path: root/lib/Support/CommandLine.cpp

//===-- CommandLine.cpp - Command line parser implementation --------------===//
// 
//                     The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
// 
//===----------------------------------------------------------------------===//
//
// This class implements a command line argument processor that is useful when
// creating a tool.  It provides a simple, minimalistic interface that is easily
// extensible and supports nonlocal (library) command line options.
//
// Note that rather than trying to figure out what this code does, you could try
// reading the library documentation located in docs/CommandLine.html
//
//===----------------------------------------------------------------------===//

#include "Config/config.h"
#include "Support/CommandLine.h"
#include <algorithm>
#include <map>
#include <set>
#include <iostream>
#include <cstdlib>
#include <cerrno>
#include <cstring>
using namespace llvm;

using namespace cl;

// Globals for name and overview of program
static const char *ProgramName = "<unknown>";
static const char *ProgramOverview = 0;

//===----------------------------------------------------------------------===//
// Basic, shared command line option processing machinery...
//

// Return the global command line option vector.  Making it a function scoped
// static ensures that it will be initialized correctly before its first use.
//
static std::map<std::string, Option*> *CommandLineOptions = 0;
static std::map<std::string, Option*> &getOpts() {
  if (CommandLineOptions == 0)
    CommandLineOptions = new std::map<std::string,Option*>();
  return *CommandLineOptions;
}

static Option *getOption(const std::string &Str) {
  if (CommandLineOptions == 0) return 0;
  std::map<std::string,Option*>::iterator I = CommandLineOptions->find(Str);
  return I != CommandLineOptions->end() ? I->second : 0;
}

static std::vector<Option*> &getPositionalOpts() {
  static std::vector<Option*> *Positional = 0;
  if (!Positional) Positional = new std::vector<Option*>();
  return *Positional;
}

static void AddArgument(const char *ArgName, Option *Opt) {
  if (getOption(ArgName)) {
    std::cerr << ProgramName << ": CommandLine Error: Argument '" 
              << ArgName << "' defined more than once!\n";
  } else {
    // Add argument to the argument map!
    getOpts()[ArgName] = Opt;
  }
}

// RemoveArgument - It's possible that the argument is no longer in the map if
// options have already been processed and the map has been deleted!
// 
static void RemoveArgument(const char *ArgName, Option *Opt) {
  if (CommandLineOptions == 0) return;
#ifndef NDEBUG
  // This disgusting HACK is brought to you courtesy of GCC 3.3.2, which ICE's
  // If we pass ArgName directly into getOption here.
  std::string Tmp = ArgName;
  assert(getOption(Tmp) == Opt && "Arg not in map!");
#endif
  CommandLineOptions->erase(ArgName);
  if (CommandLineOptions->empty()) {
    delete CommandLineOptions;
    CommandLineOptions = 0;
  }
}

static inline bool ProvideOption(Option *Handler, const char *ArgName,
                                 const char *Value, int argc, char **argv,
                                 int &i) {
  // Enforce value requirements
  switch (Handler->getValueExpectedFlag()) {
  case ValueRequired:
    if (Value == 0 || *Value == 0) {  // No value specified?
      if (i+1 < argc) {     // Steal the next argument, like for '-o filename'
        Value = argv[++i];
      } else {
        return Handler->error(" requires a value!");
      }
    }
    break;
  case ValueDisallowed:
    if (*Value != 0)
      return Handler->error(" does not allow a value! '" + 
                            std::string(Value) + "' specified.");
    break;
  case ValueOptional: 
    break;
  default: 
    std::cerr << ProgramName 
              << ": Bad ValueMask flag! CommandLine usage error:" 
              << Handler->getValueExpectedFlag() << "\n"; 
    abort();
    break;
  }

  // Run the handler now!
  return Handler->addOccurrence(i, ArgName, Value);
}

static bool ProvidePositionalOption(Option *Handler, const std::string &Arg, 
                                    int i) {
  int Dummy = i;
  return ProvideOption(Handler, Handler->ArgStr, Arg.c_str(), 0, 0, Dummy);
}


// Option predicates...
static inline bool isGrouping(const Option *