1 // Copyright (C) 2011 The Libphonenumber Authors 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 // Author: Philippe Liard 16 17 #ifndef I18N_PHONENUMBERS_DEFAULT_LOGGER_H_ 18 #define I18N_PHONENUMBERS_DEFAULT_LOGGER_H_ 19 20 #include "phonenumbers/logger.h" 21 22 #include <sstream> 23 #include <string> 24 25 namespace i18n { 26 namespace phonenumbers { 27 28 using i18n::phonenumbers::Logger; 29 using std::string; 30 using std::stringstream; 31 32 // Class template used to inline the right implementation for the T -> string 33 // conversion. 34 template <typename T> 35 struct ConvertToString; 36 37 template <typename T> 38 struct ConvertToString { DoWorkConvertToString39 static inline string DoWork(const T& s) { 40 return string(s); 41 } 42 }; 43 44 template <> 45 struct ConvertToString<int> { 46 static inline string DoWork(int n) { 47 stringstream stream; 48 stream << n; 49 string result; 50 stream >> result; 51 return result; 52 } 53 }; 54 55 class LoggerHandler { 56 public: 57 LoggerHandler(Logger* impl) : impl_(impl) {} 58 59 ~LoggerHandler() { 60 if (impl_) { 61 impl_->WriteMessage("\n"); 62 } 63 } 64 65 template <typename T> 66 LoggerHandler& operator<<(const T& value) { 67 if (impl_) { 68 impl_->WriteMessage(ConvertToString<T>::DoWork(value)); 69 } 70 return *this; 71 } 72 73 private: 74 Logger* const impl_; 75 }; 76 77 inline LoggerHandler LOG(int n) { 78 Logger* const logger_impl = Logger::mutable_logger_impl(); 79 if (logger_impl->level() < n) { 80 return LoggerHandler(NULL); 81 } 82 logger_impl->WriteLevel(); 83 return LoggerHandler(logger_impl); 84 } 85 86 inline LoggerHandler VLOG(int n) { 87 // VLOG(1) is the next logging level after LOG(DEBUG). 88 n += LOG_DEBUG; 89 return LOG(n); 90 } 91 92 // Default logger implementation used by PhoneNumberUtil class. It outputs the 93 // messages to the standard output. 94 class StdoutLogger : public Logger { 95 public: 96 virtual ~StdoutLogger() {} 97 98 virtual void WriteLevel(); 99 virtual void WriteMessage(const string& msg); 100 }; 101 102 } // namespace phonenumbers 103 } // namespace i18n 104 105 #endif // I18N_PHONENUMBERS_DEFAULT_LOGGER_H_ 106