| // Copyright 2014 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| define("mojo/public/js/buffer", function() { |
| |
| var kHostIsLittleEndian = (function () { |
| var endianArrayBuffer = new ArrayBuffer(2); |
| var endianUint8Array = new Uint8Array(endianArrayBuffer); |
| var endianUint16Array = new Uint16Array(endianArrayBuffer); |
| endianUint16Array[0] = 1; |
| return endianUint8Array[0] == 1; |
| })(); |
| |
| var kHighWordMultiplier = 0x100000000; |
| |
| function Buffer(sizeOrArrayBuffer) { |
| if (sizeOrArrayBuffer instanceof ArrayBuffer) |
| this.arrayBuffer = sizeOrArrayBuffer; |
| else |
| this.arrayBuffer = new ArrayBuffer(sizeOrArrayBuffer); |
| |
| this.dataView = new DataView(this.arrayBuffer); |
| this.next = 0; |
| } |
| |
| Object.defineProperty(Buffer.prototype, "byteLength", { |
| get: function() { return this.arrayBuffer.byteLength; } |
| }); |
| |
| Buffer.prototype.alloc = function(size) { |
| var pointer = this.next; |
| this.next += size; |
| if (this.next > this.byteLength) { |
| var newSize = (1.5 * (this.byteLength + size)) | 0; |
| this.grow(newSize); |
| } |
| return pointer; |
| }; |
| |
| function copyArrayBuffer(dstArrayBuffer, srcArrayBuffer) { |
| (new Uint8Array(dstArrayBuffer)).set(new Uint8Array(srcArrayBuffer)); |
| } |
| |
| Buffer.prototype.grow = function(size) { |
| var newArrayBuffer = new ArrayBuffer(size); |
| copyArrayBuffer(newArrayBuffer, this.arrayBuffer); |
| this.arrayBuffer = newArrayBuffer; |
| this.dataView = new DataView(this.arrayBuffer); |
| }; |
| |
| Buffer.prototype.trim = function() { |
| this.arrayBuffer = this.arrayBuffer.slice(0, this.next); |
| this.dataView = new DataView(this.arrayBuffer); |
| }; |
| |
| Buffer.prototype.getUint8 = function(offset) { |
| return this.dataView.getUint8(offset); |
| } |
| Buffer.prototype.getUint16 = function(offset) { |
| return this.dataView.getUint16(offset, kHostIsLittleEndian); |
| } |
| Buffer.prototype.getUint32 = function(offset) { |
| return this.dataView.getUint32(offset, kHostIsLittleEndian); |
| } |
| Buffer.prototype.getUint64 = function(offset) { |
| var lo, hi; |
| if (kHostIsLittleEndian) { |
| lo = this.dataView.getUint32(offset, kHostIsLittleEndian); |
| hi = this.dataView.getUint32(offset + 4, kHostIsLittleEndian); |
| } else { |
| hi = this.dataView.getUint32(offset, kHostIsLittleEndian); |
| lo = this.dataView.getUint32(offset + 4, kHostIsLittleEndian); |
| } |
| return lo + hi * kHighWordMultiplier; |
| } |
| |
| Buffer.prototype.getInt8 = function(offset) { |
| return this.dataView.getInt8(offset); |
| } |
| Buffer.prototype.getInt16 = function(offset) { |
| return this.dataView.getInt16(offset, kHostIsLittleEndian); |
| } |
| Buffer.prototype.getInt32 = function(offset) { |
| return this.dataView.getInt32(offset, kHostIsLittleEndian); |
| } |
| Buffer.prototype.getInt64 = function(offset) { |
| var lo, hi; |
| if (kHostIsLittleEndian) { |
| lo = this.dataView.getUint32(offset, kHostIsLittleEndian); |
| hi = this.dataView.getInt32(offset + 4, kHostIsLittleEndian); |
| } else { |
| hi = this.dataView.getInt32(offset, kHostIsLittleEndian); |
| lo = this.dataView.getUint32(offset + 4, kHostIsLittleEndian); |
| } |
| return lo + hi * kHighWordMultiplier; |
| } |
| |
| Buffer.prototype.getFloat32 = function(offset) { |
| return this.dataView.getFloat32(offset, kHostIsLittleEndian); |
| } |
| Buffer.prototype.getFloat64 = function(offset) { |
| return this.dataView.getFloat64(offset, kHostIsLittleEndian); |
| } |
| |
| Buffer.prototype.setUint8 = function(offset, value) { |
| this.dataView.setUint8(offset, value); |
| } |
| Buffer.prototype.setUint16 = function(offset, value) { |
| this.dataView.setUint16(offset, value, kHostIsLittleEndian); |
| } |
| Buffer.prototype.setUint32 = function(offset, value) { |
| this.dataView.setUint32(offset, value, kHostIsLittleEndian); |
| } |
| Buffer.prototype.setUint64 = function(offset, value) { |
| var hi = (value / kHighWordMultiplier) | 0; |
| if (kHostIsLittleEndian) { |
| this.dataView.setInt32(offset, value, kHostIsLittleEndian); |
| this.dataView.setInt32(offset + 4, hi, kHostIsLittleEndian); |
| } else { |
| this.dataView.setInt32(offset, hi, kHostIsLittleEndian); |
| this.dataView.setInt32(offset + 4, value, kHostIsLittleEndian); |
| } |
| } |
| |
| Buffer.prototype.setInt8 = function(offset, value) { |
| this.dataView.setInt8(offset, value); |
| } |
| Buffer.prototype.setInt16 = function(offset, value) { |
| this.dataView.setInt16(offset, value, kHostIsLittleEndian); |
| } |
| Buffer.prototype.setInt32 = function(offset, value) { |
| this.dataView.setInt32(offset, value, kHostIsLittleEndian); |
| } |
| Buffer.prototype.setInt64 = function(offset, value) { |
| var hi = Math.floor(value / kHighWordMultiplier); |
| if (kHostIsLittleEndian) { |
| this.dataView.setInt32(offset, value, kHostIsLittleEndian); |
| this.dataView.setInt32(offset + 4, hi, kHostIsLittleEndian); |
| } else { |
| this.dataView.setInt32(offset, hi, kHostIsLittleEndian); |
| this.dataView.setInt32(offset + 4, value, kHostIsLittleEndian); |
| } |
| } |
| |
| Buffer.prototype.setFloat32 = function(offset, value) { |
| this.dataView.setFloat32(offset, value, kHostIsLittleEndian); |
| } |
| Buffer.prototype.setFloat64 = function(offset, value) { |
| this.dataView.setFloat64(offset, value, kHostIsLittleEndian); |
| } |
| |
| var exports = {}; |
| exports.Buffer = Buffer; |
| return exports; |
| }); |