1 // Copyright 2012 The Chromium Authors 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef BASE_LOGGING_WIN_H_ 6 #define BASE_LOGGING_WIN_H_ 7 8 #include <stddef.h> 9 10 #include <string> 11 12 #include "base/base_export.h" 13 #include "base/logging.h" 14 #include "base/win/event_trace_provider.h" 15 16 namespace base { 17 template <typename Type> 18 struct StaticMemorySingletonTraits; 19 } // namespace base 20 21 namespace logging { 22 23 // Event ID for the log messages we generate. 24 EXTERN_C BASE_EXPORT const GUID kLogEventId; 25 26 // Feature enable mask for LogEventProvider. 27 enum LogEnableMask { 28 // If this bit is set in our provider enable mask, we will include 29 // a stack trace with every log message. 30 ENABLE_STACK_TRACE_CAPTURE = 0x0001, 31 // If this bit is set in our provider enable mask, the provider will log 32 // a LOG message with only the textual content of the message, and no 33 // stack trace. 34 ENABLE_LOG_MESSAGE_ONLY = 0x0002, 35 }; 36 37 // The message types our log event provider generates. 38 // ETW likes user message types to start at 10. 39 enum LogMessageTypes { 40 // A textual only log message, contains a zero-terminated string. 41 LOG_MESSAGE = 10, 42 // A message with a stack trace, followed by the zero-terminated 43 // message text. 44 LOG_MESSAGE_WITH_STACKTRACE = 11, 45 // A message with: 46 // a stack trace, 47 // the line number as a four byte integer, 48 // the file as a zero terminated UTF8 string, 49 // the zero-terminated UTF8 message text. 50 LOG_MESSAGE_FULL = 12, 51 }; 52 53 // Trace provider class to drive log control and transport 54 // with Event Tracing for Windows. 55 class BASE_EXPORT LogEventProvider : public base::win::EtwTraceProvider { 56 public: 57 LogEventProvider(const LogEventProvider&) = delete; 58 LogEventProvider& operator=(const LogEventProvider&) = delete; 59 static LogEventProvider* GetInstance(); 60 61 static bool LogMessage(logging::LogSeverity severity, const char* file, 62 int line, size_t message_start, const std::string& str); 63 64 static void Initialize(const GUID& provider_name); 65 static void Uninitialize(); 66 67 protected: 68 // Overridden to manipulate the log level on ETW control callbacks. 69 void OnEventsEnabled() override; 70 void OnEventsDisabled() override; 71 72 private: 73 LogEventProvider(); 74 75 // The log severity prior to OnEventsEnabled, 76 // restored in OnEventsDisabled. 77 logging::LogSeverity old_log_level_; 78 79 friend struct base::StaticMemorySingletonTraits<LogEventProvider>; 80 }; 81 82 } // namespace logging 83 84 #endif // BASE_LOGGING_WIN_H_ 85