arc: enable Android tracing in verified-boot mode

components/arc/trace/arc_trace_bridge.cc

Index: components/arc/trace/arc_trace_bridge.cc
diff --git a/components/arc/trace/arc_trace_bridge.cc b/components/arc/trace/arc_trace_bridge.cc
new file mode 100644
index 0000000000000000000000000000000000000000..3ed7f8e957bf5d19eb6fd9907af4e96fae0a2599
--- /dev/null
+++ b/components/arc/trace/arc_trace_bridge.cc
@@ -0,0 +1,107 @@
+// Copyright 2016 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 "components/arc/trace/arc_trace_bridge.h"
+
+#include <string>

[Yusuke Sato, 2016/10/12 05:58:13]

remove.

https://google.github.io/styleguide/cppguide.html#Names_and_Order_of_Includes

"However, any includes present in the related header do not need to be included
again in the related cc (i.e., foo.cc can rely on foo.h's includes)."

[shunhsingou, 2016/12/22 04:04:35]

Done.

+#include <utility>
+
+#include "base/logging.h"
+#include "base/trace_event/trace_event.h"

[Yusuke Sato, 2016/10/12 05:58:13]

remove

[shunhsingou, 2016/12/22 04:04:34]

Done.

+#include "components/arc/arc_bridge_service.h"
+
+namespace arc {
+
+namespace {

[Yusuke Sato, 2016/10/12 05:58:13]

space between line 16 and 17.

[shunhsingou, 2016/12/22 04:04:35]

Done.

+// This class is owned by ArcServiceManager so that it is safe to use this raw
+// pointer as the singleton reference.
+ArcTraceBridge* g_arc_trace_bridge = nullptr;
+
+// The prefix of the categories to be shown on the trace selection UI.
+constexpr char kCategoryPrefix[] = TRACE_DISABLED_BY_DEFAULT("android ");
+
+}  // namcespace
+
+ArcTraceBridge* ArcTraceBridge::Get() {
+  DCHECK(g_arc_trace_bridge);

[Yusuke Sato, 2016/10/12 05:58:13]

Does this make sense? Your c/b/chromeos/ code has null-checks. remove?

[shunhsingou, 2016/12/22 04:04:35]

Done.

+  return g_arc_trace_bridge;
+}
+
+ArcTraceBridge::ArcTraceBridge(ArcBridgeService* bridge_service)
+    : ArcService(bridge_service), binding_(this), weak_ptr_factory_(this) {
+  arc_bridge_service()->trace()->AddObserver(this);
+  g_arc_trace_bridge = this;
+}
+
+ArcTraceBridge::~ArcTraceBridge() {
+  arc_bridge_service()->trace()->RemoveObserver(this);
+  g_arc_trace_bridge = nullptr;
+}
+
+void ArcTraceBridge::OnInstanceReady() {
+  QueryAvailableCategories();
+}
+
+void ArcTraceBridge::QueryAvailableCategories() {
+  auto* trace_instance = arc_bridge_service()->trace()->GetInstanceForMethod(
+      "QueryAvailableCategories");
+  if (!trace_instance)
+    return;
+  trace_instance->QueryAvailableCategories(base::Bind(
+      &ArcTraceBridge::OnCategoriesReady, weak_ptr_factory_.GetWeakPtr()));
+}
+
+void ArcTraceBridge::OnCategoriesReady(mojo::Array<mojo::String> categories) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  for (const auto& category : categories) {
+    categories_.push_back(Category(
+        category, std::string(kCategoryPrefix) + std::string(category)));

[Yusuke Sato, 2016/10/12 05:58:13]

Converting both to std::string seems redundant.

 kCategoryPrefix + category.get()

or something alike?

[shunhsingou, 2016/12/22 04:04:34]

Done.

+    // Shows the category name in the selection UI.

[Yusuke Sato, 2016/10/12 05:58:13]

nit: Show (imperative form)

[shunhsingou, 2016/12/22 04:04:35]

Done.

+    base::trace_event::TraceLog::GetCategoryGroupEnabled(
+        categories_.back().full_name.c_str());
+  }
+}
+
+void ArcTraceBridge::StartTracing(
+    const base::trace_event::TraceConfig& trace_config) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  auto* trace_instance =
+      arc_bridge_service()->trace()->GetInstanceForMethod("StartTracing");
+  if (!trace_instance)
+    return;
+
+  mojo::Array<mojo::String> selected_categories;
+  for (const auto& category : categories_) {
+    if (trace_config.IsCategoryGroupEnabled(category.full_name.c_str())) {

[Yusuke Sato, 2016/10/12 05:58:13]

nit: no {} for one-line if.

[shunhsingou, 2016/12/22 04:04:35]

Done.

+      selected_categories.push_back(category.name);
+    }
+  }
+
+  trace_instance->StartTracing(std::move(selected_categories),
+                               base::Bind(&ArcTraceBridge::OnTraceStart,
+                                          weak_ptr_factory_.GetWeakPtr()));
+}
+
+void ArcTraceBridge::StopTracing() {
+  auto* trace_instance =
+      arc_bridge_service()->trace()->GetInstanceForMethod("StopTracing");
+  if (!trace_instance)
+    return;
+  trace_instance->StopTracing(
+      base::Bind(&ArcTraceBridge::OnTraceStop, weak_ptr_factory_.GetWeakPtr()));
+}
+
+void ArcTraceBridge::OnTraceStart(bool success) {
+  if (!success)
+    LOG(ERROR) << "Failed to start tracing in the container.";
+}
+
+void ArcTraceBridge::OnTraceStop(bool success) {
+  if (!success)
+    LOG(ERROR) << "Failed to stop tracing in the container.";
+}
+
+}  // namespace arc