Add tracing service and make the shell+sky_viewer+services talk to it

services/tracing/main.cc

+// Copyright 2014 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/bind.h"
+#include "mojo/application/application_runner_chromium.h"
+#include "mojo/common/weak_binding_set.h"
+#include "mojo/public/c/system/main.h"
+#include "mojo/public/cpp/application/application_delegate.h"
+#include "mojo/public/cpp/application/application_impl.h"
+#include "services/tracing/trace_data_sink.h"
+#include "services/tracing/tracing.mojom.h"
+
+namespace tracing {
+
+class TracingApp : public mojo::ApplicationDelegate,
+                   public mojo::InterfaceFactory<TraceCoordinator>,
+                   public tracing::TraceCoordinator,
+                   public mojo::InterfaceFactory<TraceDataCollector>,
+                   public tracing::TraceDataCollector {
+ public:
+  TracingApp() {}
+  ~TracingApp() override {}
+
+ private:
+  // mojo::ApplicationDelegate implementation.
+  bool ConfigureIncomingConnection(
+      mojo::ApplicationConnection* connection) override {
+    connection->AddService<TraceCoordinator>(this);
+    connection->AddService<TraceDataCollector>(this);
+    return true;
+  }
+
+  // mojo::InterfaceFactory<TraceCoordinator> implementation.
+  void Create(mojo::ApplicationConnection* connection,
+              mojo::InterfaceRequest<TraceCoordinator> request) override {
+    coordinator_bindings_.AddBinding(this, request.Pass());
+  }
+
+  // mojo::InterfaceFactory<TraceDataCollector> implementation.
+  void Create(mojo::ApplicationConnection* connection,
+              mojo::InterfaceRequest<TraceDataCollector> request) override {
+    collector_bindings_.AddBinding(this, request.Pass());
+  }
+
+  // tracing::TraceCoordinator implementation.
+  void Start(const mojo::String& base_name,
+             const mojo::String& categories) override {
+    base::FilePath base_name_path =
+        base::FilePath::FromUTF8Unsafe(base_name.To<std::string>());
+    sink_.reset(new TraceDataSink(base_name_path));
+    collector_bindings_.ForAllBindings([categories](
+        TraceController* controller) { controller->StartTracing(categories); });
+  }
+  void StopAndFlush() override {
+    collector_bindings_.ForAllBindings(
+        [](TraceController* controller) { controller->StopTracing(); });
+
+    // TODO: We really should keep track of how many connections we have here
+    // and flush + reset the sink after we receive a EndTracing or a detect a
+    // pipe closure on all pipes.
+    base::MessageLoop::current()->PostDelayedTask(
+        FROM_HERE,
+        base::Bind(&TraceDataSink::Flush, base::Unretained(sink_.get())),
+        base::TimeDelta::FromSeconds(1));
+  }
+
+  // tracing::TraceDataCollector implementation.
+  void DataCollected(const mojo::String& json) override {
+    if (sink_)
+      sink_->AddChunk(json.To<std::string>());
+  }
+  // tracing::TraceDataCollector implementation.
+  void EndTracing() override {}
+
+  scoped_ptr<TraceDataSink> sink_;
+  mojo::WeakBindingSet<TraceDataCollector> collector_bindings_;
+  mojo::WeakBindingSet<TraceCoordinator> coordinator_bindings_;
+
+  DISALLOW_COPY_AND_ASSIGN(TracingApp);
+};
+
+}  // namespace tracing
+
+MojoResult MojoMain(MojoHandle shell_handle) {
+  mojo::ApplicationRunnerChromium runner(new tracing::TracingApp);
+  return runner.Run(shell_handle);
+}