configreader.h

// Copyright (c) 2011-2014 Zeex
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice,
//    this list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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#include <map>
#include <sstream>
#include <string>

#ifndef CONFIGREADER_H
#define CONFIGREADER_H

class ConfigReader {
 public:
  typedef std::map<std::string, std::string> OptionMap;

  ConfigReader();
  ConfigReader(const std::string &filename);

  bool LoadFile(const std::string &filename);

  template<typename T>
  void GetOption(const std::string &name, T &value) const;

  template<typename T>
  T GetOptionDefault(const std::string &name, const T &defaultValue) const;

  bool IsLoaded() const { return loaded_; }

 private:
  bool loaded_;  
  OptionMap options_;
};

template<typename T>
void ConfigReader::GetOption(const std::string &name, T &value) const {
  value = GetOptionDefault(name, value);
}

template<typename T>
T ConfigReader::GetOptionDefault(const std::string &name,
                                 const T &default_) const {
  OptionMap::const_iterator iterator = options_.find(name);
  if (iterator != options_.end()) {
    std::stringstream sstream(iterator->second);
    T value;
    sstream >> value;
    if (sstream) {
      return value;
    }
  }
  return default_;
}

#endif // !CONFIGREADER_H