode >> 3) & 007);
 419         printMode(mode & 007);
 420         std::cout << " " << std::setw(4) << I->getUser();
 421         std::cout << "/" << std::setw(4) << I->getGroup();
 422         std::cout << " " << std::setw(8) << I->getSize();
 423         std::cout << " " << std::setw(20) <<
 424           I->getModTime().toString().substr(4);
 425         std::cout << " " << I->getPath().toString() << "\n";
 426       } else {
 427         std::cout << I->getPath().toString() << "\n";
 428       }
 429     }
 430   }
 431   if (ReallyVerbose)
 432     printSymbolTable();
 433   return false;
 434 }
 435
 436 // doExtract - Implement the 'x' operation. This function extracts files back to
 437 // the file system, making sure to uncompress any that were compressed
 438 bool
 439 doExtract(std::string* ErrMsg) {
 440   if (buildPaths(false, ErrMsg))
 441     return true;
 442   for (Archive::iterator I = TheArchive->begin(), E = TheArchive->end();
 443        I != E; ++I ) {
 444     if (Paths.empty() ||
 445         (std::find(Paths.begin(), Paths.end(), I->getPath()) != Paths.end())) {
 446
 447       // Make sure the intervening directories are created
 448       if (I->hasPath()) {
 449         sys::Path dirs(I->getPath());
 450         dirs.eraseComponent();
 451         if (dirs.createDirectoryOnDisk(/*create_parents=*/true, ErrMsg))
 452           return true;
 453       }
 454
 455       // Open up a file stream for writing
 456       std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
 457                                    std::ios::binary;
 458       std::ofstream file(I->getPath().c_str(), io_mode);
 459
 460       // Get the data and its length
 461       const char* data = reinterpret_cast<const char*>(I->getData());
 462       unsigned len = I->getSize();
 463
 464       // Write the data.
 465       file.write(data,len);
 466       file.close();
 467
 468       // If we're supposed to retain the original modification times, etc. do so
 469       // now.
 470       if (OriginalDates)
 471         I->getPath().setStatusInfoOnDisk(I->getFileStatus());
 472     }
 473   }
 474   return false;
 475 }
 476
 477 // doDelete - Implement the delete operation. This function deletes zero or more
 478 // members from the archive. Note that if the count is specified, there should
 479 // be no more than one path in the Paths list or else this algorithm breaks.
 480 // That check is enforced in parseCommandLine (above).
 481 bool
 482 doDelete(std::string* ErrMsg) {
 483   if (buildPaths(false, ErrMsg))
 484     return true;
 485   if (Paths.empty())
 486     return false;
 487   unsigned countDown = Count;
 488   for (Archive::iterator I = TheArchive->begin(), E = TheArchive->end();
 489        I != E; ) {
 490     if (std::find(Paths.begin(), Paths.end(), I->getPath()) != Paths.end()) {
 491       if (countDown == 1) {
 492         Archive::iterator J = I;
 493         ++I;
 494         TheArchive->erase(J);
 495       } else
 496         countDown--;
 497     } else {
 498       ++I;
 499     }
 500   }
 501
 502   // We're done editting, reconstruct the archive.
 503   if (TheArchive->writeToDisk(SymTable,TruncateNames,Compression,ErrMsg))
 504     return true;
 505   if (ReallyVerbose)
 506     printSymbolTable();
 507   return false;
 508 }
 509
 510 // doMore - Implement the move operation. This function re-arranges just the
 511 // order of the archive members so that when the archive is written the move
 512 // of the members is accomplished. Note the use of the RelPos variable to
 513 // determine where the items should be moved to.
 514 bool
 515 doMove(std::string* ErrMsg) {
 516   if (buildPaths(false, ErrMsg))
 517     return true;
 518
 519   // By default and convention the place to move members to is the end of the
 520   // archive.
 521   Archive::iterator moveto_spot = TheArchive->end();
 522
 523   // However, if the relative positioning modifiers were used, we need to scan
 524   // the archive to find the member in question. If we don't find it, its no
 525   // crime, we just move to the end.
 526   if (AddBefore || InsertBefore || AddAfter) {
 527     for (Archive::iterator I = TheArchive->begin(), E= TheArchive->end();
 528          I != E; ++I ) {
 529       if (RelPos == I->getPath().toString()) {
 530         if (AddAfter) {
 531           moveto_spot = I;
 532           moveto_spot++;
 533         } else {
 534           moveto_spot = I;
 535         }
 536         break;
 537       }
 538     }
 539   }
 540
 541   // Keep a list of the paths remaining to be moved
 542   std::set<sys::Path> remaining(Paths);
 543
 544   // Scan the archive again, this time looking for the members to move to the
 545   // moveto_spot.
 546   for (Archive::iterator I = TheArchive->begin(), E= TheArchive->end();
 547        I != E && !remaining.empty(); ++I ) {
 548     std::set<sys::Path>::iterator found =
 549       std::find(remaining.begin(),remaining.end(),I->getPath());
 550     if (found != remaining.end()) {
 551       if (I != moveto_spot)
 552         TheArchive->splice(moveto_spot,*TheArchive,I);
 553       remaining.erase(found);
 554     }
 555   }
 556
 557   // We're done editting, reconstruct the archive.
 558   if (TheArchive->writeToDisk(SymTable,TruncateNames,Compression,ErrMsg))
 559     return true;
 560   if (ReallyVerbose)
 561     printSymbolTable();
 562   return false;
 563 }
 564
 565 // doQuickAppend - Implements the 'q' operation. This function just
 566 // indiscriminantly adds the members to the archive and rebuilds it.
 567 bool
 568 doQuickAppend(std::string* ErrMsg) {
 569   // Get the list of paths to append.
 570   if (buildPaths(true, ErrMsg))
 571     return true;
 572   if (Paths.empty())
 573     return false;
 574
 575   // Append them quickly.
 576   for (std::set<sys::Path>::iterator PI = Paths.begin(), PE = Paths.end();
 577        PI != PE; ++PI) {
 578     if (TheArchive->addFileBefore(*PI,TheArchive->end(),ErrMsg))
 579       return true;
 580   }
 581
 582   // We're done editting, reconstruct the archive.
 583   if (TheArchive->writeToDisk(SymTable,TruncateNames,Compression,ErrMsg))
 584     return true;
 585   if (ReallyVerbose)
 586     printSymbolTable();
 587   return false;
 588 }
 589
 590 // doReplaceOrInsert - Implements the 'r' operation. This function will replace
 591 // any existing files or insert new ones into the archive.
 592 bool
 593 doReplaceOrInsert(std::string* ErrMsg) {
 594
 595   // Build the list of files to be added/replaced.
 596   if (buildPaths(true, ErrMsg))
 597     return true;
 598   if (Paths.empty())
 599     return false;
 600
 601   // Keep track of the paths that remain to be inserted.
 602   std::set<sys::Path> remaining(Paths);
 603
 604   // Default the insertion spot to the end of the archive
 605   Archive::iterator insert_spot = TheArchive->end();
 606
 607   // Iterate over the archive contents
 608   for (Archive::iterator I = TheArchive->begin(), E = TheArchive->end();
 609        I != E && !remaining.empty(); ++I ) {
 610
 611     // Determine if this archive member matches one of the paths we're trying
 612     // to replace.
 613
 614     std::set<sys::Path>::iterator found = remaining.end();
 615     for (std::set<sys::Path>::iterator RI = remaining.begin(),
 616          RE = remaining.end(); RI != RE; ++RI ) {
 617       std::string compare(RI->toString());
 618       if (TruncateNames && compare.length() > 15) {
 619         const char* nm = compare.c_str();
 620         unsigned len = compare.length();
 621         size_t slashpos = compare.rfind('/');
 622         if (slashpos != std::string::npos) {
 623           nm += slashpos + 1;
 624           len -= slashpos +1;
 625         }
 626         if (len > 15)
 627           len = 15;
 628         compare.assign(nm,len);
 629       }
 630       if (compare == I->getPath().toString()) {
 631         found = RI;
 632         break;
 633       }
 634     }
 635
 636     if (found != remaining.end()) {
 637       std::string Err;
 638       sys::PathWithStatus PwS(*found);
 639       const sys::FileStatus *si = PwS.getFileStatus(false, &Err);
 640       if (!si)
 641         return true;
 642       if (!si->isDir) {
 643         if (OnlyUpdate) {
 644           // Replace the item only if it is newer.
 645           if (si->modTime > I->getModTime())
 646             if (I->replaceWith(*found, ErrMsg))
 647               return true;
 648         } else {
 649           // Replace the item regardless of time stamp
 650           if (I->replaceWith(*found, ErrMsg))
 651             return true;
 652         }
 653       } else {
 654         // We purposefully ignore directories.
 655       }
 656
 657       // Remove it from our "to do" list
 658       remaining.erase(found);
 659     }
 660
 661     // Determine if this is the place where we should insert
 662     if ((AddBefore || InsertBefore) && (RelPos == I->getPath().toString()))
 663       insert_spot = I;
 664     else if (AddAfter && (RelPos == I->getPath().toString())) {
 665       insert_spot = I;
 666       insert_spot++;
 667     }
 668   }
 669
 670   // If we didn't replace all the members, some will remain and need to be
 671   // inserted at the previously computed insert-spot.
 672   if (!remaining.empty()) {
 673     for (std::set<sys::Path>::iterator PI = remaining.begin(),
 674          PE = remaining.end(); PI != PE; ++PI) {
 675       if (TheArchive->addFileBefore(*PI,insert_spot, ErrMsg))
 676         return true;
 677     }
 678   }
 679
 680   // We're done editting, reconstruct the archive.
 681   if (TheArchive->writeToDisk(SymTable,TruncateNames,Compression,ErrMsg))
 682     return true;
 683   if (ReallyVerbose)
 684     printSymbolTable();
 685   return false;
 686 }
 687
 688 // main - main program for llvm-ar .. see comments in the code
 689 int main(int argc, char **argv) {
 690   // Print a stack trace if we signal out.
 691   sys::PrintStackTraceOnErrorSignal();
 692   PrettyStackTraceProgram X(argc, argv);
 693   llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
 694
 695   // Have the command line options parsed and handle things
 696   // like --help and --version.
 697   cl::ParseCommandLineOptions(argc, argv,
 698     "LLVM Archiver (llvm-ar)\n\n"
 699     "  This program archives bitcode files into single libraries\n"
 700   );
 701
 702   int exitCode = 0;
 703
 704   // Make sure we don't exit with "unhandled exception".
 705   try {
 706     // Do our own parsing of the command line because the CommandLine utility
 707     // can't handle the grouped positional parameters without a dash.
 708     ArchiveOperation Operation = parseCommandLine();
 709
 710     // Check the path name of the archive
 711     sys::Path ArchivePath;
 712     if (!ArchivePath.set(ArchiveName))
 713       throw std::string("Archive name invalid: ") + ArchiveName;
 714
 715     // Create or open the archive object.
 716     if (!ArchivePath.exists()) {
 717       // Produce a warning if we should and we're creating the archive
 718       if (!Create)
 719         std::cerr << argv[0] << ": creating " << ArchivePath.toString() << "\n";
 720       TheArchive = Archive::CreateEmpty(ArchivePath);
 721       TheArchive->writeToDisk();
 722     } else {
 723       std::string Error;
 724       TheArchive = Archive::OpenAndLoad(ArchivePath, &Error);
 725       if (TheArchive == 0) {
 726         std::cerr << argv[0] << ": error loading '" << ArchivePath << "': "
 727                   << Error << "!\n";
 728         return 1;
 729       }
 730     }
 731
 732     // Make sure we're not fooling ourselves.
 733     assert(TheArchive && "Unable to instantiate the archive");
 734
 735     // Make sure we clean up the archive even on failure.
 736     std::auto_ptr<Archive> AutoArchive(TheArchive);
 737
 738     // Perform the operation
 739     std::string ErrMsg;
 740     bool haveError = false;
 741     switch (Operation) {
 742       case Print:           haveError = doPrint(&ErrMsg); break;
 743       case Delete:          haveError = doDelete(&ErrMsg); break;
 744       case Move:            haveError = doMove(&ErrMsg); break;
 745       case QuickAppend:     haveError = doQuickAppend(&ErrMsg); break;
 746       case ReplaceOrInsert: haveError = doReplaceOrInsert(&ErrMsg); break;
 747       case DisplayTable:    haveError = doDisplayTable(&ErrMsg); break;
 748       case Extract:         haveError = doExtract(&ErrMsg); break;
 749       case NoOperation:
 750         std::cerr << argv[0] << ": No operation was selected.\n";
 751         break;
 752     }
 753     if (haveError) {
 754       std::cerr << argv[0] << ": " << ErrMsg << "\n";
 755       return 1;
 756     }
 757   } catch (const char*msg) {
 758     // These errors are usage errors, thrown only by the various checks in the
 759     // code above.
 760     std::cerr << argv[0] << ": " << msg << "\n\n";
 761     cl::PrintHelpMessage();
 762     exitCode = 1;
 763   } catch (const std::string& msg) {
 764     // These errors are thrown by LLVM libraries (e.g. lib System) and represent
 765     // a more serious error so we bump the exitCode and don't print the usage.
 766     std::cerr << argv[0] << ": " << msg << "\n";
 767     exitCode = 2;
 768   } catch (...) {
 769     // This really shouldn't happen, but just in case ....
 770     std::cerr << argv[0] << ": An unexpected unknown exception occurred.\n";
 771     exitCode = 3;
 772   }
 773
 774   // Return result code back to operating system.
 775   return exitCode;
 776 }