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1// Copyright 2013 the V8 project authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5"use strict";
6
7var $ArrayBuffer = global.ArrayBuffer;
8
9// -------------------------------------------------------------------
10
11function ArrayBufferConstructor(length) { // length = 1
12  if (%_IsConstructCall()) {
13    var byteLength = ToPositiveInteger(length, 'invalid_array_buffer_length');
14    %ArrayBufferInitialize(this, byteLength);
15  } else {
16    throw MakeTypeError('constructor_not_function', ["ArrayBuffer"]);
17  }
18}
19
20function ArrayBufferGetByteLen() {
21  if (!IS_ARRAYBUFFER(this)) {
22    throw MakeTypeError('incompatible_method_receiver',
23                        ['ArrayBuffer.prototype.byteLength', this]);
24  }
25  return %_ArrayBufferGetByteLength(this);
26}
27
28// ES6 Draft 15.13.5.5.3
29function ArrayBufferSlice(start, end) {
30  if (!IS_ARRAYBUFFER(this)) {
31    throw MakeTypeError('incompatible_method_receiver',
32                        ['ArrayBuffer.prototype.slice', this]);
33  }
34
35  var relativeStart = TO_INTEGER(start);
36  if (!IS_UNDEFINED(end)) {
37    end = TO_INTEGER(end);
38  }
39  var first;
40  var byte_length = %_ArrayBufferGetByteLength(this);
41  if (relativeStart < 0) {
42    first = MathMax(byte_length + relativeStart, 0);
43  } else {
44    first = MathMin(relativeStart, byte_length);
45  }
46  var relativeEnd = IS_UNDEFINED(end) ? byte_length : end;
47  var fin;
48  if (relativeEnd < 0) {
49    fin = MathMax(byte_length + relativeEnd, 0);
50  } else {
51    fin = MathMin(relativeEnd, byte_length);
52  }
53
54  if (fin < first) {
55    fin = first;
56  }
57  var newLen = fin - first;
58  // TODO(dslomov): implement inheritance
59  var result = new $ArrayBuffer(newLen);
60
61  %ArrayBufferSliceImpl(this, result, first);
62  return result;
63}
64
65function ArrayBufferIsViewJS(obj) {
66  return %ArrayBufferIsView(obj);
67}
68
69function SetUpArrayBuffer() {
70  %CheckIsBootstrapping();
71
72  // Set up the ArrayBuffer constructor function.
73  %SetCode($ArrayBuffer, ArrayBufferConstructor);
74  %FunctionSetPrototype($ArrayBuffer, new $Object());
75
76  // Set up the constructor property on the ArrayBuffer prototype object.
77  %AddNamedProperty(
78      $ArrayBuffer.prototype, "constructor", $ArrayBuffer, DONT_ENUM);
79
80  InstallGetter($ArrayBuffer.prototype, "byteLength", ArrayBufferGetByteLen);
81
82  InstallFunctions($ArrayBuffer, DONT_ENUM, $Array(
83      "isView", ArrayBufferIsViewJS
84  ));
85
86  InstallFunctions($ArrayBuffer.prototype, DONT_ENUM, $Array(
87      "slice", ArrayBufferSlice
88  ));
89}
90
91SetUpArrayBuffer();
92