lib/Support/CommandLine.cpp

   1 //===-- CommandLine.cpp - Command line parser implementation --------------===//
   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 // This class implements a command line argument processor that is useful when
  11 // creating a tool.  It provides a simple, minimalistic interface that is easily
  12 // extensible and supports nonlocal (library) command line options.
  13 //
  14 // Note that rather than trying to figure out what this code does, you could try
  15 // reading the library documentation located in docs/CommandLine.html
  16 //
  17 //===----------------------------------------------------------------------===//
  18
  19 #include "llvm/Support/CommandLine.h"
  20 #include "llvm/Support/Debug.h"
  21 #include "llvm/Support/ErrorHandling.h"
  22 #include "llvm/Support/MemoryBuffer.h"
  23 #include "llvm/Support/ManagedStatic.h"
  24 #include "llvm/Support/raw_ostream.h"
  25 #include "llvm/Target/TargetRegistry.h"
  26 #include "llvm/System/Host.h"
  27 #include "llvm/System/Path.h"
  28 #include "llvm/ADT/OwningPtr.h"
  29 #include "llvm/ADT/SmallPtrSet.h"
  30 #include "llvm/ADT/SmallString.h"
  31 #include "llvm/ADT/StringMap.h"
  32 #include "llvm/ADT/Twine.h"
  33 #include "llvm/Config/config.h"
  34 #include <cerrno>
  35 #include <cstdlib>
  36 using namespace llvm;
  37 using namespace cl;
  38
  39 //===----------------------------------------------------------------------===//
  40 // Template instantiations and anchors.
  41 //
  42 namespace llvm { namespace cl {
  43 TEMPLATE_INSTANTIATION(class basic_parser<bool>);
  44 TEMPLATE_INSTANTIATION(class basic_parser<boolOrDefault>);
  45 TEMPLATE_INSTANTIATION(class basic_parser<int>);
  46 TEMPLATE_INSTANTIATION(class basic_parser<unsigned>);
  47 TEMPLATE_INSTANTIATION(class basic_parser<double>);
  48 TEMPLATE_INSTANTIATION(class basic_parser<float>);
  49 TEMPLATE_INSTANTIATION(class basic_parser<std::string>);
  50 TEMPLATE_INSTANTIATION(class basic_parser<char>);
  51
  52 TEMPLATE_INSTANTIATION(class opt<unsigned>);
  53 TEMPLATE_INSTANTIATION(class opt<int>);
  54 TEMPLATE_INSTANTIATION(class opt<std::string>);
  55 TEMPLATE_INSTANTIATION(class opt<char>);
  56 TEMPLATE_INSTANTIATION(class opt<bool>);
  57 } } // end namespace llvm::cl
  58
  59 void Option::anchor() {}
  60 void basic_parser_impl::anchor() {}
  61 void parser<bool>::anchor() {}
  62 void parser<boolOrDefault>::anchor() {}
  63 void parser<int>::anchor() {}
  64 void parser<unsigned>::anchor() {}
  65 void parser<double>::anchor() {}
  66 void parser<float>::anchor() {}
  67 void parser<std::string>::anchor() {}
  68 void parser<char>::anchor() {}
  69
  70 //===----------------------------------------------------------------------===//
  71
  72 // Globals for name and overview of program.  Program name is not a string to
  73 // avoid static ctor/dtor issues.
  74 static char ProgramName[80] = "<premain>";
  75 static const char *ProgramOverview = 0;
  76
  77 // This collects additional help to be printed.
  78 static ManagedStatic<std::vector<const char*> > MoreHelp;
  79
  80 extrahelp::extrahelp(const char *Help)
  81   : morehelp(Help) {
  82   MoreHelp->push_back(Help);
  83 }
  84
  85 static bool OptionListChanged = false;
  86
  87 // MarkOptionsChanged - Internal helper function.
  88 void cl::MarkOptionsChanged() {
  89   OptionListChanged = true;
  90 }
  91
  92 /// RegisteredOptionList - This is the list of the command line options that
  93 /// have statically constructed themselves.
  94 static Option *RegisteredOptionList = 0;
  95
  96 void Option::addArgument() {
  97   assert(NextRegistered == 0 && "argument multiply registered!");
  98
  99   NextRegistered = RegisteredOptionList;
 100   RegisteredOptionList = this;
 101   MarkOptionsChanged();
 102 }
 103
 104
 105 //===----------------------------------------------------------------------===//
 106 // Basic, shared command line option processing machinery.
 107 //
 108
 109 /// GetOptionInfo - Scan the list of registered options, turning them into data
 110 /// structures that are easier to handle.
 111 static void GetOptionInfo(SmallVectorImpl<Option*> &PositionalOpts,
 112                           SmallVectorImpl<Option*> &SinkOpts,
 113                           StringMap<Option*> &OptionsMap) {
 114   SmallVector<const char*, 16> OptionNames;
 115   Option *CAOpt = 0;  // The ConsumeAfter option if it exists.
 116   for (Option *O = RegisteredOptionList; O; O = O->getNextRegisteredOption()) {
 117     // If this option wants to handle multiple option names, get the full set.
 118     // This handles enum options like "-O1 -O2" etc.
 119     O->getExtraOptionNames(OptionNames);
 120     if (O->ArgStr[0])
 121       OptionNames.push_back(O->ArgStr);
 122
 123     // Handle named options.
 124     for (size_t i = 0, e = OptionNames.size(); i != e; ++i) {
 125       // Add argument to the argument map!
 126       if (OptionsMap.GetOrCreateValue(OptionNames[i], O).second != O) {
 127         errs() << ProgramName << ": CommandLine Error: Argument '"
 128              << OptionNames[i] << "' defined more than once!\n";
 129       }
 130     }
 131
 132     OptionNames.clear();
 133
 134     // Remember information about positional options.
 135     if (O->getFormattingFlag() == cl::Positional)
 136       PositionalOpts.push_back(O);
 137     else if (O->getMiscFlags() & cl::Sink) // Remember sink options
 138       SinkOpts.push_back(O);
 139     else if (O->getNumOccurrencesFlag() == cl::ConsumeAfter) {
 140       if (CAOpt)
 141         O->error("Cannot specify more than one option with cl::ConsumeAfter!");
 142       CAOpt = O;
 143     }
 144   }
 145
 146   if (CAOpt)
 147     PositionalOpts.push_back(CAOpt);
 148
 149   // Make sure that they are in order of registration not backwards.
 150   std::reverse(PositionalOpts.begin(), PositionalOpts.end());
 151 }
 152
 153
 154 /// LookupOption - Lookup the option specified by the specified option on the
 155 /// command line.  If there is a value specified (after an equal sign) return
 156 /// that as well.  This assumes that leading dashes have already been stripped.
 157 static Option *LookupOption(StringRef &Arg, StringRef &Value,
 158                             const StringMap<Option*> &OptionsMap) {
 159   // Reject all dashes.
 160   if (Arg.empty()) return 0;
 161
 162   size_t EqualPos = Arg.find('=');
 163
 164   // If we have an equals sign, remember the value.
 165   if (EqualPos == StringRef::npos) {
 166     // Look up the option.
 167     StringMap<Option*>::const_iterator I = OptionsMap.find(Arg);
 168     return I != OptionsMap.end() ? I->second : 0;
 169   }
 170
 171   // If the argument before the = is a valid option name, we match.  If not,
 172   // return Arg unmolested.
 173   StringMap<Option*>::const_iterator I =
 174     OptionsMap.find(Arg.substr(0, EqualPos));
 175   if (I == OptionsMap.end()) return 0;
 176
 177   Value = Arg.substr(EqualPos+1);
 178   Arg = Arg.substr(0, EqualPos);
 179   return I->second;
 180 }
 181
 182 /// CommaSeparateAndAddOccurence - A wrapper around Handler->addOccurence() that
 183 /// does special handling of cl::CommaSeparated options.
 184 static bool CommaSeparateAndAddOccurence(Option *Handler, unsigned pos,
 185                                          StringRef ArgName,
 186                                          StringRef Value, bool MultiArg = false)
 187 {
 188   // Check to see if this option accepts a comma separated list of values.  If
 189   // it does, we have to split up the value into multiple values.
 190   if (Handler->getMiscFlags() & CommaSeparated) {
 191     StringRef Val(Value);
 192     StringRef::size_type Pos = Val.find(',');
 193
 194     while (Pos != StringRef::npos) {
 195       // Process the portion before the comma.
 196       if (Handler->addOccurrence(pos, ArgName, Val.substr(0, Pos), MultiArg))
 197         return true;
 198       // Erase the portion before the comma, AND the comma.
 199       Val = Val.substr(Pos+1);
 200       Value.substr(Pos+1);  // Increment the original value pointer as well.
 201       // Check for another comma.
 202       Pos = Val.find(',');
 203     }
 204
 205     Value = Val;
 206   }
 207
 208   if (Handler->addOccurrence(pos, ArgName, Value, MultiArg))
 209     return true;
 210
 211   return false;
 212 }
 213
 214 /// ProvideOption - For Value, this differentiates between an empty value ("")
 215 /// and a null value (StringRef()).  The later is accepted for arguments that
 216 /// don't allow a value (-foo) the former is rejected (-foo=).
 217 static inline bool ProvideOption(Option *Handler, StringRef ArgName,
 218                                  StringRef Value, int argc, char **argv,
 219                                  int &i) {
 220   // Is this a multi-argument option?
 221   unsigned NumAdditionalVals = Handler->getNumAdditionalVals();
 222
 223   // Enforce value requirements
 224   switch (Handler->getValueExpectedFlag()) {
 225   case ValueRequired:
 226     if (Value.data() == 0) {       // No value specified?
 227       if (i+1 >= argc)
 228         return Handler->error("requires a value!");
 229       // Steal the next argument, like for '-o filename'
 230       Value = argv[++i];
 231     }
 232     break;
 233   case ValueDisallowed:
 234     if (NumAdditionalVals > 0)
 235       return Handler->error("multi-valued option specified"
 236                             " with ValueDisallowed modifier!");
 237
 238     if (Value.data())
 239       return Handler->error("does not allow a value! '" +
 240                             Twine(Value) + "' specified.");
 241     break;
 242   case ValueOptional:
 243     break;
 244
 245   default:
 246     errs() << ProgramName
 247          << ": Bad ValueMask flag! CommandLine usage error:"
 248          << Handler->getValueExpectedFlag() << "\n";
 249     llvm_unreachable(0);
 250   }
 251
 252   // If this isn't a multi-arg option, just run the handler.
 253   if (NumAdditionalVals == 0)
 254     return CommaSeparateAndAddOccurence(Handler, i, ArgName, Value);
 255
 256   // If it is, run the handle several times.
 257   bool MultiArg = false;
 258
 259   if (Value.data()) {
 260     if (CommaSeparateAndAddOccurence(Handler, i, ArgName, Value, MultiArg))
 261       return true;
 262     --NumAdditionalVals;
 263     MultiArg = true;
 264   }
 265
 266   while (NumAdditionalVals > 0) {
 267     if (i+1 >= argc)
 268       return Handler->error("not enough values!");
 269     Value = argv[++i];
 270
 271     if (CommaSeparateAndAddOccurence(Handler, i, ArgName, Value, MultiArg))
 272       return true;
 273     MultiArg = true;
 274     --NumAdditionalVals;
 275   }
 276   return false;
 277 }
 278
 279 static bool ProvidePositionalOption(Option *Handler, StringRef Arg, int i) {
 280   int Dummy = i;
 281   return ProvideOption(Handler, Handler->ArgStr, Arg, 0, 0, Dummy);
 282 }
 283
 284
 285 // Option predicates...
 286 static inline bool isGrouping(const Option *O) {
 287   return O->getFormattingFlag() == cl::Grouping;
 288 }
 289 static inline bool isPrefixedOrGrouping(const Option *O) {
 290   return isGrouping(O) || O->getFormattingFlag() == cl::Prefix;
 291 }
 292
 293 // getOptionPred - Check to see if there are any options that satisfy the
 294 // specified predicate with names that are the prefixes in Name.  This is
 295 // checked by progressively stripping characters off of the name, checking to
 296 // see if there options that satisfy the predicate.  If we find one, return it,
 297 // otherwise return null.
 298 //
 299 static Option *getOptionPred(StringRef Name, size_t &Length,
 300                              bool (*Pred)(const Option*),
 301                              const StringMap<Option*> &OptionsMap) {
 302
 303   StringMap<Option*>::const_iterator OMI = OptionsMap.find(Name);
 304
 305   // Loop while we haven't found an option and Name still has at least two
 306   // characters in it (so that the next iteration will not be the empty
 307   // string.
 308   while (OMI == OptionsMap.end() && Name.size() > 1) {
 309     Name = Name.substr(0, Name.size()-1);   // Chop off the last character.
 310     OMI = OptionsMap.find(Name);
 311   }
 312
 313   if (OMI != OptionsMap.end() && Pred(OMI->second)) {
 314     Length = Name.size();
 315     return OMI->second;    // Found one!
 316   }
 317   return 0;                // No option found!
 318 }
 319
 320 /// HandlePrefixedOrGroupedOption - The specified argument string (which started
 321 /// with at least one '-') does not fully match an available option.  Check to
 322 /// see if this is a prefix or grouped option.  If so, split arg into output an
 323 /// Arg/Value pair and return the Option to parse it with.
 324 static Option *HandlePrefixedOrGroupedOption(StringRef &Arg, StringRef &Value,
 325                                              bool &ErrorParsing,
 326                                          const StringMap<Option*> &OptionsMap) {
 327   if (Arg.size() == 1) return 0;
 328
 329   // Do the lookup!
 330   size_t Length = 0;
 331   Option *PGOpt = getOptionPred(Arg, Length, isPrefixedOrGrouping, OptionsMap);
 332   if (PGOpt == 0) return 0;
 333
 334   // If the option is a prefixed option, then the value is simply the
 335   // rest of the name...  so fall through to later processing, by
 336   // setting up the argument name flags and value fields.
 337   if (PGOpt->getFormattingFlag() == cl::Prefix) {
 338     Value = Arg.substr(Length);
 339     Arg = Arg.substr(0, Length);
 340     assert(OptionsMap.count(Arg) && OptionsMap.find(Arg)->second == PGOpt);
 341     return PGOpt;
 342   }
 343
 344   // This must be a grouped option... handle them now.  Grouping options can't
 345   // have values.
 346   assert(isGrouping(PGOpt) && "Broken getOptionPred!");
 347
 348   do {
 349     // Move current arg name out of Arg into OneArgName.
 350     StringRef OneArgName = Arg.substr(0, Length);
 351     Arg = Arg.substr(Length);
 352
 353     // Because ValueRequired is an invalid flag for grouped arguments,
 354     // we don't need to pass argc/argv in.
 355     assert(PGOpt->getValueExpectedFlag() != cl::ValueRequired &&
 356            "Option can not be cl::Grouping AND cl::ValueRequired!");
 357     int Dummy = 0;
 358     ErrorParsing |= ProvideOption(PGOpt, OneArgName,
 359                                   StringRef(), 0, 0, Dummy);
 360
 361     // Get the next grouping option.
 362     PGOpt = getOptionPred(Arg, Length, isGrouping, OptionsMap);
 363   } while (PGOpt && Length != Arg.size());
 364
 365   // Return the last option with Arg cut down to just the last one.
 366   return PGOpt;
 367 }
 368
 369
 370
 371 static bool RequiresValue(const Option *O) {
 372   return O->getNumOccurrencesFlag() == cl::Required ||
 373          O->getNumOccurrencesFlag() == cl::OneOrMore;
 374 }
 375
 376 static bool EatsUnboundedNumberOfValues(const Option *O) {
 377   return O->getNumOccurrencesFlag() == cl::ZeroOrMore ||
 378          O->getNumOccurrencesFlag() == cl::OneOrMore;
 379 }
 380
 381 /// ParseCStringVector - Break INPUT up wherever one or more
 382 /// whitespace characters are found, and store the resulting tokens in
 383 /// OUTPUT. The tokens stored in OUTPUT are dynamically allocated
 384 /// using strdup(), so it is the caller's responsibility to free()
 385 /// them later.
 386 ///
 387 static void ParseCStringVector(std::vector<char *> &OutputVector,
 388                                const char *Input) {
 389   // Characters which will be treated as token separators:
 390   StringRef Delims = " \v\f\t\r\n";
 391
 392   StringRef WorkStr(Input);
 393   while (!WorkStr.empty()) {
 394     // If the first character is a delimiter, strip them off.
 395     if (Delims.find(WorkStr[0]) != StringRef::npos) {
 396       size_t Pos = WorkStr.find_first_not_of(Delims);
 397       if (Pos == StringRef::npos) Pos = WorkStr.size();
 398       WorkStr = WorkStr.substr(Pos);
 399       continue;
 400     }
 401
 402     // Find position of first delimiter.
 403     size_t Pos = WorkStr.find_first_of(Delims);
 404     if (Pos == StringRef::npos) Pos = WorkStr.size();
 405
 406     // Everything from 0 to Pos is the next word to copy.
 407     char *NewStr = (char*)malloc(Pos+1);
 408     memcpy(NewStr, WorkStr.data(), Pos);
 409     NewStr[Pos] = 0;
 410     OutputVector.push_back(NewStr);
 411
 412     WorkStr = WorkStr.substr(Pos);
 413   }
 414 }
 415
 416 /// ParseEnvironmentOptions - An alternative entry point to the
 417 /// CommandLine library, which allows you to read the program's name
 418 /// from the caller (as PROGNAME) and its command-line arguments from
 419 /// an environment variable (whose name is given in ENVVAR).
 420 ///
 421 void cl::ParseEnvironmentOptions(const char *progName, const char *envVar,
 422                                  const char *Overview, bool ReadResponseFiles) {
 423   // Check args.
 424   assert(progName && "Program name not specified");
 425   assert(envVar && "Environment variable name missing");
 426
 427   // Get the environment variable they want us to parse options out of.
 428   const char *envValue = getenv(envVar);
 429   if (!envValue)
 430     return;
 431
 432   // Get program's "name", which we wouldn't know without the caller
 433   // telling us.
 434   std::vector<char*> newArgv;
 435   newArgv.push_back(strdup(progName));
 436
 437   // Parse the value of the environment variable into a "command line"
 438   // and hand it off to ParseCommandLineOptions().
 439   ParseCStringVector(newArgv, envValue);
 440   int newArgc = static_cast<int>(newArgv.size());
 441   ParseCommandLineOptions(newArgc, &newArgv[0], Overview, ReadResponseFiles);
 442
 443   // Free all the strdup()ed strings.
 444   for (std::vector<char*>::iterator i = newArgv.begin(), e = newArgv.end();
 445        i != e; ++i)
 446     free(*i);
 447 }
 448
 449
 450 /// ExpandResponseFiles - Copy the contents of argv into newArgv,
 451 /// substituting the contents of the response files for the arguments
 452 /// of type @file.
 453 static void ExpandResponseFiles(unsigned argc, char** argv,
 454                                 std::vector<char*>& newArgv) {
 455   for (unsigned i = 1; i != argc; ++i) {
 456     char *arg = argv[i];
 457
 458     if (arg[0] == '@') {
 459       sys::PathWithStatus respFile(++arg);
 460
 461       // Check that the response file is not empty (mmap'ing empty
 462       // files can be problematic).
 463       const sys::FileStatus *FileStat = respFile.getFileStatus();
 464       if (FileStat && FileStat->getSize() != 0) {
 465
 466         // Mmap the response file into memory.
 467         OwningPtr<MemoryBuffer>
 468           respFilePtr(MemoryBuffer::getFile(respFile.c_str()));
 469
 470         // If we could open the file, parse its contents, otherwise
 471         // pass the @file option verbatim.
 472
 473         // TODO: we should also support recursive loading of response files,
 474         // since this is how gcc behaves. (From their man page: "The file may
 475         // itself contain additional @file options; any such options will be
 476         // processed recursively.")
 477
 478         if (respFilePtr != 0) {
 479           ParseCStringVector(newArgv, respFilePtr->getBufferStart());
 480           continue;
 481         }
 482       }
 483     }
 484     newArgv.push_back(strdup(arg));
 485   }
 486 }
 487
 488 void cl::ParseCommandLineOptions(int argc, char **argv,
 489                                  const char *Overview, bool ReadResponseFiles) {
 490   // Process all registered options.
 491   SmallVector<Option*, 4> PositionalOpts;
 492   SmallVector<Option*, 4> SinkOpts;
 493   StringMap<Option*> Opts;
 494   GetOptionInfo(PositionalOpts, SinkOpts, Opts);
 495
 496   assert((!Opts.empty() || !PositionalOpts.empty()) &&
 497          "No options specified!");
 498
 499   // Expand response files.
 500   std::vector<char*> newArgv;
 501   if (ReadResponseFiles) {
 502     newArgv.push_back(strdup(argv[0]));
 503     ExpandResponseFiles(argc, argv, newArgv);
 504     argv = &newArgv[0];
 505     argc = static_cast<int>(newArgv.size());
 506   }
 507
 508   // Copy the program name into ProgName, making sure not to overflow it.
 509   std::string ProgName = sys::Path(argv[0]).getLast();
 510   size_t Len = std::min(ProgName.size(), size_t(79));
 511   memcpy(ProgramName, ProgName.data(), Len);
 512   ProgramName[Len] = '\0';
 513
 514   ProgramOverview = Overview;
 515   bool ErrorParsing = false;
 516
 517   // Check out the positional arguments to collect information about them.
 518   unsigned NumPositionalRequired = 0;
 519
 520   // Determine whether or not there are an unlimited number of positionals
 521   bool HasUnlimitedPositionals = false;
 522
 523   Option *ConsumeAfterOpt = 0;
 524   if (!PositionalOpts.empty()) {
 525     if (PositionalOpts[0]->getNumOccurrencesFlag() == cl::ConsumeAfter) {
 526       assert(PositionalOpts.size() > 1 &&
 527              "Cannot specify cl::ConsumeAfter without a positional argument!");
 528       ConsumeAfterOpt = PositionalOpts[0];
 529     }
 530
 531     // Calculate how many positional values are _required_.
 532     bool UnboundedFound = false;
 533     for (size_t i = ConsumeAfterOpt != 0, e = PositionalOpts.size();
 534          i != e; ++i) {
 535       Option *Opt = PositionalOpts[i];
 536       if (RequiresValue(Opt))
 537         ++NumPositionalRequired;
 538       else if (ConsumeAfterOpt) {
 539         // ConsumeAfter cannot be combined with "optional" positional options
 540         // unless there is only one positional argument...
 541         if (PositionalOpts.size() > 2)
 542           ErrorParsing |=
 543             Opt->error("error - this positional option will never be matched, "
 544                        "because it does not Require a value, and a "
 545                        "cl::ConsumeAfter option is active!");
 546       } else if (UnboundedFound && !Opt->ArgStr[0]) {
 547         // This option does not "require" a value...  Make sure this option is
 548         // not specified after an option that eats all extra arguments, or this
 549         // one will never get any!
 550         //
 551         ErrorParsing |= Opt->error("error - option can never match, because "
 552                                    "another positional argument will match an "
 553                                    "unbounded number of values, and this option"
 554                                    " does not require a value!");
 555       }
 556       UnboundedFound |= EatsUnboundedNumberOfValues(Opt);
 557     }
 558     HasUnlimitedPositionals = UnboundedFound || ConsumeAfterOpt;
 559   }
 560
 561   // PositionalVals - A vector of "positional" arguments we accumulate into
 562   // the process at the end.
 563   //
 564   SmallVector<std::pair<StringRef,unsigned>, 4> PositionalVals;
 565
 566   // If the program has named positional arguments, and the name has been run
 567   // across, keep track of which positional argument was named.  Otherwise put
 568   // the positional args into the PositionalVals list...
 569   Option *ActivePositionalArg = 0;
 570
 571   // Loop over all of the arguments... processing them.
 572   bool DashDashFound = false;  // Have we read '--'?
 573   for (int i = 1; i < argc; ++i) {
 574     Option *Handler = 0;
 575     StringRef Value;
 576     StringRef ArgName = "";
 577
 578     // If the option list changed, this means that some command line
 579     // option has just been registered or deregistered.  This can occur in
 580     // response to things like -load, etc.  If this happens, rescan the options.
 581     if (OptionListChanged) {
 582       PositionalOpts.clear();
 583       SinkOpts.clear();
 584       Opts.clear();
 585       GetOptionInfo(PositionalOpts, SinkOpts, Opts);
 586       OptionListChanged = false;
 587     }
 588
 589     // Check to see if this is a positional argument.  This argument is
 590     // considered to be positional if it doesn't start with '-', if it is "-"
 591     // itself, or if we have seen "--" already.
 592     //
 593     if (argv[i][0] != '-' || argv[i][1] == 0 || DashDashFound) {
 594       // Positional argument!
 595       if (ActivePositionalArg) {
 596         ProvidePositionalOption(ActivePositionalArg, argv[i], i);
 597         continue;  // We are done!
 598       }
 599
 600       if (!PositionalOpts.empty()) {
 601         PositionalVals.push_back(std::make_pair(argv[i],i));
 602
 603         // All of the positional arguments have been fulfulled, give the rest to
 604         // the consume after option... if it's specified...
 605         //
 606         if (PositionalVals.size() >= NumPositionalRequired &&
 607             ConsumeAfterOpt != 0) {
 608           for (++i; i < argc; ++i)
 609             PositionalVals.push_back(std::make_pair(argv[i],i));
 610           break;   // Handle outside of the argument processing loop...
 611         }
 612
 613         // Delay processing positional arguments until the end...
 614         continue;
 615       }
 616     } else if (argv[i][0] == '-' && argv[i][1] == '-' && argv[i][2] == 0 &&
 617                !DashDashFound) {
 618       DashDashFound = true;  // This is the mythical "--"?
 619       continue;              // Don't try to process it as an argument itself.
 620     } else if (ActivePositionalArg &&
 621                (ActivePositionalArg->getMiscFlags() & PositionalEatsArgs)) {
 622       // If there is a positional argument eating options, check to see if this
 623       // option is another positional argument.  If so, treat it as an argument,
 624       // otherwise feed it to the eating positional.
 625       ArgName = argv[i]+1;
 626       // Eat leading dashes.
 627       while (!ArgName.empty() && ArgName[0] == '-')
 628         ArgName = ArgName.substr(1);
 629
 630       Handler = LookupOption(ArgName, Value, Opts);
 631       if (!Handler || Handler->getFormattingFlag() != cl::Positional) {
 632         ProvidePositionalOption(ActivePositionalArg, argv[i], i);
 633         continue;  // We are done!
 634       }
 635
 636     } else {     // We start with a '-', must be an argument.
 637       ArgName = argv[i]+1;
 638       // Eat leading dashes.
 639       while (!ArgName.empty() && ArgName[0] == '-')
 640         ArgName = ArgName.substr(1);
 641
 642       Handler = LookupOption(ArgName, Value, Opts);
 643
 644       // Check to see if this "option" is really a prefixed or grouped argument.
 645       if (Handler == 0)
 646         Handler = HandlePrefixedOrGroupedOption(ArgName, Value,
 647                                                 ErrorParsing, Opts);
 648     }
 649
 650     if (Handler == 0) {
 651       if (SinkOpts.empty()) {
 652         errs() << ProgramName << ": Unknown command line argument '"
 653              << argv[i] << "'.  Try: '" << argv[0] << " -help'\n";
 654         ErrorParsing = true;
 655       } else {
 656         for (SmallVectorImpl<Option*>::iterator I = SinkOpts.begin(),
 657                E = SinkOpts.end(); I != E ; ++I)
 658           (*I)->addOccurrence(i, "", argv[i]);
 659       }
 660       continue;
 661     }
 662
 663     // If this is a named positional argument, just remember that it is the
 664     // active one...
 665     if (Handler->getFormattingFlag() == cl::Positional)
 666       ActivePositionalArg = Handler;
 667     else
 668       ErrorParsing |= ProvideOption(Handler, ArgName, Value, argc, argv, i);
 669   }
 670
 671   // Check and handle positional arguments now...
 672   if (NumPositionalRequired > PositionalVals.size()) {
 673     errs() << ProgramName
 674          << ": Not enough positional command line arguments specified!\n"
 675          << "Must specify at least " << NumPositionalRequired
 676          << " positional arguments: See: " << argv[0] << " -help\n";
 677
 678     ErrorParsing = true;
 679   } else if (!HasUnlimitedPositionals &&
 680              PositionalVals.size() > PositionalOpts.size()) {
 681     errs() << ProgramName
 682          << ": Too many positional arguments specified!\n"
 683          << "Can specify at most " << PositionalOpts.size()
 684          << " positional arguments: See: " << argv[0] << " -help\n";
 685     ErrorParsing = true;
 686
 687   } else if (ConsumeAfterOpt == 0) {
 688     // Positional args have already been handled if ConsumeAfter is specified.
 689     unsigned ValNo = 0, NumVals = static_cast<unsigned>(PositionalVals.size());
 690     for (size_t i = 0, e = PositionalOpts.size(); i != e; ++i) {
 691       if (RequiresValue(PositionalOpts[i])) {
 692         ProvidePositionalOption(PositionalOpts[i], PositionalVals[ValNo].first,
 693                                 PositionalVals[ValNo].second);
 694         ValNo++;
 695         --NumPositionalRequired;  // We fulfilled our duty...
 696       }
 697
 698       // If we _can_ give this option more arguments, do so now, as long as we
 699       // do not give it values that others need.  'Done' controls whether the
 700       // option even _WANTS_ any more.
 701       //
 702       bool Done = PositionalOpts[i]->getNumOccurrencesFlag() == cl::Required;
 703       while (NumVals-ValNo > NumPositionalRequired && !Done) {
 704         switch (PositionalOpts[i]->getNumOccurrencesFlag()) {
 705         case cl::Optional:
 706           Done = true;          // Optional arguments want _at most_ one value
 707           // FALL THROUGH
 708         case cl::ZeroOrMore:    // Zero or more will take all they can get...
 709         case cl::OneOrMore:     // One or more will take all they can get...
 710           ProvidePositionalOption(PositionalOpts[i],
 711                                   PositionalVals[ValNo].first,
 712                                   PositionalVals[ValNo].second);
 713           ValNo++;
 714           break;
 715         default:
 716           llvm_unreachable("Internal error, unexpected NumOccurrences flag in "
 717                  "positional argument processing!");
 718         }
 719       }
 720     }
 721   } else {
 722     assert(ConsumeAfterOpt && NumPositionalRequired <= PositionalVals.size());
 723     unsigned ValNo = 0;
 724     for (size_t j = 1, e = PositionalOpts.size(); j != e; ++j)
 725       if (RequiresValue(PositionalOpts[j])) {
 726         ErrorParsing |= ProvidePositionalOption(PositionalOpts[j],
 727                                                 PositionalVals[ValNo].first,
 728                                                 PositionalVals[ValNo].second);
 729         ValNo++;
 730       }
 731
 732     // Handle the case where there is just one positional option, and it's
 733     // optional.  In this case, we want to give JUST THE FIRST option to the
 734     // positional option and keep the rest for the consume after.  The above
 735     // loop would have assigned no values to positional options in this case.
 736     //
 737     if (PositionalOpts.size() == 2 && ValNo == 0 && !PositionalVals.empty()) {
 738       ErrorParsing |= ProvidePositionalOption(PositionalOpts[1],
 739                                               PositionalVals[ValNo].first,
 740                                               PositionalVals[ValNo].second);
 741       ValNo++;
 742     }
 743
 744     // Handle over all of the rest of the arguments to the
 745     // cl::ConsumeAfter command line option...
 746     for (; ValNo != PositionalVals.size(); ++ValNo)
 747       ErrorParsing |= ProvidePositionalOption(ConsumeAfterOpt,
 748                                               PositionalVals[ValNo].first,
 749                                               PositionalVals[ValNo].second);
 750   }
 751
 752   // Loop over args and make sure all required args are specified!
 753   for (StringMap<Option*>::iterator I = Opts.begin(),
 754          E = Opts.end(); I != E; ++I) {
 755     switch (I->second->getNumOccurrencesFlag()) {
 756     case Required:
 757     case OneOrMore:
 758       if (I->second->getNumOccurrences() == 0) {
 759         I->second->error("must be specified at least once!");
 760         ErrorParsing = true;
 761       }
 762       // Fall through
 763     default:
 764       break;
 765     }
 766   }
 767
 768   // Free all of the memory allocated to the map.  Command line options may only
 769   // be processed once!
 770   Opts.clear();
 771   PositionalOpts.clear();
 772   MoreHelp->clear();
 773
 774   // Free the memory allocated by ExpandResponseFiles.
 775   if (ReadResponseFiles) {
 776     // Free all the strdup()ed strings.
 777     for (std::vector<char*>::iterator i = newArgv.begin(), e = newArgv.end();
 778          i != e; ++i)
 779       free(*i);
 780   }
 781
 782   DEBUG(dbgs() << "Args: ";
 783         for (int i = 0; i < argc; ++i)
 784           dbgs() << argv[i] << ' ';
 785         dbgs() << '\n';
 786        );
 787
 788   // If we had an error processing our arguments, don't let the program execute
 789   if (ErrorParsing) exit(1);
 790 }
 791
 792 //===----------------------------------------------------------------------===//
 793 // Option Base class implementation
 794 //
 795
 796 bool Option::error(const Twine &Message, StringRef ArgName) {
 797   if (ArgName.data() == 0) ArgName = ArgStr;
 798   if (ArgName.empty())
 799     errs() << HelpStr;  // Be nice for positional arguments
 800   else
 801     errs() << ProgramName << ": for the -" << ArgName;
 802
 803   errs() << " option: " << Message << "\n";
 804   return true;
 805 }
 806
 807 bool Option::addOccurrence(unsigned pos, StringRef ArgName,
 808                            StringRef Value, bool MultiArg) {
 809   if (!MultiArg)
 810     NumOccurrences++;   // Increment the number of times we have been seen
 811
 812   switch (getNumOccurrencesFlag()) {
 813   case Optional:
 814     if (NumOccurrences > 1)
 815       return error("may only occur zero or one times!", ArgName);
 816     break;
 817   case Required:
 818     if (NumOccurrences > 1)
 819       return error("must occur exactly one time!", ArgName);
 820     // Fall through
 821   case OneOrMore:
 822   case ZeroOrMore:
 823   case ConsumeAfter: break;
 824   default: return error("bad num occurrences flag value!");
 825   }
 826
 827   return handleOccurrence(pos, ArgName, Value);
 828 }
 829
 830
 831 // getValueStr - Get the value description string, using "DefaultMsg" if nothing
 832 // has been specified yet.
 833 //
 834 static const char *getValueStr(const Option &O, const char *DefaultMsg) {
 835   if (O.ValueStr[0] == 0) return DefaultMsg;
 836   return O.ValueStr;
 837 }
 838
 839 //===----------------------------------------------------------------------===//
 840 // cl::alias class implementation
 841 //
 842
 843 // Return the width of the option tag for printing...
 844 size_t alias::getOptionWidth() const {
 845   return std::strlen(ArgStr)+6;
 846 }
 847
 848 // Print out the option for the alias.
 849 void alias::printOptionInfo(size_t GlobalWidth) const {
 850   size_t L = std::strlen(ArgStr);
 851   errs() << "  -" << ArgStr;
 852   errs().indent(GlobalWidth-L-6) << " - " << HelpStr << "\n";
 853 }
 854
 855
 856
 857 //===----------------------------------------------------------------------===//
 858 // Parser Implementation code...
 859 //
 860
 861 // basic_parser implementation
 862 //
 863
 864 // Return the width of the option tag for printing...
 865 size_t basic_parser_impl::getOptionWidth(const Option &O) const {
 866   size_t Len = std::strlen(O.ArgStr);
 867   if (const char *ValName = getValueName())
 868     Len += std::strlen(getValueStr(O, ValName))+3;
 869
 870   return Len + 6;
 871 }
 872
 873 // printOptionInfo - Print out information about this option.  The
 874 // to-be-maintained width is specified.
 875 //
 876 void basic_parser_impl::printOptionInfo(const Option &O,
 877                                         size_t GlobalWidth) const {
 878   outs() << "  -" << O.ArgStr;
 879
 880   if (const char *ValName = getValueName())
 881     outs() << "=<" << getValueStr(O, ValName) << '>';
 882
 883   outs().indent(GlobalWidth-getOptionWidth(O)) << " - " << O.HelpStr << '\n';
 884 }
 885
 886
 887
 888
 889 // parser<bool> implementation
 890 //
 891 bool parser<bool>::parse(Option &O, StringRef ArgName,
 892                          StringRef Arg, bool &Value) {
 893   if (Arg == "" || Arg == "true" || Arg == "TRUE" || Arg == "True" ||
 894       Arg == "1") {
 895     Value = true;
 896     return false;
 897   }
 898
 899   if (Arg == "false" || Arg == "FALSE" || Arg == "False" || Arg == "0") {
 900     Value = false;
 901     return false;
 902   }
 903   return O.error("'" + Arg +
 904                  "' is invalid value for boolean argument! Try 0 or 1");
 905 }
 906
 907 // parser<boolOrDefault> implementation
 908 //
 909 bool parser<boolOrDefault>::parse(Option &O, StringRef ArgName,
 910                                   StringRef Arg, boolOrDefault &Value) {
 911   if (Arg == "" || Arg == "true" || Arg == "TRUE" || Arg == "True" ||
 912       Arg == "1") {
 913     Value = BOU_TRUE;
 914     return false;
 915   }
 916   if (Arg == "false" || Arg == "FALSE" || Arg == "False" || Arg == "0") {
 917     Value = BOU_FALSE;
 918     return false;
 919   }
 920
 921   return O.error("'" + Arg +
 922                  "' is invalid value for boolean argument! Try 0 or 1");
 923 }
 924
 925 // parser<int> implementation
 926 //
 927 bool parser<int>::parse(Option &O, StringRef ArgName,
 928                         StringRef Arg, int &Value) {
 929   if (Arg.getAsInteger(0, Value))
 930     return O.error("'" + Arg + "' value invalid for integer argument!");
 931   return false;
 932 }
 933
 934 // parser<unsigned> implementation
 935 //
 936 bool parser<unsigned>::parse(Option &O, StringRef ArgName,
 937                              StringRef Arg, unsigned &Value) {
 938
 939   if (Arg.getAsInteger(0, Value))
 940     return O.error("'" + Arg + "' value invalid for uint argument!");
 941   return false;
 942 }
 943
 944 // parser<double>/parser<float> implementation
 945 //
 946 static bool parseDouble(Option &O, StringRef Arg, double &Value) {
 947   SmallString<32> TmpStr(Arg.begin(), Arg.end());
 948   const char *ArgStart = TmpStr.c_str();
 949   char *End;
 950   Value = strtod(ArgStart, &End);
 951   if (*End != 0)
 952     return O.error("'" + Arg + "' value invalid for floating point argument!");
 953   return false;
 954 }
 955
 956 bool parser<double>::parse(Option &O, StringRef ArgName,
 957                            StringRef Arg, double &Val) {
 958   return parseDouble(O, Arg, Val);
 959 }
 960
 961 bool parser<float>::parse(Option &O, StringRef ArgName,
 962                           StringRef Arg, float &Val) {
 963   double dVal;
 964   if (parseDouble(O, Arg, dVal))
 965     return true;
 966   Val = (float)dVal;
 967   return false;
 968 }
 969
 970
 971
 972 // generic_parser_base implementation
 973 //
 974
 975 // findOption - Return the option number corresponding to the specified
 976 // argument string.  If the option is not found, getNumOptions() is returned.
 977 //
 978 unsigned generic_parser_base::findOption(const char *Name) {
 979   unsigned e = getNumOptions();
 980
 981   for (unsigned i = 0; i != e; ++i) {
 982     if (strcmp(getOption(i), Name) == 0)
 983       return i;
 984   }
 985   return e;
 986 }
 987
 988
 989 // Return the width of the option tag for printing...
 990 size_t generic_parser_base::getOptionWidth(const Option &O) const {
 991   if (O.hasArgStr()) {
 992     size_t Size = std::strlen(O.ArgStr)+6;
 993     for (unsigned i = 0, e = getNumOptions(); i != e; ++i)
 994       Size = std::max(Size, std::strlen(getOption(i))+8);
 995     return Size;
 996   } else {
 997     size_t BaseSize = 0;
 998     for (unsigned i = 0, e = getNumOptions(); i != e; ++i)
 999       BaseSize = std::max(BaseSize, std::strlen(getOption(i))+8);
1000     return BaseSize;
1001   }
1002 }
1003
1004 // printOptionInfo - Print out information about this option.  The
1005 // to-be-maintained width is specified.
1006 //
1007 void generic_parser_base::printOptionInfo(const Option &O,
1008                                           size_t GlobalWidth) const {
1009   if (O.hasArgStr()) {
1010     size_t L = std::strlen(O.ArgStr);
1011     outs() << "  -" << O.ArgStr;
1012     outs().indent(GlobalWidth-L-6) << " - " << O.HelpStr << '\n';
1013
1014     for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
1015       size_t NumSpaces = GlobalWidth-strlen(getOption(i))-8;
1016       outs() << "    =" << getOption(i);
1017       outs().indent(NumSpaces) << " -   " << getDescription(i) << '\n';
1018     }
1019   } else {
1020     if (O.HelpStr[0])
1021       outs() << "  " << O.HelpStr << '\n';
1022     for (unsigned i = 0, e = getNumOptions(); i != e; ++i) {
1023       size_t L = std::strlen(getOption(i));
1024       outs() << "    -" << getOption(i);
1025       outs().indent(GlobalWidth-L-8) << " - " << getDescription(i) << '\n';
1026     }
1027   }
1028 }
1029
1030
1031 //===----------------------------------------------------------------------===//
1032 // -help and -help-hidden option implementation
1033 //
1034
1035 static int OptNameCompare(const void *LHS, const void *RHS) {
1036   typedef std::pair<const char *, Option*> pair_ty;
1037
1038   return strcmp(((pair_ty*)LHS)->first, ((pair_ty*)RHS)->first);
1039 }
1040
1041 namespace {
1042
1043 class HelpPrinter {
1044   size_t MaxArgLen;
1045   const Option *EmptyArg;
1046   const bool ShowHidden;
1047
1048 public:
1049   explicit HelpPrinter(bool showHidden) : ShowHidden(showHidden) {
1050     EmptyArg = 0;
1051   }
1052
1053   void operator=(bool Value) {
1054     if (Value == false) return;
1055
1056     // Get all the options.
1057     SmallVector<Option*, 4> PositionalOpts;
1058     SmallVector<Option*, 4> SinkOpts;
1059     StringMap<Option*> OptMap;
1060     GetOptionInfo(PositionalOpts, SinkOpts, OptMap);
1061
1062     // Copy Options into a vector so we can sort them as we like.
1063     SmallVector<std::pair<const char *, Option*>, 128> Opts;
1064     SmallPtrSet<Option*, 128> OptionSet;  // Duplicate option detection.
1065
1066     for (StringMap<Option*>::iterator I = OptMap.begin(), E = OptMap.end();
1067          I != E; ++I) {
1068       // Ignore really-hidden options.
1069       if (I->second->getOptionHiddenFlag() == ReallyHidden)
1070         continue;
1071
1072       // Unless showhidden is set, ignore hidden flags.
1073       if (I->second->getOptionHiddenFlag() == Hidden && !ShowHidden)
1074         continue;
1075
1076       // If we've already seen this option, don't add it to the list again.
1077       if (!OptionSet.insert(I->second))
1078         continue;
1079
1080       Opts.push_back(std::pair<const char *, Option*>(I->getKey().data(),
1081                                                       I->second));
1082     }
1083
1084     // Sort the options list alphabetically.
1085     qsort(Opts.data(), Opts.size(), sizeof(Opts[0]), OptNameCompare);
1086
1087     if (ProgramOverview)
1088       outs() << "OVERVIEW: " << ProgramOverview << "\n";
1089
1090     outs() << "USAGE: " << ProgramName << " [options]";
1091
1092     // Print out the positional options.
1093     Option *CAOpt = 0;   // The cl::ConsumeAfter option, if it exists...
1094     if (!PositionalOpts.empty() &&
1095         PositionalOpts[0]->getNumOccurrencesFlag() == ConsumeAfter)
1096       CAOpt = PositionalOpts[0];
1097
1098     for (size_t i = CAOpt != 0, e = PositionalOpts.size(); i != e; ++i) {
1099       if (PositionalOpts[i]->ArgStr[0])
1100         outs() << " --" << PositionalOpts[i]->ArgStr;
1101       outs() << " " << PositionalOpts[i]->HelpStr;
1102     }
1103
1104     // Print the consume after option info if it exists...
1105     if (CAOpt) outs() << " " << CAOpt->HelpStr;
1106
1107     outs() << "\n\n";
1108
1109     // Compute the maximum argument length...
1110     MaxArgLen = 0;
1111     for (size_t i = 0, e = Opts.size(); i != e; ++i)
1112       MaxArgLen = std::max(MaxArgLen, Opts[i].second->getOptionWidth());
1113
1114     outs() << "OPTIONS:\n";
1115     for (size_t i = 0, e = Opts.size(); i != e; ++i)
1116       Opts[i].second->printOptionInfo(MaxArgLen);
1117
1118     // Print any extra help the user has declared.
1119     for (std::vector<const char *>::iterator I = MoreHelp->begin(),
1120           E = MoreHelp->end(); I != E; ++I)
1121       outs() << *I;
1122     MoreHelp->clear();
1123
1124     // Halt the program since help information was printed
1125     exit(1);
1126   }
1127 };
1128 } // End anonymous namespace
1129
1130 // Define the two HelpPrinter instances that are used to print out help, or
1131 // help-hidden...
1132 //
1133 static HelpPrinter NormalPrinter(false);
1134 static HelpPrinter HiddenPrinter(true);
1135
1136 static cl::opt<HelpPrinter, true, parser<bool> >
1137 HOp("help", cl::desc("Display available options (-help-hidden for more)"),
1138     cl::location(NormalPrinter), cl::ValueDisallowed);
1139
1140 static cl::opt<HelpPrinter, true, parser<bool> >
1141 HHOp("help-hidden", cl::desc("Display all available options"),
1142      cl::location(HiddenPrinter), cl::Hidden, cl::ValueDisallowed);
1143
1144 static void (*OverrideVersionPrinter)() = 0;
1145
1146 static int TargetArraySortFn(const void *LHS, const void *RHS) {
1147   typedef std::pair<const char *, const Target*> pair_ty;
1148   return strcmp(((const pair_ty*)LHS)->first, ((const pair_ty*)RHS)->first);
1149 }
1150
1151 namespace {
1152 class VersionPrinter {
1153 public:
1154   void print() {
1155     raw_ostream &OS = outs();
1156     OS << "Low Level Virtual Machine (http://llvm.org/):\n"
1157        << "  " << PACKAGE_NAME << " version " << PACKAGE_VERSION;
1158 #ifdef LLVM_VERSION_INFO
1159     OS << LLVM_VERSION_INFO;
1160 #endif
1161     OS << "\n  ";
1162 #ifndef __OPTIMIZE__
1163     OS << "DEBUG build";
1164 #else
1165     OS << "Optimized build";
1166 #endif
1167 #ifndef NDEBUG
1168     OS << " with assertions";
1169 #endif
1170     std::string CPU = sys::getHostCPUName();
1171     if (CPU == "generic") CPU = "(unknown)";
1172     OS << ".\n"
1173 #if (ENABLE_TIMESTAMPS == 1)
1174        << "  Built " << __DATE__ << " (" << __TIME__ << ").\n"
1175 #endif
1176        << "  Host: " << sys::getHostTriple() << '\n'
1177        << "  Host CPU: " << CPU << '\n'
1178        << '\n'
1179        << "  Registered Targets:\n";
1180
1181     std::vector<std::pair<const char *, const Target*> > Targets;
1182     size_t Width = 0;
1183     for (TargetRegistry::iterator it = TargetRegistry::begin(),
1184            ie = TargetRegistry::end(); it != ie; ++it) {
1185       Targets.push_back(std::make_pair(it->getName(), &*it));
1186       Width = std::max(Width, strlen(Targets.back().first));
1187     }
1188     if (!Targets.empty())
1189       qsort(&Targets[0], Targets.size(), sizeof(Targets[0]),
1190             TargetArraySortFn);
1191
1192     for (unsigned i = 0, e = Targets.size(); i != e; ++i) {
1193       OS << "    " << Targets[i].first;
1194       OS.indent(Width - strlen(Targets[i].first)) << " - "
1195              << Targets[i].second->getShortDescription() << '\n';
1196     }
1197     if (Targets.empty())
1198       OS << "    (none)\n";
1199   }
1200   void operator=(bool OptionWasSpecified) {
1201     if (!OptionWasSpecified) return;
1202
1203     if (OverrideVersionPrinter == 0) {
1204       print();
1205       exit(1);
1206     }
1207     (*OverrideVersionPrinter)();
1208     exit(1);
1209   }
1210 };
1211 } // End anonymous namespace
1212
1213
1214 // Define the --version option that prints out the LLVM version for the tool
1215 static VersionPrinter VersionPrinterInstance;
1216
1217 static cl::opt<VersionPrinter, true, parser<bool> >
1218 VersOp("version", cl::desc("Display the version of this program"),
1219     cl::location(VersionPrinterInstance), cl::ValueDisallowed);
1220
1221 // Utility function for printing the help message.
1222 void cl::PrintHelpMessage() {
1223   // This looks weird, but it actually prints the help message. The
1224   // NormalPrinter variable is a HelpPrinter and the help gets printed when
1225   // its operator= is invoked. That's because the "normal" usages of the
1226   // help printer is to be assigned true/false depending on whether the
1227   // -help option was given or not. Since we're circumventing that we have
1228   // to make it look like -help was given, so we assign true.
1229   NormalPrinter = true;
1230 }
1231
1232 /// Utility function for printing version number.
1233 void cl::PrintVersionMessage() {
1234   VersionPrinterInstance.print();
1235 }
1236
1237 void cl::SetVersionPrinter(void (*func)()) {
1238   OverrideVersionPrinter = func;
1239 }