logging_win.h revision c7f5f8508d98d5952d42ed7648c2a8f30a4da156 
1// Copyright (c) 2009 The Chromium Authors. All rights reserved.
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 <string>
9#include "base/basictypes.h"
10#include "base/event_trace_provider_win.h"
11#include "base/logging.h"
12
13namespace logging {
14
15// Event ID for the log messages we generate.
16extern const GUID kLogEventId;
17
18// Feature enable mask for LogEventProvider.
19enum LogEnableMask {
20  // If this bit is set in our provider enable mask, we will include
21  // a stack trace with every log message.
22  ENABLE_STACK_TRACE_CAPTURE = 0x0001,
23};
24
25// The message types our log event provider generates.
26// ETW likes user message types to start at 10.
27enum LogMessageTypes {
28  // A textual only log message, contains a zero-terminated string.
29  LOG_MESSAGE = 10,
30  // A message with a stack trace, followed by the zero-terminated
31  // message text.
32  LOG_MESSAGE_WITH_STACKTRACE = 11,
33};
34
35// Trace provider class to drive log control and transport
36// with Event Tracing for Windows.
37class LogEventProvider : public EtwTraceProvider {
38 public:
39  LogEventProvider();
40
41  static bool LogMessage(int severity, const std::string& message);
42  static void Initialize(const GUID& provider_name);
43  static void Uninitialize();
44
45 protected:
46  // Overridden to manipulate the log level on ETW control callbacks.
47  virtual void OnEventsEnabled();
48  virtual void OnEventsDisabled();
49
50 private:
51  // The log severity prior to OnEventsEnabled,
52  // restored in OnEventsDisabled.
53  logging::LogSeverity old_log_level_;
54
55  DISALLOW_COPY_AND_ASSIGN(LogEventProvider);
56};
57
58}  // namespace logging
59
60#endif  // BASE_LOGGING_WIN_H_
61