WIP: The tracing service prototype

content/browser/tracing/tracing_controller_impl.h

 // Copyright (c) 2013 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.
 
 #ifndef CONTENT_BROWSER_TRACING_TRACING_CONTROLLER_IMPL_H_
 #define CONTENT_BROWSER_TRACING_TRACING_CONTROLLER_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <list>
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/lazy_instance.h"
 #include "base/macros.h"
 #include "base/time/time.h"
 #include "base/trace_event/memory_dump_manager.h"
 #include "base/trace_event/tracing_agent.h"
 #include "content/public/browser/tracing_controller.h"
+#include "mojo/common/data_pipe_drainer.h"
+#include "services/resource_coordinator/public/interfaces/tracing/tracing.mojom.h"
+#include "services/service_manager/public/cpp/connector.h"
 
 namespace base {
 class RefCountedString;
 }
 
 namespace content {
 
 class TraceMessageFilter;
 class TracingUI;
 
 // An implementation of this interface is passed when constructing a
 // TraceDataSink, and receives chunks of the final trace data as it's being
 // constructed.
 // Methods may be called from any thread.
 class CONTENT_EXPORT TraceDataEndpoint
     : public base::RefCountedThreadSafe<TraceDataEndpoint> {
  public:
   virtual void ReceiveTraceChunk(std::unique_ptr<std::string> chunk) {}
   virtual void ReceiveTraceFinalContents(
       std::unique_ptr<const base::DictionaryValue> metadata) {}
 
  protected:
   friend class base::RefCountedThreadSafe<TraceDataEndpoint>;
   virtual ~TraceDataEndpoint() {}
 };
 
-class TracingControllerImpl
-    : public TracingController,
-      public base::trace_event::TracingAgent {
+class TracingControllerImpl : public TracingController,
+                              public mojo::common::DataPipeDrainer::Client {
  public:
   // Create an endpoint that may be supplied to any TraceDataSink to
   // dump the trace data to a callback.
   CONTENT_EXPORT static scoped_refptr<TraceDataEndpoint> CreateCallbackEndpoint(
       const base::Callback<void(std::unique_ptr<const base::DictionaryValue>,
                                 base::RefCountedString*)>& callback);
 
   CONTENT_EXPORT static scoped_refptr<TraceDataSink> CreateCompressedStringSink(
       scoped_refptr<TraceDataEndpoint> endpoint);
   static scoped_refptr<TraceDataSink> CreateJSONSink(
       scoped_refptr<TraceDataEndpoint> endpoint);
 
   static TracingControllerImpl* GetInstance();
 
+  void Initialize(service_manager::Connector* connector);
+
   // TracingController implementation.
   bool GetCategories(const GetCategoriesDoneCallback& callback) override;
   bool StartTracing(const base::trace_event::TraceConfig& trace_config,
                     const StartTracingDoneCallback& callback) override;
   bool StopTracing(const scoped_refptr<TraceDataSink>& sink) override;
   bool GetTraceBufferUsage(
       const GetTraceBufferUsageCallback& callback) override;
   void AddMetadata(const base::DictionaryValue& metadata) override;
 
   bool IsTracing() const override;
 
   void RegisterTracingUI(TracingUI* tracing_ui);
   void UnregisterTracingUI(TracingUI* tracing_ui);
 
-  // base::trace_event::TracingAgent implementation.
-  std::string GetTracingAgentName() override;
-  std::string GetTraceEventLabel() override;
-  void StartAgentTracing(const base::trace_event::TraceConfig& trace_config,
-                         const StartAgentTracingCallback& callback) override;
-  void StopAgentTracing(const StopAgentTracingCallback& callback) override;
-  bool SupportsExplicitClockSync() override;
-  void RecordClockSyncMarker(
-      const std::string& sync_id,
-      const RecordClockSyncMarkerCallback& callback) override;
-
   class TraceMessageFilterObserver {
    public:
     virtual void OnTraceMessageFilterAdded(TraceMessageFilter* filter) = 0;
     virtual void OnTraceMessageFilterRemoved(TraceMessageFilter* filter) = 0;
   };
   void AddTraceMessageFilterObserver(TraceMessageFilterObserver* observer);
   void RemoveTraceMessageFilterObserver(TraceMessageFilterObserver* observer);
 
  private:
   friend struct base::LazyInstanceTraitsBase<TracingControllerImpl>;
   friend class TraceMessageFilter;
 
   TracingControllerImpl();
   ~TracingControllerImpl() override;
 
-  bool can_start_tracing() const { return !enabled_tracing_modes_; }
-
-  bool can_stop_tracing() const {
-    return enabled_tracing_modes_ && !trace_data_sink_.get();
-  }
-
-  bool can_start_monitoring() const {
-    return !is_monitoring_;
-  }
-
-  bool can_stop_monitoring() const {
-    return is_monitoring_ && !monitoring_data_sink_.get();
-  }
-
-  bool can_get_trace_buffer_usage() const {
-    return pending_trace_buffer_usage_callback_.is_null();
-  }
-
   // Methods for use by TraceMessageFilter.
   void AddTraceMessageFilter(TraceMessageFilter* trace_message_filter);
   void RemoveTraceMessageFilter(TraceMessageFilter* trace_message_filter);
 
-  void OnTraceDataCollected(
-      const scoped_refptr<base::RefCountedString>& events_str_ptr);
-
-  // Callback of TraceLog::Flush() for the local trace.
-  void OnLocalTraceDataCollected(
-      const scoped_refptr<base::RefCountedString>& events_str_ptr,
-      bool has_more_events);
-
-  // Adds the tracing agent with the specified agent name to the list of
-  // additional tracing agents.
-  void AddTracingAgent(const std::string& agent_name);
-
-  void OnStartAgentTracingAcked(const std::string& agent_name, bool success);
-
-  void OnStopTracingAcked(
-      TraceMessageFilter* trace_message_filter,
-      const std::vector<std::string>& known_category_groups);
-
-  void OnEndAgentTracingAcked(
-      const std::string& agent_name,
-      const std::string& events_label,
-      const scoped_refptr<base::RefCountedString>& events_str_ptr);
-
-  void OnTraceLogStatusReply(TraceMessageFilter* trace_message_filter,
-                             const base::trace_event::TraceLogStatus& status);
-
-  void SetEnabledOnFileThread(
-      const base::trace_event::TraceConfig& trace_config,
-      const base::Closure& callback);
-  void SetDisabledOnFileThread(const base::Closure& callback);
-  void OnAllTracingAgentsStarted();
-  void StopTracingAfterClockSync();
-  void OnStopTracingDone();
-
-  // Issue clock sync markers to the tracing agents.
-  void IssueClockSyncMarker();
-  void OnClockSyncMarkerRecordedByAgent(
-      const std::string& sync_id,
-      const base::TimeTicks& issue_ts,
-      const base::TimeTicks& issue_end_ts);
-
   void AddFilteredMetadata(TracingController::TraceDataSink* sink,
                            std::unique_ptr<base::DictionaryValue> metadata,
                            const MetadataFilterPredicate& filter);
 
-  std::unique_ptr<base::DictionaryValue> GenerateTracingMetadataDict() const;
+  void GetCategoriesDone(const GetCategoriesDoneCallback& callback,
+                         const std::string& categories);
+  void GetTraceBufferUsageDone(const GetTraceBufferUsageCallback& callback,
+                               bool success,
+                               float percent_full,
+                               uint32_t approximate_count);
+
+  // mojo::common::DataPipeDrainer::Client
+  void OnDataAvailable(const void* data, size_t num_bytes) override;
+  void OnDataComplete() override;
 
   typedef std::set<scoped_refptr<TraceMessageFilter>> TraceMessageFilterSet;
   TraceMessageFilterSet trace_message_filters_;
 
-  // Pending acks for StartTracing.
-  int pending_start_tracing_ack_count_;
-  base::OneShotTimer start_tracing_timer_;
-  StartTracingDoneCallback start_tracing_done_callback_;
-  std::unique_ptr<base::trace_event::TraceConfig> trace_config_;
-
-  // Pending acks for StopTracing.
-  int pending_stop_tracing_ack_count_;
-  TraceMessageFilterSet pending_stop_tracing_filters_;
-
-  // Pending acks for GetTraceLogStatus.
-  int pending_trace_log_status_ack_count_;
-  TraceMessageFilterSet pending_trace_log_status_filters_;
-  float maximum_trace_buffer_usage_;
-  size_t approximate_event_count_;
-
-  std::vector<base::trace_event::TracingAgent*> additional_tracing_agents_;
-  int pending_clock_sync_ack_count_;
-  base::OneShotTimer clock_sync_timer_;
-
-  uint8_t enabled_tracing_modes_;
-  bool is_monitoring_;
-
-  GetCategoriesDoneCallback pending_get_categories_done_callback_;
-  GetTraceBufferUsageCallback pending_trace_buffer_usage_callback_;
-
   base::ObserverList<TraceMessageFilterObserver>
       trace_message_filter_observers_;
 
-  std::set<std::string> known_category_groups_;
   std::set<TracingUI*> tracing_uis_;
   scoped_refptr<TraceDataSink> trace_data_sink_;
   scoped_refptr<TraceDataSink> monitoring_data_sink_;
   std::unique_ptr<base::DictionaryValue> metadata_;
+  bool is_tracing_ = false;
+
+  resource_coordinator::tracing::mojom::CoordinatorPtr coordinator_;
+  std::unique_ptr<mojo::common::DataPipeDrainer> drainer_;
 
   DISALLOW_COPY_AND_ASSIGN(TracingControllerImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_TRACING_TRACING_CONTROLLER_IMPL_H_