Keep only base/extractor.[cc|h].

base/etw_log_writer.h

-// Copyright 2010 Google Inc.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-// ========================================================================
-//
-// A log writer that is controlled, and outputs to Event Tracing for Windows.
-
-#ifndef OMAHA_BASE_ETW_LOG_WRITER_H_
-#define OMAHA_BASE_ETW_LOG_WRITER_H_
-
-#include "omaha/base/event_trace_provider.h"
-#include "omaha/base/logging.h"
-
-namespace omaha {
-
-class EtwLogWriter : public LogWriter, public EtwTraceProvider {
- public:
-  // The Omaha trace provider's GUID.
-  static const GUID kOmahaTraceGuid;
-
-  // The event ID for the event types below.
-  static const GUID kLogEventId;
-
-  // The event type for a simple UTF-8 zero-terminated message event.
-  static const EtwEventType kLogMessageType = 10;
-
-  // The event type for a log message with a stack trace, followed by the
-  // zero-terminated UTF-8 message text.
-  static const EtwEventType kLogMessageWithStackTraceType = 11;
-
-  // The lowest-order enable flags bit turn on stack trace capture.
-  // The remaining enable bits correspond to log categories, starting
-  // from LC_LOGGING through LC_MAX_CAT - 1.
-  static const EtwEventFlags kCaptureStackTraceMask = 0x0001;
-
-  // LogWriter overrides.
-  virtual bool WantsToLogRegardless() const;
-  virtual bool IsCatLevelEnabled(LogCategory category, LogLevel level) const;
-  virtual void OutputMessage(const OutputInfo* output_info);
-
-  // Factory for new instances.
-  static EtwLogWriter* Create();
-
-  // Convert a log category to the corresponding ETW enable flag.
-  static EtwEventFlags CategoryToEnableFlag(LogCategory category);
-
-  // Convert from a log level to the corresponding ETW trace level.
-  static EtwEventLevel LogLevelToTraceLevel(LogLevel level);
-
- protected:
-  explicit EtwLogWriter(const GUID& provider_guid);
-  virtual void Cleanup();
-
-  // Override from EtwTraceProvider.
-  virtual void OnEventsEnabled();
-  virtual void OnEventsDisabled();
-
- private:
-  // The CaptureStackBackTrace function is only available as of Windows XP,
-  // and is only declared in SDK headers as of the Vista SDK. To uncomplicate
-  // things we get at the function through GetProcAddress.
-  typedef WORD (NTAPI* RtlCaptureStackBackTraceFunc)(DWORD frames_to_skip,
-                                                     DWORD frames_to_capture,
-                                                     PVOID* backtrace,
-                                                     PDWORD backtrace_hash);
-
-  RtlCaptureStackBackTraceFunc rtl_capture_stack_backtrace_;
-
-  DISALLOW_COPY_AND_ASSIGN(EtwLogWriter);
-};
-
-}  // namespace omaha
-
-#endif  // OMAHA_BASE_ETW_LOG_WRITER_H_