--- /dev/null
+/*********************************************************************
+ * NAN - Native Abstractions for Node.js
+ *
+ * Copyright (c) 2018 NAN contributors
+ *
+ * MIT License <https://github.com/nodejs/nan/blob/master/LICENSE.md>
+ ********************************************************************/
+
+#ifndef NAN_TYPEDARRAY_CONTENTS_H_
+#define NAN_TYPEDARRAY_CONTENTS_H_
+
+template<typename T>
+class TypedArrayContents {
+ public:
+ inline explicit TypedArrayContents(v8::Local<v8::Value> from) :
+ length_(0), data_(NULL) {
+ HandleScope scope;
+
+ size_t length = 0;
+ void* data = NULL;
+
+#if defined(V8_MAJOR_VERSION) && (V8_MAJOR_VERSION > 4 || \
+ (V8_MAJOR_VERSION == 4 && defined(V8_MINOR_VERSION) && V8_MINOR_VERSION >= 3))
+
+ if (from->IsArrayBufferView()) {
+ v8::Local<v8::ArrayBufferView> array =
+ v8::Local<v8::ArrayBufferView>::Cast(from);
+
+ const size_t byte_length = array->ByteLength();
+ const ptrdiff_t byte_offset = array->ByteOffset();
+ v8::Local<v8::ArrayBuffer> buffer = array->Buffer();
+
+ length = byte_length / sizeof(T);
+// Actually it's 7.9 here but this would lead to ABI issues with Node.js 13
+// using 7.8 till 13.2.0.
+#if (V8_MAJOR_VERSION >= 8)
+ data = static_cast<char*>(buffer->GetBackingStore()->Data()) + byte_offset;
+#else
+ data = static_cast<char*>(buffer->GetContents().Data()) + byte_offset;
+#endif
+ }
+
+#else
+
+ if (from->IsObject() && !from->IsNull()) {
+ v8::Local<v8::Object> array = v8::Local<v8::Object>::Cast(from);
+
+ MaybeLocal<v8::Value> buffer = Get(array,
+ New<v8::String>("buffer").ToLocalChecked());
+ MaybeLocal<v8::Value> byte_length = Get(array,
+ New<v8::String>("byteLength").ToLocalChecked());
+ MaybeLocal<v8::Value> byte_offset = Get(array,
+ New<v8::String>("byteOffset").ToLocalChecked());
+
+ if (!buffer.IsEmpty() &&
+ !byte_length.IsEmpty() && byte_length.ToLocalChecked()->IsUint32() &&
+ !byte_offset.IsEmpty() && byte_offset.ToLocalChecked()->IsUint32()) {
+ data = array->GetIndexedPropertiesExternalArrayData();
+ if(data) {
+ length = byte_length.ToLocalChecked()->Uint32Value() / sizeof(T);
+ }
+ }
+ }
+
+#endif
+
+#if defined(_MSC_VER) && _MSC_VER >= 1900 || __cplusplus >= 201103L
+ assert(reinterpret_cast<uintptr_t>(data) % alignof (T) == 0);
+#elif defined(_MSC_VER) && _MSC_VER >= 1600 || defined(__GNUC__)
+ assert(reinterpret_cast<uintptr_t>(data) % __alignof(T) == 0);
+#else
+ assert(reinterpret_cast<uintptr_t>(data) % sizeof (T) == 0);
+#endif
+
+ length_ = length;
+ data_ = static_cast<T*>(data);
+ }
+
+ inline size_t length() const { return length_; }
+ inline T* operator*() { return data_; }
+ inline const T* operator*() const { return data_; }
+
+ private:
+ NAN_DISALLOW_ASSIGN_COPY_MOVE(TypedArrayContents)
+
+ //Disable heap allocation
+ void *operator new(size_t size);
+ void operator delete(void *, size_t) {
+ abort();
+ }
+
+ size_t length_;
+ T* data_;
+};
+
+#endif // NAN_TYPEDARRAY_CONTENTS_H_