v8/src/arraybuffer.js
2015-03-09 13:25:44 +00:00

95 lines
2.6 KiB
JavaScript

// Copyright 2013 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
"use strict";
var $ArrayBuffer = global.ArrayBuffer;
// -------------------------------------------------------------------
function ArrayBufferConstructor(length) { // length = 1
if (%_IsConstructCall()) {
var byteLength = ToPositiveInteger(length, 'invalid_array_buffer_length');
%ArrayBufferInitialize(this, byteLength);
} else {
throw MakeTypeError('constructor_not_function', ["ArrayBuffer"]);
}
}
function ArrayBufferGetByteLen() {
if (!IS_ARRAYBUFFER(this)) {
throw MakeTypeError('incompatible_method_receiver',
['ArrayBuffer.prototype.byteLength', this]);
}
return %_ArrayBufferGetByteLength(this);
}
// ES6 Draft 15.13.5.5.3
function ArrayBufferSlice(start, end) {
if (!IS_ARRAYBUFFER(this)) {
throw MakeTypeError('incompatible_method_receiver',
['ArrayBuffer.prototype.slice', this]);
}
var relativeStart = TO_INTEGER(start);
if (!IS_UNDEFINED(end)) {
end = TO_INTEGER(end);
}
var first;
var byte_length = %_ArrayBufferGetByteLength(this);
if (relativeStart < 0) {
first = $max(byte_length + relativeStart, 0);
} else {
first = $min(relativeStart, byte_length);
}
var relativeEnd = IS_UNDEFINED(end) ? byte_length : end;
var fin;
if (relativeEnd < 0) {
fin = $max(byte_length + relativeEnd, 0);
} else {
fin = $min(relativeEnd, byte_length);
}
if (fin < first) {
fin = first;
}
var newLen = fin - first;
// TODO(dslomov): implement inheritance
var result = new $ArrayBuffer(newLen);
%ArrayBufferSliceImpl(this, result, first);
return result;
}
function ArrayBufferIsViewJS(obj) {
return %ArrayBufferIsView(obj);
}
function SetUpArrayBuffer() {
%CheckIsBootstrapping();
// Set up the ArrayBuffer constructor function.
%SetCode($ArrayBuffer, ArrayBufferConstructor);
%FunctionSetPrototype($ArrayBuffer, new $Object());
// Set up the constructor property on the ArrayBuffer prototype object.
%AddNamedProperty(
$ArrayBuffer.prototype, "constructor", $ArrayBuffer, DONT_ENUM);
%AddNamedProperty($ArrayBuffer.prototype,
symbolToStringTag, "ArrayBuffer", DONT_ENUM | READ_ONLY);
InstallGetter($ArrayBuffer.prototype, "byteLength", ArrayBufferGetByteLen);
InstallFunctions($ArrayBuffer, DONT_ENUM, $Array(
"isView", ArrayBufferIsViewJS
));
InstallFunctions($ArrayBuffer.prototype, DONT_ENUM, $Array(
"slice", ArrayBufferSlice
));
}
SetUpArrayBuffer();