Make Tracing Service not use outgoing InterfaceProvider, update conventions

services/tracing/public/cpp/trace_provider_impl.cc

-// Copyright 2015 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 "services/tracing/public/cpp/trace_provider_impl.h"
-
-#include <utility>
-
-#include "base/callback.h"
-#include "base/logging.h"
-#include "base/memory/weak_ptr.h"
-#include "base/single_thread_task_runner.h"
-#include "base/time/time.h"
-#include "base/trace_event/trace_config.h"
-#include "base/trace_event/trace_event.h"
-#include "services/shell/public/cpp/connection.h"
-
-namespace mojo {
-
-TraceProviderImpl::TraceProviderImpl()
-    : binding_(this), tracing_forced_(false), weak_factory_(this) {}
-
-TraceProviderImpl::~TraceProviderImpl() {
-  StopTracing();
-}
-
-void TraceProviderImpl::Bind(InterfaceRequest<tracing::TraceProvider> request) {
-  if (!binding_.is_bound()) {
-    binding_.Bind(std::move(request));
-  } else {
-    LOG(ERROR) << "Cannot accept two connections to TraceProvider.";
-  }
-}
-
-void TraceProviderImpl::StartTracing(const String& categories,
-                                     tracing::TraceRecorderPtr recorder) {
-  DCHECK(!recorder_);
-  recorder_ = std::move(recorder);
-  tracing_forced_ = false;
-  if (!base::trace_event::TraceLog::GetInstance()->IsEnabled()) {
-    std::string categories_str = categories.To<std::string>();
-    base::trace_event::TraceLog::GetInstance()->SetEnabled(
-        base::trace_event::TraceConfig(categories_str,
-                                       base::trace_event::RECORD_UNTIL_FULL),
-        base::trace_event::TraceLog::RECORDING_MODE);
-  }
-}
-
-void TraceProviderImpl::StopTracing() {
-  if (recorder_) {
-    base::trace_event::TraceLog::GetInstance()->SetDisabled();
-
-    base::trace_event::TraceLog::GetInstance()->Flush(
-        base::Bind(&TraceProviderImpl::SendChunk, base::Unretained(this)));
-  }
-}
-
-void TraceProviderImpl::ForceEnableTracing() {
-  base::trace_event::TraceLog::GetInstance()->SetEnabled(
-      base::trace_event::TraceConfig("*", base::trace_event::RECORD_UNTIL_FULL),
-      base::trace_event::TraceLog::RECORDING_MODE);
-  tracing_forced_ = true;
-  base::MessageLoop::current()->task_runner()->PostTask(
-      FROM_HERE,
-      base::Bind(&TraceProviderImpl::DelayedStop, weak_factory_.GetWeakPtr()));
-}
-
-void TraceProviderImpl::DelayedStop() {
-  // We use this indirection to account for cases where the Initialize app
-  // method (within which TraceProviderImpl is created) takes more than one
-  // second to finish; thus we start the countdown only when the current thread
-  // is unblocked.
-  base::MessageLoop::current()->task_runner()->PostDelayedTask(
-      FROM_HERE,
-      base::Bind(&TraceProviderImpl::StopIfForced, weak_factory_.GetWeakPtr()),
-      base::TimeDelta::FromSeconds(1));
-}
-
-void TraceProviderImpl::StopIfForced() {
-  if (!tracing_forced_) {
-    return;
-  }
-  base::trace_event::TraceLog::GetInstance()->SetDisabled();
-  base::trace_event::TraceLog::GetInstance()->Flush(
-      base::Callback<void(const scoped_refptr<base::RefCountedString>&,
-                          bool)>());
-}
-
-void TraceProviderImpl::SendChunk(
-    const scoped_refptr<base::RefCountedString>& events_str,
-    bool has_more_events) {
-  DCHECK(recorder_);
-  // The string will be empty if an error eccured or there were no trace
-  // events. Empty string is not a valid chunk to record so skip in this case.
-  if (!events_str->data().empty()) {
-    recorder_->Record(mojo::String(events_str->data()));
-  }
-  if (!has_more_events) {
-    recorder_.reset();
-  }
-}
-
-}  // namespace mojo