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
25namespace i18n {
26namespace phonenumbers {
27
28using i18n::phonenumbers::Logger;
29using std::string;
30using std::stringstream;
31
32// Class template used to inline the right implementation for the T -> string
33// conversion.
34template <typename T>
35struct ConvertToString;
36
37template <typename T>
38struct ConvertToString {
39  static inline string DoWork(const T& s) {
40    return string(s);
41  }
42};
43
44template <>
45struct 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
55class 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
77inline 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
86inline 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.
94class 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