base/files/file_tracing.cc

   1 // Copyright 2015 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/files/file_tracing.h"
   6
   7 #include "base/files/file.h"
   8
   9 namespace base {
  10
  11 namespace {
  12 FileTracing::Provider* g_provider = nullptr;
  13 }
  14
  15 // static
  16 void FileTracing::SetProvider(FileTracing::Provider* provider) {
  17   g_provider = provider;
  18 }
  19
  20 FileTracing::ScopedEnabler::ScopedEnabler() {
  21   if (g_provider)
  22     g_provider->FileTracingEnable(this);
  23 }
  24
  25 FileTracing::ScopedEnabler::~ScopedEnabler() {
  26   if (g_provider)
  27     g_provider->FileTracingDisable(this);
  28 }
  29
  30 FileTracing::ScopedTrace::ScopedTrace() : id_(nullptr) {}
  31
  32 FileTracing::ScopedTrace::~ScopedTrace() {
  33   if (id_ && g_provider)
  34     g_provider->FileTracingEventEnd(name_, id_);
  35 }
  36
  37 bool FileTracing::ScopedTrace::ShouldInitialize() const {
  38   return g_provider && g_provider->FileTracingCategoryIsEnabled();
  39 }
  40
  41 void FileTracing::ScopedTrace::Initialize(
  42     const char* name, File* file, int64 size) {
  43   if (!g_provider)
  44     return;
  45
  46   id_ = &file->trace_enabler_;
  47   name_ = name;
  48
  49   g_provider->FileTracingEventBegin(name_, id_, file->path_, size);
  50 }
  51
  52 }  // namespace base