if (actual > 0) [[likely]] {

if (actual < length) {

std::unique_ptr<BackingStore> old_store = std::move(store);

store = ArrayBuffer::NewBackingStore(isolate, actual);

store = ArrayBuffer::NewBackingStore(

isolate, actual, BackingStoreInitializationMode::kUninitialized);

memcpy(store->Data(), old_store->Data(), actual);

}

Local<ArrayBuffer> buf = ArrayBuffer::New(isolate, std::move(store));

CHECK(bs);

memcpy(bs->Data(), data, length);

if (length > 0) memcpy(bs->Data(), data, length);

Local<ArrayBuffer> ab = ArrayBuffer::New(isolate, std::move(bs));

}

}

#if defined(V8_ENABLE_SANDBOX)

// When v8 sandbox is enabled, external backing stores are not supported

// since all arraybuffer allocations are expected to be done by the isolate.

// Since this violates the contract of this function, let's free the data and

// throw an error.

free(data);

THROW_ERR_OPERATION_FAILED(

env->isolate(),

"Wrapping external data is not supported when the v8 sandbox is enabled");

return MaybeLocal<Object>();

#else

EscapableHandleScope handle_scope(env->isolate());

auto free_callback = [](void* data, size_t length, void* deleter_data) {

if (Buffer::New(env, ab, 0, length).ToLocal(&obj))

return handle_scope.Escape(obj);

return Local<Object>();

#endif

}

namespace {