[api,profiler] Introduce GetRetainerInfos callback for profiling

src/profiler/heap-profiler.cc

 // Copyright 2009-2010 the V8 project 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 "src/profiler/heap-profiler.h"
 
 #include "src/api.h"
 #include "src/debug/debug.h"
 #include "src/profiler/allocation-tracker.h"
 #include "src/profiler/heap-snapshot-generator-inl.h"
 #include "src/profiler/sampling-heap-profiler.h"
 
 namespace v8 {
 namespace internal {
 
 HeapProfiler::HeapProfiler(Heap* heap)
     : ids_(new HeapObjectsMap(heap)),
       names_(new StringsStorage(heap)),
-      is_tracking_object_moves_(false) {
-}
-
+      is_tracking_object_moves_(false),
+      get_retainer_infos_callback_(nullptr) {}
 
 static void DeleteHeapSnapshot(HeapSnapshot** snapshot_ptr) {
   delete *snapshot_ptr;
 }
 
 
 HeapProfiler::~HeapProfiler() {
   snapshots_.Iterate(DeleteHeapSnapshot);
   snapshots_.Clear();
 }
@@ skipping 22 matching lines @@
 }
 
 
 v8::RetainedObjectInfo* HeapProfiler::ExecuteWrapperClassCallback(
     uint16_t class_id, Object** wrapper) {
   if (wrapper_callbacks_.length() <= class_id) return NULL;
   return wrapper_callbacks_[class_id](
       class_id, Utils::ToLocal(Handle<Object>(wrapper)));
 }
 
+void HeapProfiler::SetGetRetainerInfosCallback(
+    v8::HeapProfiler::GetRetainerInfosCallback callback) {
+  get_retainer_infos_callback_ = callback;
+}
+
+v8::HeapProfiler::RetainerInfos HeapProfiler::GetRetainerInfos(
+    Isolate* isolate) {
+  v8::HeapProfiler::RetainerInfos infos;
+  if (get_retainer_infos_callback_ != nullptr)
+    infos =
+        get_retainer_infos_callback_(reinterpret_cast<v8::Isolate*>(isolate));
+  return infos;
+}
 
 HeapSnapshot* HeapProfiler::TakeSnapshot(
     v8::ActivityControl* control,
     v8::HeapProfiler::ObjectNameResolver* resolver) {
   HeapSnapshot* result = new HeapSnapshot(this);
   {
     HeapSnapshotGenerator generator(result, control, resolver, heap());
     if (!generator.GenerateSnapshot()) {
       delete result;
       result = NULL;
@@ skipping 143 matching lines @@
   ids_.reset(new HeapObjectsMap(heap()));
   if (!is_tracking_allocations()) is_tracking_object_moves_ = false;
 }
 
 
 Heap* HeapProfiler::heap() const { return ids_->heap(); }
 
 
 }  // namespace internal
 }  // namespace v8