// Licensed to the Apache Software Foundation (ASF) under one

// or more contributor license agreements.  See the NOTICE file

// distributed with this work for additional information

// regarding copyright ownership.  The ASF licenses this file

// to you under the Apache License, Version 2.0 (the

// "License"); you may not use this file except in compliance

// with the License.  You may obtain a copy of the License at

//

//   http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing,

// software distributed under the License is distributed on an

// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

// KIND, either express or implied.  See the License for the

// specific language governing permissions and limitations

// under the License.

// Date: Sun Aug  9 12:26:03 CST 2015

#ifndef  BVAR_GFLAG_H

#define  BVAR_GFLAG_H

#include <string>                       // std::string

#include "bvar/variable.h"

namespace bvar {

// Expose important gflags as bvar so that they're monitored.

class GFlag : public Variable {

public:

    GFlag(const butil::StringPiece& gflag_name);

    GFlag(const butil::StringPiece& prefix,

          const butil::StringPiece& gflag_name);

    // Calling hide() in dtor manually is a MUST required by Variable.

    ~GFlag() { hide(); }

    void describe(std::ostream& os, bool quote_string) const override;

#ifdef BAIDU_INTERNAL

    void get_value(boost::any* value) const override;

#endif

    // Get value of the gflag.

    // We don't bother making the return type generic. This function

    // is just for consistency with other classes.

    std::string get_value() const;

    // Set the gflag with a new value.

    // Returns true on success.

    bool set_value(const char* value);

    // name of the gflag.

    const std::string& gflag_name() const {

        return _gflag_name.empty() ? name() : _gflag_name;

    }

private:

    std::string _gflag_name;

};

}  // namespace bvar

#endif  //BVAR_GFLAG_H