Externalization API for ArrayBuffer

src/runtime.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 640 matching lines @@
   return isolate->heap()->undefined_value();
 }
 
 
 static void ArrayBufferWeakCallback(v8::Isolate* external_isolate,
                                     Persistent<Value>* object,
                                     void* data) {
   Isolate* isolate = reinterpret_cast<Isolate*>(external_isolate);
   HandleScope scope(isolate);
   Handle<Object> internal_object = Utils::OpenHandle(**object);
+  Handle<JSArrayBuffer> array_buffer(JSArrayBuffer::cast(*internal_object));
 
-  size_t allocated_length = NumberToSize(
-      isolate, JSArrayBuffer::cast(*internal_object)->byte_length());
-  isolate->heap()->AdjustAmountOfExternalAllocatedMemory(
-      -static_cast<intptr_t>(allocated_length));
-  if (data != NULL)
+  if (!array_buffer->is_external()) {
+    size_t allocated_length = NumberToSize(
+        isolate, array_buffer->byte_length());
+    isolate->heap()->AdjustAmountOfExternalAllocatedMemory(
+        -static_cast<intptr_t>(allocated_length));
     free(data);
+  }
   object->Dispose(external_isolate);
 }
 
 
-bool Runtime::SetupArrayBuffer(Isolate* isolate,
+void Runtime::SetupArrayBuffer(Isolate* isolate,
                                Handle<JSArrayBuffer> array_buffer,
+                               bool is_external,
                                void* data,
                                size_t allocated_length) {
+  ASSERT(array_buffer->GetInternalFieldCount() ==
+      v8::ArrayBuffer::kInternalFieldCount);
+  for (int i = 0; i < v8::ArrayBuffer::kInternalFieldCount; i++) {
+    array_buffer->SetInternalField(i, Smi::FromInt(0));
+  }
   array_buffer->set_backing_store(data);
+  array_buffer->set_flag(Smi::FromInt(0));
+  array_buffer->set_is_external(is_external);
 
   Handle<Object> byte_length =
       isolate->factory()->NewNumberFromSize(allocated_length);
   CHECK(byte_length->IsSmi() || byte_length->IsHeapNumber());
   array_buffer->set_byte_length(*byte_length);
-  return true;
 }
 
 
 bool Runtime::SetupArrayBufferAllocatingData(
     Isolate* isolate,
     Handle<JSArrayBuffer> array_buffer,
     size_t allocated_length) {
   void* data;
   if (allocated_length != 0) {
     data = malloc(allocated_length);
     if (data == NULL) return false;
     memset(data, 0, allocated_length);
   } else {
     data = NULL;
   }
 
-  if (!SetupArrayBuffer(isolate, array_buffer, data, allocated_length))
-    return false;
+  SetupArrayBuffer(isolate, array_buffer, false, data, allocated_length);
 
   v8::Isolate* external_isolate = reinterpret_cast<v8::Isolate*>(isolate);
   v8::Persistent<v8::Value> weak_handle = v8::Persistent<v8::Value>::New(
       external_isolate, v8::Utils::ToLocal(Handle<Object>::cast(array_buffer)));
   weak_handle.MakeWeak(external_isolate, data, ArrayBufferWeakCallback);
   weak_handle.MarkIndependent(external_isolate);
   isolate->heap()->AdjustAmountOfExternalAllocatedMemory(allocated_length);
 
   return true;
 }
@@ skipping 12793 matching lines @@
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     isolate->counters()->gc_last_resort_from_js()->Increment();
     isolate->heap()->CollectAllGarbage(Heap::kNoGCFlags,
                                        "Runtime::PerformGC");
   }
 }
 
 
 } }  // namespace v8::internal