vcore/src/dpl/log/include/dpl/log/log.h

   1 /*
   2  * Copyright (c) 2011 Samsung Electronics Co., Ltd All Rights Reserved
   3  *
   4  *    Licensed under the Apache License, Version 2.0 (the "License");
   5  *    you may not use this file except in compliance with the License.
   6  *    You may obtain a copy of the License at
   7  *
   8  *        http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  *    Unless required by applicable law or agreed to in writing, software
  11  *    distributed under the License is distributed on an "AS IS" BASIS,
  12  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  *    See the License for the specific language governing permissions and
  14  *    limitations under the License.
  15  */
  16 /*
  17  * @file        log.h
  18  * @author      Przemyslaw Dobrowolski (p.dobrowolsk@samsung.com)
  19  * @version     1.0
  20  * @brief       This file is the implementation file of log system
  21  */
  22 #ifndef DPL_LOG_H
  23 #define DPL_LOG_H
  24
  25 #include <sstream>
  26 #include <list>
  27 #include <unordered_map>
  28 #include <string>
  29
  30 #include <dpl/singleton.h>
  31 #include <dpl/noncopyable.h>
  32
  33 #include <dpl/log/abstract_log_provider.h>
  34
  35 namespace VcoreDPL {
  36 namespace Log {
  37 /**
  38  * DPL log system
  39  *
  40  * To switch logs into old style, export
  41  * DPL_USE_OLD_STYLE_LOGS before application start
  42  */
  43 class LogSystem : private Noncopyable
  44 {
  45 public:
  46     LogSystem();
  47     virtual ~LogSystem();
  48
  49     AbstractLogProvider::LogLevel GetLogLevel() const { return m_level; }
  50
  51     void Log(AbstractLogProvider::LogLevel level,
  52              const char *message,
  53              const char *filename,
  54              int line,
  55              const char *function) const;
  56
  57
  58     /**
  59      * Set default's DLOG provider Tag
  60      */
  61     void SetTag(const char *tag);
  62
  63     /**
  64      * Add abstract provider to providers list
  65      *
  66      * @notice Ownership is transfered to LogSystem and deleted upon exit
  67      */
  68     void AddProvider(AbstractLogProvider *provider);
  69
  70     /**
  71      * Remove abstract provider from providers list
  72      */
  73     void RemoveProvider(AbstractLogProvider *provider);
  74
  75     /**
  76      * Selects given provider by name (overwrites environment setting)
  77      *
  78      * Throws std::out_of_range exception if not found.
  79      */
  80     void SelectProvider(const std::string& name);
  81
  82     /**
  83      * Sets log level (overwrites environment settings)
  84      */
  85     void SetLogLevel(const char* level);
  86
  87 private:
  88     void RemoveProviders();
  89
  90     typedef std::list<AbstractLogProvider *> AbstractLogProviderPtrList;
  91     AbstractLogProviderPtrList m_providers;
  92     AbstractLogProvider::LogLevel m_level;
  93
  94     typedef AbstractLogProvider *(*ProviderFn)();
  95     /*
  96      * It cannot be global as it is used in library constructor and we can't be sure which
  97      * constructor is called first: library's or new_provider's.
  98      */
  99     std::unordered_map<std::string, ProviderFn> m_providerCtor;
 100 };
 101
 102 /*
 103  * Replacement low overhead null logging class
 104  */
 105 class NullStream
 106 {
 107   public:
 108     NullStream() {}
 109
 110     template <typename T>
 111     NullStream& operator<<(const T&)
 112     {
 113         return *this;
 114     }
 115 };
 116
 117 /**
 118  * Log system singleton
 119  */
 120 typedef Singleton<LogSystem> LogSystemSingleton;
 121 }
 122 } // namespace VcoreDPL
 123
 124
 125 /* avoid warnings about unused variables */
 126 #define DPL_MACRO_DUMMY_LOGGING(message, level)                                 \
 127     do {                                                                        \
 128         VcoreDPL::Log::NullStream ns;                                           \
 129         ns << message;                                                          \
 130     } while (0)
 131
 132 #define DPL_MACRO_FOR_LOGGING(message, level)                                   \
 133 do                                                                              \
 134 {                                                                               \
 135     if (level > VcoreDPL::Log::AbstractLogProvider::LogLevel::None &&           \
 136         VcoreDPL::Log::LogSystemSingleton::Instance().GetLogLevel() >= level)   \
 137     {                                                                           \
 138         std::ostringstream platformLog;                                         \
 139         platformLog << message;                                                 \
 140         VcoreDPL::Log::LogSystemSingleton::Instance().Log(level,                \
 141                                                      platformLog.str().c_str(), \
 142                                                      __FILE__,                  \
 143                                                      __LINE__,                  \
 144                                                      __FUNCTION__);             \
 145     }                                                                           \
 146 } while (0)
 147
 148 #define  LogError(message) DPL_MACRO_FOR_LOGGING(message, VcoreDPL::Log::AbstractLogProvider::LogLevel::Error)
 149
 150 #ifdef BUILD_TYPE_DEBUG
 151     #define LogDebug(message)    DPL_MACRO_FOR_LOGGING(message, VcoreDPL::Log::AbstractLogProvider::LogLevel::Debug)
 152     #define LogInfo(message)     DPL_MACRO_FOR_LOGGING(message, VcoreDPL::Log::AbstractLogProvider::LogLevel::Info)
 153     #define LogWarning(message)  DPL_MACRO_FOR_LOGGING(message, VcoreDPL::Log::AbstractLogProvider::LogLevel::Warning)
 154     #define LogPedantic(message) DPL_MACRO_FOR_LOGGING(message, VcoreDPL::Log::AbstractLogProvider::LogLevel::Pedantic)
 155 #else
 156     #define LogDebug(message)    DPL_MACRO_DUMMY_LOGGING(message, VcoreDPL::Log::AbstractLogProvider::LogLevel::Debug)
 157     #define LogInfo(message)     DPL_MACRO_DUMMY_LOGGING(message, VcoreDPL::Log::AbstractLogProvider::LogLevel::Info)
 158     #define LogWarning(message)  DPL_MACRO_DUMMY_LOGGING(message, VcoreDPL::Log::AbstractLogProvider::LogLevel::Warning)
 159     #define LogPedantic(message) DPL_MACRO_DUMMY_LOGGING(message, VcoreDPL::Log::AbstractLogProvider::LogLevel::Pedantic)
 160 #endif // BUILD_TYPE_DEBUG
 161
 162 #endif // DPL_LOG_H