logging_win.cc 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#include "base/logging_win.h"
6#include "base/atomicops.h"
7#include "base/singleton.h"
8#include <initguid.h>  // NOLINT
9
10namespace {
11
12struct LogEventProviderTraits {
13  // WARNING: User has to deal with get() returning NULL.
14  static logging::LogEventProvider* New() {
15    if (base::subtle::NoBarrier_AtomicExchange(&dead_, 1))
16      return NULL;
17    logging::LogEventProvider* ptr =
18        reinterpret_cast<logging::LogEventProvider*>(buffer_);
19    // We are protected by a memory barrier.
20    new(ptr) logging::LogEventProvider();
21    return ptr;
22  }
23
24  static void Delete(logging::LogEventProvider* p) {
25    base::subtle::NoBarrier_Store(&dead_, 1);
26    MemoryBarrier();
27    p->logging::LogEventProvider::~LogEventProvider();
28  }
29
30  static const bool kRegisterAtExit = true;
31
32 private:
33  static const size_t kBufferSize = (sizeof(logging::LogEventProvider) +
34                                     sizeof(intptr_t) - 1) / sizeof(intptr_t);
35  static intptr_t buffer_[kBufferSize];
36
37  // Signal the object was already deleted, so it is not revived.
38  static base::subtle::Atomic32 dead_;
39};
40
41intptr_t LogEventProviderTraits::buffer_[kBufferSize];
42base::subtle::Atomic32 LogEventProviderTraits::dead_ = 0;
43
44Singleton<logging::LogEventProvider, LogEventProviderTraits> log_provider;
45
46}  // namespace
47
48namespace logging {
49
50DEFINE_GUID(kLogEventId,
51    0x7fe69228, 0x633e, 0x4f06, 0x80, 0xc1, 0x52, 0x7f, 0xea, 0x23, 0xe3, 0xa7);
52
53LogEventProvider::LogEventProvider() : old_log_level_(LOG_NONE) {
54}
55
56bool LogEventProvider::LogMessage(int severity, const std::string& message) {
57  EtwEventLevel level = TRACE_LEVEL_NONE;
58
59  // Convert the log severity to the most appropriate ETW trace level.
60  switch (severity) {
61    case LOG_INFO:
62      level = TRACE_LEVEL_INFORMATION;
63      break;
64    case LOG_WARNING:
65      level = TRACE_LEVEL_WARNING;
66      break;
67    case LOG_ERROR:
68    case LOG_ERROR_REPORT:
69      level = TRACE_LEVEL_ERROR;
70      break;
71    case LOG_FATAL:
72      level = TRACE_LEVEL_FATAL;
73      break;
74  };
75
76  // Bail if we're not logging, not at that level,
77  // or if we're post-atexit handling.
78  LogEventProvider* provider = log_provider.get();
79  if (provider == NULL || level > provider->enable_level())
80    return false;
81
82  // And now log the event, with stack trace if one is
83  // requested per our enable flags.
84  if (provider->enable_flags() & ENABLE_STACK_TRACE_CAPTURE) {
85    const size_t kMaxBacktraceDepth = 32;
86    void* backtrace[kMaxBacktraceDepth];
87    DWORD depth = CaptureStackBackTrace(2, kMaxBacktraceDepth, backtrace, NULL);
88    EtwMofEvent<3> event(kLogEventId, LOG_MESSAGE_WITH_STACKTRACE, level);
89
90    event.SetField(0, sizeof(depth), &depth);
91    event.SetField(1, sizeof(backtrace[0]) * depth, &backtrace);
92    event.SetField(2, message.length() + 1, message.c_str());
93
94    provider->Log(event.get());
95  } else {
96    EtwMofEvent<1> event(kLogEventId, LOG_MESSAGE, level);
97    event.SetField(0, message.length() + 1, message.c_str());
98    provider->Log(event.get());
99  }
100
101  // Don't increase verbosity in other log destinations.
102  if (severity >= provider->old_log_level_)
103    return true;
104
105  return false;
106}
107
108void LogEventProvider::Initialize(const GUID& provider_name) {
109  LogEventProvider* provider = log_provider.get();
110
111  provider->set_provider_name(provider_name);
112  provider->Register();
113
114  // Register our message handler with logging.
115  SetLogMessageHandler(LogMessage);
116}
117
118void LogEventProvider::Uninitialize() {
119  log_provider.get()->Unregister();
120}
121
122void LogEventProvider::OnEventsEnabled() {
123  // Grab the old log level so we can restore it later.
124  old_log_level_ = GetMinLogLevel();
125
126  // Convert the new trace level to a logging severity
127  // and enable logging at that level.
128  EtwEventLevel level = enable_level();
129  switch (level) {
130    case TRACE_LEVEL_NONE:
131    case TRACE_LEVEL_FATAL:
132      SetMinLogLevel(LOG_FATAL);
133      break;
134    case TRACE_LEVEL_ERROR:
135      SetMinLogLevel(LOG_ERROR);
136      break;
137    case TRACE_LEVEL_WARNING:
138      SetMinLogLevel(LOG_WARNING);
139      break;
140    case TRACE_LEVEL_INFORMATION:
141    case TRACE_LEVEL_VERBOSE:
142      SetMinLogLevel(LOG_INFO);
143      break;
144  }
145}
146
147void LogEventProvider::OnEventsDisabled() {
148  // Restore the old log level.
149  SetMinLogLevel(old_log_level_);
150}
151
152}  // namespace logging
153