Allow TimelineAnalysis to work on any TimelineEventRecorder

runtime/vm/timeline.h

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_TIMELINE_H_
 #define VM_TIMELINE_H_
 
 #include "vm/allocation.h"
 #include "vm/bitfield.h"
 
@@ skipping 330 matching lines @@
 
 // Recorder of |TimelineEvent|s.
 class TimelineEventRecorder {
  public:
   TimelineEventRecorder();
   virtual ~TimelineEventRecorder() {}
 
   // Interface method(s) which must be implemented.
   virtual void PrintJSON(JSONStream* js) = 0;
   virtual TimelineEventBlock* GetNewBlock() = 0;
+  virtual TimelineEventBlock* GetHeadBlock() = 0;
 
   void WriteTo(const char* directory);
 
  protected:
   // Interface method(s) which must be implemented.
   virtual void VisitObjectPointers(ObjectPointerVisitor* visitor) = 0;
   virtual TimelineEvent* StartEvent(const Object& object) = 0;
   virtual TimelineEvent* StartEvent() = 0;
   virtual void CompleteEvent(TimelineEvent* event) = 0;
 
   // Utility method(s).
   void PrintJSONMeta(JSONArray* array) const;
   TimelineEvent* ThreadBlockStartEvent();
 
+  Mutex lock_;
+
+  friend class TimelineEventBlockIterator;
   friend class TimelineStream;
   friend class Isolate;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(TimelineEventRecorder);
 };
 
 
 // A recorder that stores events in a ring buffer of fixed capacity.
 // This recorder does track Dart objects.
 class TimelineEventRingRecorder : public TimelineEventRecorder {
  public:
   static const intptr_t kDefaultCapacity = 8192;
 
   explicit TimelineEventRingRecorder(intptr_t capacity = kDefaultCapacity);
   ~TimelineEventRingRecorder();
 
   void PrintJSON(JSONStream* js);
   TimelineEventBlock* GetNewBlock();
+  TimelineEventBlock* GetHeadBlock();
 
  protected:
   void VisitObjectPointers(ObjectPointerVisitor* visitor);
   TimelineEvent* StartEvent(const Object& object);
   TimelineEvent* StartEvent();
   void CompleteEvent(TimelineEvent* event);
 
   TimelineEventBlock* GetNewBlockLocked();
 
   void PrintJSONEvents(JSONArray* array) const;
 
   TimelineEventBlock** blocks_;
   RawArray* event_objects_;
   intptr_t capacity_;
   intptr_t num_blocks_;
   intptr_t block_cursor_;
-  Mutex lock_;
 };
 
 
 // An abstract recorder that calls |StreamEvent| whenever an event is complete.
 // This recorder does not track Dart objects.
 class TimelineEventStreamingRecorder : public TimelineEventRecorder {
  public:
   TimelineEventStreamingRecorder();
   ~TimelineEventStreamingRecorder();
 
   void PrintJSON(JSONStream* js);
-  virtual TimelineEventBlock* GetNewBlock() {
+  TimelineEventBlock* GetNewBlock() {
+    return NULL;
+  }
+  TimelineEventBlock* GetHeadBlock() {
     return NULL;
   }
 
   // Called when |event| is ready to be streamed. It is unsafe to keep a
   // reference to |event| as it may be freed as soon as this function returns.
   virtual void StreamEvent(TimelineEvent* event) = 0;
 
  protected:
   void VisitObjectPointers(ObjectPointerVisitor* visitor);
   TimelineEvent* StartEvent(const Object& object);
   TimelineEvent* StartEvent();
   void CompleteEvent(TimelineEvent* event);
 };
 
 
 // A recorder that stores events in chains of blocks of events.
 // This recorder does not track Dart objects.
 // NOTE: This recorder will continue to allocate blocks until it exhausts
 // memory.
 class TimelineEventEndlessRecorder : public TimelineEventRecorder {
  public:
   TimelineEventEndlessRecorder();
 
   // Acquire a new block of events.
   // Takes a lock.
   // Recorder owns the block and it should be filled by only one thread.
   TimelineEventBlock* GetNewBlock();
 
+  TimelineEventBlock* GetHeadBlock();
+
   // It is expected that this function is only called when an isolate is
   // shutting itself down.
   // NOTE: Calling this while threads are filling in their blocks is not safe
   // and there are no checks in place to ensure that doesn't happen.
   // TODO(koda): Add isolate count to |ThreadRegistry| and verify that it is 1.
   void PrintJSON(JSONStream* js);
 
  protected:
   void VisitObjectPointers(ObjectPointerVisitor* visitor);
   TimelineEvent* StartEvent(const Object& object);
   TimelineEvent* StartEvent();
   void CompleteEvent(TimelineEvent* event);
 
   TimelineEventBlock* GetNewBlockLocked();
   void PrintJSONEvents(JSONArray* array) const;
 
-  Mutex lock_;
   TimelineEventBlock* head_;
   intptr_t block_index_;
-
-  friend class TimelineEventBlockIterator;
 };
 
 
 // An iterator for blocks.
 class TimelineEventBlockIterator {
  public:
-  explicit TimelineEventBlockIterator(TimelineEventEndlessRecorder* recorder);
+  explicit TimelineEventBlockIterator(TimelineEventRecorder* recorder);
   ~TimelineEventBlockIterator();
 
   void Reset();
   bool Next();
 
   TimelineEventBlock* current() const {
     return current_;
   }
 
  private:
   TimelineEventBlock* current_;
-  TimelineEventEndlessRecorder* recorder_;
+  TimelineEventRecorder* recorder_;
 };
 
 }  // namespace dart
 
 #endif  // VM_TIMELINE_H_