Re-committing http://codereview.chromium.org/8736001/ originally committed revision=112305

third_party/libphonenumber/cpp/src/logger.h

-// Copyright (C) 2011 Google Inc.
-//
-// Licensed 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.
-
-// Author: Philippe Liard
-
-#ifndef I18N_PHONENUMBERS_LOGGER_H_
-#define I18N_PHONENUMBERS_LOGGER_H_
-
-#include <cstdio>
-#include <string>
-
-#include "base/memory/scoped_ptr.h"
-
-namespace i18n {
-namespace phonenumbers {
-
-using std::string;
-
-enum LogLevel {
-  LOG_FATAL = 1,
-  LOG_ERROR,
-  LOG_WARNING,
-  LOG_INFO,
-  LOG_DEBUG,
-};
-
-enum {
-  DFATAL = LOG_FATAL,
-// ERROR seems to be defined on MSVC, therefore don't overwrite it.
-#ifndef ERROR
-  ERROR = LOG_ERROR,
-#endif
-  WARNING = LOG_WARNING,
-};
-
-// Subclass this abstract class to override the way logging is handled in the
-// library. You can then call the PhoneNumberUtil::SetLogger() method.
-class Logger {
- public:
-  Logger() : level_(LOG_ERROR) {}
-  virtual ~Logger() {}
-
-  // Writes the message level to the underlying output stream.
-  virtual void WriteLevel() {}
-  // Writes the provided message to the underlying output stream.
-  virtual void WriteMessage(const string& msg) = 0;
-
-  inline LogLevel level() const {
-    return level_;
-  }
-
-  inline void set_level(LogLevel level) {
-    level_ = level;
-  }
-
-  static inline void set_logger_impl(Logger* logger) {
-    impl_ = logger;
-  }
-
-  static inline Logger* mutable_logger_impl() {
-    return impl_;
-  }
-
- private:
-  static Logger* impl_;
-  LogLevel level_;
-};
-
-// Logger that does not log anything. It could be useful to "mute" the
-// phonenumber library.
-class NullLogger : public Logger {
- public:
-  virtual ~NullLogger() {}
-
-  virtual void WriteMessage(const string& /* msg */) {}
-};
-
-}  // namespace phonenumbers
-}  // namespace i18n
-
-#endif  // I18N_PHONENUMBERS_LOGGER_ADAPTER_H_