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_LOGGER_H_
18#define I18N_PHONENUMBERS_LOGGER_H_
19
20#include <cstdio>
21#include <string>
22
23namespace i18n {
24namespace phonenumbers {
25
26using std::string;
27
28enum {
29  LOG_FATAL = 1,
30  LOG_ERROR,
31  LOG_WARNING,
32  LOG_INFO,
33  LOG_DEBUG,
34};
35
36enum {
37  DFATAL = LOG_FATAL,
38// ERROR seems to be defined on MSVC, therefore don't overwrite it.
39#ifndef ERROR
40  ERROR = LOG_ERROR,
41#endif
42  WARNING = LOG_WARNING,
43};
44
45// Subclass this abstract class to override the way logging is handled in the
46// library. You can then call the PhoneNumberUtil::SetLogger() method.
47class Logger {
48 public:
49  Logger() : level_(LOG_ERROR) {}
50  virtual ~Logger() {}
51
52  // Writes the message level to the underlying output stream.
53  virtual void WriteLevel() {}
54  // Writes the provided message to the underlying output stream.
55  virtual void WriteMessage(const string& msg) = 0;
56
57  // Note that if set_verbosity_level has been used to set the level to a value
58  // that is not represented by an enum, the result here will be a log
59  // level that is higher than LOG_DEBUG.
60  inline int level() const {
61    return level_;
62  }
63
64  inline void set_level(int level) {
65    level_ = level;
66  }
67
68  // If you want to see verbose logs in addition to other logs, use this method.
69  // This will result in all log messages at the levels above being shown, along
70  // with calls to VLOG with the verbosity level set to this level or lower.
71  // For example, set_verbosity_level(2) will show calls of VLOG(1) and VLOG(2)
72  // but not VLOG(3), along with all calls to LOG().
73  inline void set_verbosity_level(int verbose_logs_level) {
74    set_level(LOG_DEBUG + verbose_logs_level);
75  }
76
77  static inline Logger* set_logger_impl(Logger* logger) {
78    impl_ = logger;
79    return logger;
80  }
81
82  static inline Logger* mutable_logger_impl() {
83    return impl_;
84  }
85
86 private:
87  static Logger* impl_;
88  int level_;
89};
90
91// Logger that does not log anything. It could be useful to "mute" the
92// phonenumber library.
93class NullLogger : public Logger {
94 public:
95  virtual ~NullLogger() {}
96
97  virtual void WriteMessage(const string& /* msg */) {}
98};
99
100}  // namespace phonenumbers
101}  // namespace i18n
102
103#endif  // I18N_PHONENUMBERS_LOGGER_ADAPTER_H_
104