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1/*********************************************************************
2 * NAN - Native Abstractions for Node.js
3 *
4 * Copyright (c) 2018 NAN contributors
5 *
6 * MIT License <https://github.com/nodejs/nan/blob/master/LICENSE.md>
7 ********************************************************************/
8
9#ifndef NAN_TYPEDARRAY_CONTENTS_H_
10#define NAN_TYPEDARRAY_CONTENTS_H_
11
12template<typename T>
13class TypedArrayContents {
14 public:
15 inline explicit TypedArrayContents(v8::Local<v8::Value> from) :
16 length_(0), data_(NULL) {
17 HandleScope scope;
18
19 size_t length = 0;
20 void* data = NULL;
21
22#if defined(V8_MAJOR_VERSION) && (V8_MAJOR_VERSION > 4 || \
23 (V8_MAJOR_VERSION == 4 && defined(V8_MINOR_VERSION) && V8_MINOR_VERSION >= 3))
24
25 if (from->IsArrayBufferView()) {
26 v8::Local<v8::ArrayBufferView> array =
27 v8::Local<v8::ArrayBufferView>::Cast(from);
28
29 const size_t byte_length = array->ByteLength();
30 const ptrdiff_t byte_offset = array->ByteOffset();
31 v8::Local<v8::ArrayBuffer> buffer = array->Buffer();
32
33 length = byte_length / sizeof(T);
34 data = static_cast<char*>(buffer->GetContents().Data()) + byte_offset;
35 }
36
37#else
38
39 if (from->IsObject() && !from->IsNull()) {
40 v8::Local<v8::Object> array = v8::Local<v8::Object>::Cast(from);
41
42 MaybeLocal<v8::Value> buffer = Get(array,
43 New<v8::String>("buffer").ToLocalChecked());
44 MaybeLocal<v8::Value> byte_length = Get(array,
45 New<v8::String>("byteLength").ToLocalChecked());
46 MaybeLocal<v8::Value> byte_offset = Get(array,
47 New<v8::String>("byteOffset").ToLocalChecked());
48
49 if (!buffer.IsEmpty() &&
50 !byte_length.IsEmpty() && byte_length.ToLocalChecked()->IsUint32() &&
51 !byte_offset.IsEmpty() && byte_offset.ToLocalChecked()->IsUint32()) {
52 data = array->GetIndexedPropertiesExternalArrayData();
53 if(data) {
54 length = byte_length.ToLocalChecked()->Uint32Value() / sizeof(T);
55 }
56 }
57 }
58
59#endif
60
61#if defined(_MSC_VER) && _MSC_VER >= 1900 || __cplusplus >= 201103L
62 assert(reinterpret_cast<uintptr_t>(data) % alignof (T) == 0);
63#elif defined(_MSC_VER) && _MSC_VER >= 1600 || defined(__GNUC__)
64 assert(reinterpret_cast<uintptr_t>(data) % __alignof(T) == 0);
65#else
66 assert(reinterpret_cast<uintptr_t>(data) % sizeof (T) == 0);
67#endif
68
69 length_ = length;
70 data_ = static_cast<T*>(data);
71 }
72
73 inline size_t length() const { return length_; }
74 inline T* operator*() { return data_; }
75 inline const T* operator*() const { return data_; }
76
77 private:
78 NAN_DISALLOW_ASSIGN_COPY_MOVE(TypedArrayContents)
79
80 //Disable heap allocation
81 void *operator new(size_t size);
82 void operator delete(void *, size_t) {
83 abort();
84 }
85
86 size_t length_;
87 T* data_;
88};
89
90#endif // NAN_TYPEDARRAY_CONTENTS_H_