hadoop/hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/lib/common/logging.h

/**
 * 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.
 */

#ifndef LIB_COMMON_LOGGING_H_
#define LIB_COMMON_LOGGING_H_

#include <iostream>

namespace hdfs {

enum LogLevel {
  kDebug,
  kInfo,
  kWarning,
  kError,
};

#define LOG_DEBUG() LogMessage(kDebug)
#define LOG_INFO() LogMessage(kInfo)
#define LOG_WARN() LogMessage(kWarning)
#define LOG_ERROR() LogMessage(kError)

class LogMessage {
 public:
  LogMessage(const LogLevel &l) {
    static constexpr const char * kLogLevelMessage[] = {"DEBUG", "INFO", "WARN", "ERROR"};
    ::std::cerr << "[" << kLogLevelMessage[(size_t)l] << "] ";
  }

  ~LogMessage() {
    ::std::cerr << std::endl;
  }

  LogMessage& operator<<(const std::string& msg) {
    ::std::cerr << msg;
    return *this;
  }
  LogMessage& operator<<(int x) {
    ::std::cerr << x;
    return *this;
  }
};

}

#endif