1 files changed, 126 insertions, 0 deletions
diff --git a/base/event_trace_provider_win.cc b/base/event_trace_provider_win.cc
new file mode 100644
index 0000000..69fcd57
--- /dev/null
+++ b/base/event_trace_provider_win.cc
@@ -0,0 +1,126 @@
+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+#include "base/event_trace_provider_win.h"
+#include <windows.h>
+#include <cguid.h>
+
+TRACE_GUID_REGISTRATION EtwTraceProvider::obligatory_guid_registration_ = {
+  &GUID_NULL,
+  NULL
+};
+
+EtwTraceProvider::EtwTraceProvider(const GUID& provider_name)
+    : provider_name_(provider_name), registration_handle_(NULL),
+      session_handle_(NULL), enable_flags_(0), enable_level_(0) {
+}
+
+EtwTraceProvider::EtwTraceProvider()
+    : provider_name_(GUID_NULL), registration_handle_(NULL),
+      session_handle_(NULL), enable_flags_(0), enable_level_(0) {
+}
+
+EtwTraceProvider::~EtwTraceProvider() {
+  Unregister();
+}
+
+ULONG EtwTraceProvider::EnableEvents(void* buffer) {
+  session_handle_ = ::GetTraceLoggerHandle(buffer);
+  if (NULL == session_handle_) {
+    return ::GetLastError();
+  }
+
+  enable_flags_ = ::GetTraceEnableFlags(session_handle_);
+  enable_level_ = ::GetTraceEnableLevel(session_handle_);
+
+  // Give subclasses a chance to digest the state change.
+  OnEventsEnabled();
+
+  return ERROR_SUCCESS;
+}
+
+ULONG EtwTraceProvider::DisableEvents() {
+  enable_level_ = 0;
+  enable_flags_ = 0;
+  session_handle_ = NULL;
+
+  // Give subclasses a chance to digest the state change.
+  OnEventsDisabled();
+
+  return ERROR_SUCCESS;
+}
+
+ULONG EtwTraceProvider::Callback(WMIDPREQUESTCODE request, void* buffer) {
+  switch (request) {
+    case WMI_ENABLE_EVENTS:
+      return EnableEvents(buffer);
+    case WMI_DISABLE_EVENTS:
+      return DisableEvents();
+    default:
+      return ERROR_INVALID_PARAMETER;
+  }
+  // Not reached.
+}
+
+ULONG WINAPI EtwTraceProvider::ControlCallback(WMIDPREQUESTCODE request,
+    void* context, ULONG *reserved, void* buffer) {
+  EtwTraceProvider *provider = reinterpret_cast<EtwTraceProvider*>(context);
+
+  return provider->Callback(request, buffer);
+}
+
+ULONG EtwTraceProvider::Register() {
+  if (provider_name_ == GUID_NULL)
+    return ERROR_INVALID_NAME;
+
+  return ::RegisterTraceGuids(ControlCallback, this, &provider_name_,
+      1, &obligatory_guid_registration_, NULL, NULL, &registration_handle_);
+}
+
+ULONG EtwTraceProvider::Unregister() {
+  ULONG ret = ::UnregisterTraceGuids(registration_handle_);
+
+  // Make sure we don't log anything from here on.
+  enable_level_ = 0;
+  enable_flags_ = 0;
+  session_handle_ = NULL;
+  registration_handle_ = NULL;
+
+  return ret;
+}
+
+ULONG EtwTraceProvider::Log(const EtwEventClass& event_class,
+    EtwEventType type, EtwEventLevel level, const char *message) {
+  if (NULL == session_handle_ || enable_level_ < level)
+    return ERROR_SUCCESS;  // No one listening.
+
+  EtwMofEvent<1> event(event_class, type, level);
+
+  event.fields[0].DataPtr = reinterpret_cast<ULONG64>(message);
+  event.fields[0].Length = message ?
+      sizeof(message[0]) * (1 + strlen(message)) : 0;
+
+  return ::TraceEvent(session_handle_, &event.header);
+}
+
+ULONG EtwTraceProvider::Log(const EtwEventClass& event_class,
+    EtwEventType type, EtwEventLevel level, const wchar_t *message) {
+  if (NULL == session_handle_ || enable_level_ < level)
+    return ERROR_SUCCESS;  // No one listening.
+
+  EtwMofEvent<1> event(event_class, type, level);
+
+  event.fields[0].DataPtr = reinterpret_cast<ULONG64>(message);
+  event.fields[0].Length = message ?
+      sizeof(message[0]) * (1 + wcslen(message)) : 0;
+
+  return ::TraceEvent(session_handle_, &event.header);
+}
+
+ULONG EtwTraceProvider::Log(EVENT_TRACE_HEADER* event) {
+  if (enable_level_ < event->Class.Level)
+    return ERROR_SUCCESS;
+
+  return ::TraceEvent(session_handle_, event);
+}