2908 lines
75 KiB
JavaScript
2908 lines
75 KiB
JavaScript
/**
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* Utility functions for web applications.
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*
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* @author Dave Longley
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*
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* Copyright (c) 2010-2018 Digital Bazaar, Inc.
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*/
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var forge = require('./forge');
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var baseN = require('./baseN');
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/* Utilities API */
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var util = module.exports = forge.util = forge.util || {};
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// define setImmediate and nextTick
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(function() {
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// use native nextTick (unless we're in webpack)
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// webpack (or better node-libs-browser polyfill) sets process.browser.
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// this way we can detect webpack properly
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if(typeof process !== 'undefined' && process.nextTick && !process.browser) {
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util.nextTick = process.nextTick;
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if(typeof setImmediate === 'function') {
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util.setImmediate = setImmediate;
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} else {
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// polyfill setImmediate with nextTick, older versions of node
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// (those w/o setImmediate) won't totally starve IO
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util.setImmediate = util.nextTick;
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}
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return;
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}
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// polyfill nextTick with native setImmediate
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if(typeof setImmediate === 'function') {
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util.setImmediate = function() { return setImmediate.apply(undefined, arguments); };
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util.nextTick = function(callback) {
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return setImmediate(callback);
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};
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return;
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}
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/* Note: A polyfill upgrade pattern is used here to allow combining
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polyfills. For example, MutationObserver is fast, but blocks UI updates,
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so it needs to allow UI updates periodically, so it falls back on
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postMessage or setTimeout. */
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// polyfill with setTimeout
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util.setImmediate = function(callback) {
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setTimeout(callback, 0);
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};
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// upgrade polyfill to use postMessage
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if(typeof window !== 'undefined' &&
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typeof window.postMessage === 'function') {
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var msg = 'forge.setImmediate';
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var callbacks = [];
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util.setImmediate = function(callback) {
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callbacks.push(callback);
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// only send message when one hasn't been sent in
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// the current turn of the event loop
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if(callbacks.length === 1) {
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window.postMessage(msg, '*');
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}
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};
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function handler(event) {
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if(event.source === window && event.data === msg) {
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event.stopPropagation();
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var copy = callbacks.slice();
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callbacks.length = 0;
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copy.forEach(function(callback) {
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callback();
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});
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}
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}
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window.addEventListener('message', handler, true);
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}
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// upgrade polyfill to use MutationObserver
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if(typeof MutationObserver !== 'undefined') {
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// polyfill with MutationObserver
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var now = Date.now();
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var attr = true;
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var div = document.createElement('div');
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var callbacks = [];
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new MutationObserver(function() {
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var copy = callbacks.slice();
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callbacks.length = 0;
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copy.forEach(function(callback) {
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callback();
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});
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}).observe(div, {attributes: true});
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var oldSetImmediate = util.setImmediate;
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util.setImmediate = function(callback) {
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if(Date.now() - now > 15) {
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now = Date.now();
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oldSetImmediate(callback);
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} else {
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callbacks.push(callback);
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// only trigger observer when it hasn't been triggered in
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// the current turn of the event loop
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if(callbacks.length === 1) {
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div.setAttribute('a', attr = !attr);
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}
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}
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};
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}
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util.nextTick = util.setImmediate;
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})();
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// check if running under Node.js
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util.isNodejs =
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typeof process !== 'undefined' && process.versions && process.versions.node;
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// 'self' will also work in Web Workers (instance of WorkerGlobalScope) while
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// it will point to `window` in the main thread.
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// To remain compatible with older browsers, we fall back to 'window' if 'self'
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// is not available.
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util.globalScope = (function() {
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if(util.isNodejs) {
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return global;
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}
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return typeof self === 'undefined' ? window : self;
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})();
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// define isArray
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util.isArray = Array.isArray || function(x) {
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return Object.prototype.toString.call(x) === '[object Array]';
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};
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// define isArrayBuffer
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util.isArrayBuffer = function(x) {
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return typeof ArrayBuffer !== 'undefined' && x instanceof ArrayBuffer;
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};
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// define isArrayBufferView
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util.isArrayBufferView = function(x) {
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return x && util.isArrayBuffer(x.buffer) && x.byteLength !== undefined;
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};
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/**
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* Ensure a bits param is 8, 16, 24, or 32. Used to validate input for
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* algorithms where bit manipulation, JavaScript limitations, and/or algorithm
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* design only allow for byte operations of a limited size.
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*
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* @param n number of bits.
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*
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* Throw Error if n invalid.
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*/
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function _checkBitsParam(n) {
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if(!(n === 8 || n === 16 || n === 24 || n === 32)) {
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throw new Error('Only 8, 16, 24, or 32 bits supported: ' + n);
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}
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}
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// TODO: set ByteBuffer to best available backing
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util.ByteBuffer = ByteStringBuffer;
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/** Buffer w/BinaryString backing */
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/**
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* Constructor for a binary string backed byte buffer.
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*
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* @param [b] the bytes to wrap (either encoded as string, one byte per
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* character, or as an ArrayBuffer or Typed Array).
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*/
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function ByteStringBuffer(b) {
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// TODO: update to match DataBuffer API
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// the data in this buffer
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this.data = '';
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// the pointer for reading from this buffer
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this.read = 0;
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if(typeof b === 'string') {
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this.data = b;
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} else if(util.isArrayBuffer(b) || util.isArrayBufferView(b)) {
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if(typeof Buffer !== 'undefined' && b instanceof Buffer) {
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this.data = b.toString('binary');
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} else {
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// convert native buffer to forge buffer
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// FIXME: support native buffers internally instead
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var arr = new Uint8Array(b);
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try {
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this.data = String.fromCharCode.apply(null, arr);
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} catch(e) {
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for(var i = 0; i < arr.length; ++i) {
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this.putByte(arr[i]);
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}
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}
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}
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} else if(b instanceof ByteStringBuffer ||
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(typeof b === 'object' && typeof b.data === 'string' &&
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typeof b.read === 'number')) {
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// copy existing buffer
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this.data = b.data;
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this.read = b.read;
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}
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// used for v8 optimization
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this._constructedStringLength = 0;
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}
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util.ByteStringBuffer = ByteStringBuffer;
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/* Note: This is an optimization for V8-based browsers. When V8 concatenates
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a string, the strings are only joined logically using a "cons string" or
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"constructed/concatenated string". These containers keep references to one
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another and can result in very large memory usage. For example, if a 2MB
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string is constructed by concatenating 4 bytes together at a time, the
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memory usage will be ~44MB; so ~22x increase. The strings are only joined
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together when an operation requiring their joining takes place, such as
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substr(). This function is called when adding data to this buffer to ensure
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these types of strings are periodically joined to reduce the memory
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footprint. */
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var _MAX_CONSTRUCTED_STRING_LENGTH = 4096;
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util.ByteStringBuffer.prototype._optimizeConstructedString = function(x) {
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this._constructedStringLength += x;
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if(this._constructedStringLength > _MAX_CONSTRUCTED_STRING_LENGTH) {
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// this substr() should cause the constructed string to join
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this.data.substr(0, 1);
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this._constructedStringLength = 0;
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}
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};
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/**
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* Gets the number of bytes in this buffer.
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*
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* @return the number of bytes in this buffer.
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*/
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util.ByteStringBuffer.prototype.length = function() {
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return this.data.length - this.read;
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};
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/**
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* Gets whether or not this buffer is empty.
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*
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* @return true if this buffer is empty, false if not.
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*/
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util.ByteStringBuffer.prototype.isEmpty = function() {
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return this.length() <= 0;
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};
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/**
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* Puts a byte in this buffer.
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*
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* @param b the byte to put.
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*
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* @return this buffer.
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*/
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util.ByteStringBuffer.prototype.putByte = function(b) {
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return this.putBytes(String.fromCharCode(b));
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};
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/**
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* Puts a byte in this buffer N times.
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*
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* @param b the byte to put.
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* @param n the number of bytes of value b to put.
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*
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* @return this buffer.
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*/
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util.ByteStringBuffer.prototype.fillWithByte = function(b, n) {
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b = String.fromCharCode(b);
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var d = this.data;
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while(n > 0) {
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if(n & 1) {
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d += b;
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}
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n >>>= 1;
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if(n > 0) {
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b += b;
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}
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}
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this.data = d;
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this._optimizeConstructedString(n);
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return this;
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};
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/**
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* Puts bytes in this buffer.
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*
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* @param bytes the bytes (as a binary encoded string) to put.
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*
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* @return this buffer.
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*/
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util.ByteStringBuffer.prototype.putBytes = function(bytes) {
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this.data += bytes;
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this._optimizeConstructedString(bytes.length);
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return this;
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};
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/**
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* Puts a UTF-16 encoded string into this buffer.
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*
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* @param str the string to put.
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*
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* @return this buffer.
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*/
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util.ByteStringBuffer.prototype.putString = function(str) {
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return this.putBytes(util.encodeUtf8(str));
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};
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/**
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* Puts a 16-bit integer in this buffer in big-endian order.
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*
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* @param i the 16-bit integer.
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*
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* @return this buffer.
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*/
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util.ByteStringBuffer.prototype.putInt16 = function(i) {
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return this.putBytes(
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String.fromCharCode(i >> 8 & 0xFF) +
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String.fromCharCode(i & 0xFF));
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};
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/**
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* Puts a 24-bit integer in this buffer in big-endian order.
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*
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* @param i the 24-bit integer.
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*
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* @return this buffer.
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*/
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util.ByteStringBuffer.prototype.putInt24 = function(i) {
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return this.putBytes(
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String.fromCharCode(i >> 16 & 0xFF) +
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String.fromCharCode(i >> 8 & 0xFF) +
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String.fromCharCode(i & 0xFF));
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};
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/**
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* Puts a 32-bit integer in this buffer in big-endian order.
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*
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* @param i the 32-bit integer.
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*
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* @return this buffer.
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*/
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util.ByteStringBuffer.prototype.putInt32 = function(i) {
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return this.putBytes(
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String.fromCharCode(i >> 24 & 0xFF) +
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String.fromCharCode(i >> 16 & 0xFF) +
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String.fromCharCode(i >> 8 & 0xFF) +
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String.fromCharCode(i & 0xFF));
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};
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/**
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* Puts a 16-bit integer in this buffer in little-endian order.
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*
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* @param i the 16-bit integer.
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*
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* @return this buffer.
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*/
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util.ByteStringBuffer.prototype.putInt16Le = function(i) {
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return this.putBytes(
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String.fromCharCode(i & 0xFF) +
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String.fromCharCode(i >> 8 & 0xFF));
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};
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/**
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* Puts a 24-bit integer in this buffer in little-endian order.
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*
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* @param i the 24-bit integer.
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*
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* @return this buffer.
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*/
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util.ByteStringBuffer.prototype.putInt24Le = function(i) {
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return this.putBytes(
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String.fromCharCode(i & 0xFF) +
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String.fromCharCode(i >> 8 & 0xFF) +
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String.fromCharCode(i >> 16 & 0xFF));
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};
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/**
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* Puts a 32-bit integer in this buffer in little-endian order.
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*
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* @param i the 32-bit integer.
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*
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* @return this buffer.
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*/
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util.ByteStringBuffer.prototype.putInt32Le = function(i) {
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return this.putBytes(
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String.fromCharCode(i & 0xFF) +
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String.fromCharCode(i >> 8 & 0xFF) +
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String.fromCharCode(i >> 16 & 0xFF) +
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String.fromCharCode(i >> 24 & 0xFF));
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};
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/**
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* Puts an n-bit integer in this buffer in big-endian order.
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*
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* @param i the n-bit integer.
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* @param n the number of bits in the integer (8, 16, 24, or 32).
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*
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* @return this buffer.
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*/
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util.ByteStringBuffer.prototype.putInt = function(i, n) {
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_checkBitsParam(n);
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var bytes = '';
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do {
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n -= 8;
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bytes += String.fromCharCode((i >> n) & 0xFF);
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} while(n > 0);
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return this.putBytes(bytes);
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};
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/**
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* Puts a signed n-bit integer in this buffer in big-endian order. Two's
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* complement representation is used.
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*
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* @param i the n-bit integer.
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* @param n the number of bits in the integer (8, 16, 24, or 32).
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*
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* @return this buffer.
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*/
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util.ByteStringBuffer.prototype.putSignedInt = function(i, n) {
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// putInt checks n
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if(i < 0) {
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i += 2 << (n - 1);
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}
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return this.putInt(i, n);
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};
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/**
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* Puts the given buffer into this buffer.
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*
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* @param buffer the buffer to put into this one.
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*
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* @return this buffer.
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*/
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util.ByteStringBuffer.prototype.putBuffer = function(buffer) {
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return this.putBytes(buffer.getBytes());
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};
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/**
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* Gets a byte from this buffer and advances the read pointer by 1.
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*
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* @return the byte.
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*/
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util.ByteStringBuffer.prototype.getByte = function() {
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return this.data.charCodeAt(this.read++);
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};
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/**
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* Gets a uint16 from this buffer in big-endian order and advances the read
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* pointer by 2.
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*
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* @return the uint16.
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*/
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util.ByteStringBuffer.prototype.getInt16 = function() {
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var rval = (
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this.data.charCodeAt(this.read) << 8 ^
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this.data.charCodeAt(this.read + 1));
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this.read += 2;
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return rval;
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};
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/**
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* Gets a uint24 from this buffer in big-endian order and advances the read
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* pointer by 3.
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*
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* @return the uint24.
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*/
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util.ByteStringBuffer.prototype.getInt24 = function() {
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var rval = (
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this.data.charCodeAt(this.read) << 16 ^
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this.data.charCodeAt(this.read + 1) << 8 ^
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this.data.charCodeAt(this.read + 2));
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this.read += 3;
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return rval;
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};
|
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|
|
/**
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* Gets a uint32 from this buffer in big-endian order and advances the read
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* pointer by 4.
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*
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* @return the word.
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*/
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|
util.ByteStringBuffer.prototype.getInt32 = function() {
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var rval = (
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this.data.charCodeAt(this.read) << 24 ^
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this.data.charCodeAt(this.read + 1) << 16 ^
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this.data.charCodeAt(this.read + 2) << 8 ^
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this.data.charCodeAt(this.read + 3));
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this.read += 4;
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return rval;
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|
};
|
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|
|
/**
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* Gets a uint16 from this buffer in little-endian order and advances the read
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* pointer by 2.
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*
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* @return the uint16.
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*/
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|
util.ByteStringBuffer.prototype.getInt16Le = function() {
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var rval = (
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this.data.charCodeAt(this.read) ^
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this.data.charCodeAt(this.read + 1) << 8);
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this.read += 2;
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return rval;
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};
|
|
|
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/**
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* Gets a uint24 from this buffer in little-endian order and advances the read
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|
* pointer by 3.
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*
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* @return the uint24.
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|
*/
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|
util.ByteStringBuffer.prototype.getInt24Le = function() {
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var rval = (
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this.data.charCodeAt(this.read) ^
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this.data.charCodeAt(this.read + 1) << 8 ^
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this.data.charCodeAt(this.read + 2) << 16);
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this.read += 3;
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return rval;
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};
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|
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/**
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* Gets a uint32 from this buffer in little-endian order and advances the read
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* pointer by 4.
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*
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* @return the word.
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*/
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util.ByteStringBuffer.prototype.getInt32Le = function() {
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var rval = (
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this.data.charCodeAt(this.read) ^
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this.data.charCodeAt(this.read + 1) << 8 ^
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this.data.charCodeAt(this.read + 2) << 16 ^
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this.data.charCodeAt(this.read + 3) << 24);
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this.read += 4;
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return rval;
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};
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|
|
/**
|
|
* Gets an n-bit integer from this buffer in big-endian order and advances the
|
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* read pointer by ceil(n/8).
|
|
*
|
|
* @param n the number of bits in the integer (8, 16, 24, or 32).
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*
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* @return the integer.
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|
*/
|
|
util.ByteStringBuffer.prototype.getInt = function(n) {
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_checkBitsParam(n);
|
|
var rval = 0;
|
|
do {
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// TODO: Use (rval * 0x100) if adding support for 33 to 53 bits.
|
|
rval = (rval << 8) + this.data.charCodeAt(this.read++);
|
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n -= 8;
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|
} while(n > 0);
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Gets a signed n-bit integer from this buffer in big-endian order, using
|
|
* two's complement, and advances the read pointer by n/8.
|
|
*
|
|
* @param n the number of bits in the integer (8, 16, 24, or 32).
|
|
*
|
|
* @return the integer.
|
|
*/
|
|
util.ByteStringBuffer.prototype.getSignedInt = function(n) {
|
|
// getInt checks n
|
|
var x = this.getInt(n);
|
|
var max = 2 << (n - 2);
|
|
if(x >= max) {
|
|
x -= max << 1;
|
|
}
|
|
return x;
|
|
};
|
|
|
|
/**
|
|
* Reads bytes out as a binary encoded string and clears them from the
|
|
* buffer. Note that the resulting string is binary encoded (in node.js this
|
|
* encoding is referred to as `binary`, it is *not* `utf8`).
|
|
*
|
|
* @param count the number of bytes to read, undefined or null for all.
|
|
*
|
|
* @return a binary encoded string of bytes.
|
|
*/
|
|
util.ByteStringBuffer.prototype.getBytes = function(count) {
|
|
var rval;
|
|
if(count) {
|
|
// read count bytes
|
|
count = Math.min(this.length(), count);
|
|
rval = this.data.slice(this.read, this.read + count);
|
|
this.read += count;
|
|
} else if(count === 0) {
|
|
rval = '';
|
|
} else {
|
|
// read all bytes, optimize to only copy when needed
|
|
rval = (this.read === 0) ? this.data : this.data.slice(this.read);
|
|
this.clear();
|
|
}
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Gets a binary encoded string of the bytes from this buffer without
|
|
* modifying the read pointer.
|
|
*
|
|
* @param count the number of bytes to get, omit to get all.
|
|
*
|
|
* @return a string full of binary encoded characters.
|
|
*/
|
|
util.ByteStringBuffer.prototype.bytes = function(count) {
|
|
return (typeof(count) === 'undefined' ?
|
|
this.data.slice(this.read) :
|
|
this.data.slice(this.read, this.read + count));
|
|
};
|
|
|
|
/**
|
|
* Gets a byte at the given index without modifying the read pointer.
|
|
*
|
|
* @param i the byte index.
|
|
*
|
|
* @return the byte.
|
|
*/
|
|
util.ByteStringBuffer.prototype.at = function(i) {
|
|
return this.data.charCodeAt(this.read + i);
|
|
};
|
|
|
|
/**
|
|
* Puts a byte at the given index without modifying the read pointer.
|
|
*
|
|
* @param i the byte index.
|
|
* @param b the byte to put.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.ByteStringBuffer.prototype.setAt = function(i, b) {
|
|
this.data = this.data.substr(0, this.read + i) +
|
|
String.fromCharCode(b) +
|
|
this.data.substr(this.read + i + 1);
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Gets the last byte without modifying the read pointer.
|
|
*
|
|
* @return the last byte.
|
|
*/
|
|
util.ByteStringBuffer.prototype.last = function() {
|
|
return this.data.charCodeAt(this.data.length - 1);
|
|
};
|
|
|
|
/**
|
|
* Creates a copy of this buffer.
|
|
*
|
|
* @return the copy.
|
|
*/
|
|
util.ByteStringBuffer.prototype.copy = function() {
|
|
var c = util.createBuffer(this.data);
|
|
c.read = this.read;
|
|
return c;
|
|
};
|
|
|
|
/**
|
|
* Compacts this buffer.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.ByteStringBuffer.prototype.compact = function() {
|
|
if(this.read > 0) {
|
|
this.data = this.data.slice(this.read);
|
|
this.read = 0;
|
|
}
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Clears this buffer.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.ByteStringBuffer.prototype.clear = function() {
|
|
this.data = '';
|
|
this.read = 0;
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Shortens this buffer by triming bytes off of the end of this buffer.
|
|
*
|
|
* @param count the number of bytes to trim off.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.ByteStringBuffer.prototype.truncate = function(count) {
|
|
var len = Math.max(0, this.length() - count);
|
|
this.data = this.data.substr(this.read, len);
|
|
this.read = 0;
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Converts this buffer to a hexadecimal string.
|
|
*
|
|
* @return a hexadecimal string.
|
|
*/
|
|
util.ByteStringBuffer.prototype.toHex = function() {
|
|
var rval = '';
|
|
for(var i = this.read; i < this.data.length; ++i) {
|
|
var b = this.data.charCodeAt(i);
|
|
if(b < 16) {
|
|
rval += '0';
|
|
}
|
|
rval += b.toString(16);
|
|
}
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Converts this buffer to a UTF-16 string (standard JavaScript string).
|
|
*
|
|
* @return a UTF-16 string.
|
|
*/
|
|
util.ByteStringBuffer.prototype.toString = function() {
|
|
return util.decodeUtf8(this.bytes());
|
|
};
|
|
|
|
/** End Buffer w/BinaryString backing */
|
|
|
|
/** Buffer w/UInt8Array backing */
|
|
|
|
/**
|
|
* FIXME: Experimental. Do not use yet.
|
|
*
|
|
* Constructor for an ArrayBuffer-backed byte buffer.
|
|
*
|
|
* The buffer may be constructed from a string, an ArrayBuffer, DataView, or a
|
|
* TypedArray.
|
|
*
|
|
* If a string is given, its encoding should be provided as an option,
|
|
* otherwise it will default to 'binary'. A 'binary' string is encoded such
|
|
* that each character is one byte in length and size.
|
|
*
|
|
* If an ArrayBuffer, DataView, or TypedArray is given, it will be used
|
|
* *directly* without any copying. Note that, if a write to the buffer requires
|
|
* more space, the buffer will allocate a new backing ArrayBuffer to
|
|
* accommodate. The starting read and write offsets for the buffer may be
|
|
* given as options.
|
|
*
|
|
* @param [b] the initial bytes for this buffer.
|
|
* @param options the options to use:
|
|
* [readOffset] the starting read offset to use (default: 0).
|
|
* [writeOffset] the starting write offset to use (default: the
|
|
* length of the first parameter).
|
|
* [growSize] the minimum amount, in bytes, to grow the buffer by to
|
|
* accommodate writes (default: 1024).
|
|
* [encoding] the encoding ('binary', 'utf8', 'utf16', 'hex') for the
|
|
* first parameter, if it is a string (default: 'binary').
|
|
*/
|
|
function DataBuffer(b, options) {
|
|
// default options
|
|
options = options || {};
|
|
|
|
// pointers for read from/write to buffer
|
|
this.read = options.readOffset || 0;
|
|
this.growSize = options.growSize || 1024;
|
|
|
|
var isArrayBuffer = util.isArrayBuffer(b);
|
|
var isArrayBufferView = util.isArrayBufferView(b);
|
|
if(isArrayBuffer || isArrayBufferView) {
|
|
// use ArrayBuffer directly
|
|
if(isArrayBuffer) {
|
|
this.data = new DataView(b);
|
|
} else {
|
|
// TODO: adjust read/write offset based on the type of view
|
|
// or specify that this must be done in the options ... that the
|
|
// offsets are byte-based
|
|
this.data = new DataView(b.buffer, b.byteOffset, b.byteLength);
|
|
}
|
|
this.write = ('writeOffset' in options ?
|
|
options.writeOffset : this.data.byteLength);
|
|
return;
|
|
}
|
|
|
|
// initialize to empty array buffer and add any given bytes using putBytes
|
|
this.data = new DataView(new ArrayBuffer(0));
|
|
this.write = 0;
|
|
|
|
if(b !== null && b !== undefined) {
|
|
this.putBytes(b);
|
|
}
|
|
|
|
if('writeOffset' in options) {
|
|
this.write = options.writeOffset;
|
|
}
|
|
}
|
|
util.DataBuffer = DataBuffer;
|
|
|
|
/**
|
|
* Gets the number of bytes in this buffer.
|
|
*
|
|
* @return the number of bytes in this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.length = function() {
|
|
return this.write - this.read;
|
|
};
|
|
|
|
/**
|
|
* Gets whether or not this buffer is empty.
|
|
*
|
|
* @return true if this buffer is empty, false if not.
|
|
*/
|
|
util.DataBuffer.prototype.isEmpty = function() {
|
|
return this.length() <= 0;
|
|
};
|
|
|
|
/**
|
|
* Ensures this buffer has enough empty space to accommodate the given number
|
|
* of bytes. An optional parameter may be given that indicates a minimum
|
|
* amount to grow the buffer if necessary. If the parameter is not given,
|
|
* the buffer will be grown by some previously-specified default amount
|
|
* or heuristic.
|
|
*
|
|
* @param amount the number of bytes to accommodate.
|
|
* @param [growSize] the minimum amount, in bytes, to grow the buffer by if
|
|
* necessary.
|
|
*/
|
|
util.DataBuffer.prototype.accommodate = function(amount, growSize) {
|
|
if(this.length() >= amount) {
|
|
return this;
|
|
}
|
|
growSize = Math.max(growSize || this.growSize, amount);
|
|
|
|
// grow buffer
|
|
var src = new Uint8Array(
|
|
this.data.buffer, this.data.byteOffset, this.data.byteLength);
|
|
var dst = new Uint8Array(this.length() + growSize);
|
|
dst.set(src);
|
|
this.data = new DataView(dst.buffer);
|
|
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Puts a byte in this buffer.
|
|
*
|
|
* @param b the byte to put.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.putByte = function(b) {
|
|
this.accommodate(1);
|
|
this.data.setUint8(this.write++, b);
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Puts a byte in this buffer N times.
|
|
*
|
|
* @param b the byte to put.
|
|
* @param n the number of bytes of value b to put.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.fillWithByte = function(b, n) {
|
|
this.accommodate(n);
|
|
for(var i = 0; i < n; ++i) {
|
|
this.data.setUint8(b);
|
|
}
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Puts bytes in this buffer. The bytes may be given as a string, an
|
|
* ArrayBuffer, a DataView, or a TypedArray.
|
|
*
|
|
* @param bytes the bytes to put.
|
|
* @param [encoding] the encoding for the first parameter ('binary', 'utf8',
|
|
* 'utf16', 'hex'), if it is a string (default: 'binary').
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.putBytes = function(bytes, encoding) {
|
|
if(util.isArrayBufferView(bytes)) {
|
|
var src = new Uint8Array(bytes.buffer, bytes.byteOffset, bytes.byteLength);
|
|
var len = src.byteLength - src.byteOffset;
|
|
this.accommodate(len);
|
|
var dst = new Uint8Array(this.data.buffer, this.write);
|
|
dst.set(src);
|
|
this.write += len;
|
|
return this;
|
|
}
|
|
|
|
if(util.isArrayBuffer(bytes)) {
|
|
var src = new Uint8Array(bytes);
|
|
this.accommodate(src.byteLength);
|
|
var dst = new Uint8Array(this.data.buffer);
|
|
dst.set(src, this.write);
|
|
this.write += src.byteLength;
|
|
return this;
|
|
}
|
|
|
|
// bytes is a util.DataBuffer or equivalent
|
|
if(bytes instanceof util.DataBuffer ||
|
|
(typeof bytes === 'object' &&
|
|
typeof bytes.read === 'number' && typeof bytes.write === 'number' &&
|
|
util.isArrayBufferView(bytes.data))) {
|
|
var src = new Uint8Array(bytes.data.byteLength, bytes.read, bytes.length());
|
|
this.accommodate(src.byteLength);
|
|
var dst = new Uint8Array(bytes.data.byteLength, this.write);
|
|
dst.set(src);
|
|
this.write += src.byteLength;
|
|
return this;
|
|
}
|
|
|
|
if(bytes instanceof util.ByteStringBuffer) {
|
|
// copy binary string and process as the same as a string parameter below
|
|
bytes = bytes.data;
|
|
encoding = 'binary';
|
|
}
|
|
|
|
// string conversion
|
|
encoding = encoding || 'binary';
|
|
if(typeof bytes === 'string') {
|
|
var view;
|
|
|
|
// decode from string
|
|
if(encoding === 'hex') {
|
|
this.accommodate(Math.ceil(bytes.length / 2));
|
|
view = new Uint8Array(this.data.buffer, this.write);
|
|
this.write += util.binary.hex.decode(bytes, view, this.write);
|
|
return this;
|
|
}
|
|
if(encoding === 'base64') {
|
|
this.accommodate(Math.ceil(bytes.length / 4) * 3);
|
|
view = new Uint8Array(this.data.buffer, this.write);
|
|
this.write += util.binary.base64.decode(bytes, view, this.write);
|
|
return this;
|
|
}
|
|
|
|
// encode text as UTF-8 bytes
|
|
if(encoding === 'utf8') {
|
|
// encode as UTF-8 then decode string as raw binary
|
|
bytes = util.encodeUtf8(bytes);
|
|
encoding = 'binary';
|
|
}
|
|
|
|
// decode string as raw binary
|
|
if(encoding === 'binary' || encoding === 'raw') {
|
|
// one byte per character
|
|
this.accommodate(bytes.length);
|
|
view = new Uint8Array(this.data.buffer, this.write);
|
|
this.write += util.binary.raw.decode(view);
|
|
return this;
|
|
}
|
|
|
|
// encode text as UTF-16 bytes
|
|
if(encoding === 'utf16') {
|
|
// two bytes per character
|
|
this.accommodate(bytes.length * 2);
|
|
view = new Uint16Array(this.data.buffer, this.write);
|
|
this.write += util.text.utf16.encode(view);
|
|
return this;
|
|
}
|
|
|
|
throw new Error('Invalid encoding: ' + encoding);
|
|
}
|
|
|
|
throw Error('Invalid parameter: ' + bytes);
|
|
};
|
|
|
|
/**
|
|
* Puts the given buffer into this buffer.
|
|
*
|
|
* @param buffer the buffer to put into this one.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.putBuffer = function(buffer) {
|
|
this.putBytes(buffer);
|
|
buffer.clear();
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Puts a string into this buffer.
|
|
*
|
|
* @param str the string to put.
|
|
* @param [encoding] the encoding for the string (default: 'utf16').
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.putString = function(str) {
|
|
return this.putBytes(str, 'utf16');
|
|
};
|
|
|
|
/**
|
|
* Puts a 16-bit integer in this buffer in big-endian order.
|
|
*
|
|
* @param i the 16-bit integer.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.putInt16 = function(i) {
|
|
this.accommodate(2);
|
|
this.data.setInt16(this.write, i);
|
|
this.write += 2;
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Puts a 24-bit integer in this buffer in big-endian order.
|
|
*
|
|
* @param i the 24-bit integer.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.putInt24 = function(i) {
|
|
this.accommodate(3);
|
|
this.data.setInt16(this.write, i >> 8 & 0xFFFF);
|
|
this.data.setInt8(this.write, i >> 16 & 0xFF);
|
|
this.write += 3;
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Puts a 32-bit integer in this buffer in big-endian order.
|
|
*
|
|
* @param i the 32-bit integer.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.putInt32 = function(i) {
|
|
this.accommodate(4);
|
|
this.data.setInt32(this.write, i);
|
|
this.write += 4;
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Puts a 16-bit integer in this buffer in little-endian order.
|
|
*
|
|
* @param i the 16-bit integer.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.putInt16Le = function(i) {
|
|
this.accommodate(2);
|
|
this.data.setInt16(this.write, i, true);
|
|
this.write += 2;
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Puts a 24-bit integer in this buffer in little-endian order.
|
|
*
|
|
* @param i the 24-bit integer.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.putInt24Le = function(i) {
|
|
this.accommodate(3);
|
|
this.data.setInt8(this.write, i >> 16 & 0xFF);
|
|
this.data.setInt16(this.write, i >> 8 & 0xFFFF, true);
|
|
this.write += 3;
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Puts a 32-bit integer in this buffer in little-endian order.
|
|
*
|
|
* @param i the 32-bit integer.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.putInt32Le = function(i) {
|
|
this.accommodate(4);
|
|
this.data.setInt32(this.write, i, true);
|
|
this.write += 4;
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Puts an n-bit integer in this buffer in big-endian order.
|
|
*
|
|
* @param i the n-bit integer.
|
|
* @param n the number of bits in the integer (8, 16, 24, or 32).
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.putInt = function(i, n) {
|
|
_checkBitsParam(n);
|
|
this.accommodate(n / 8);
|
|
do {
|
|
n -= 8;
|
|
this.data.setInt8(this.write++, (i >> n) & 0xFF);
|
|
} while(n > 0);
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Puts a signed n-bit integer in this buffer in big-endian order. Two's
|
|
* complement representation is used.
|
|
*
|
|
* @param i the n-bit integer.
|
|
* @param n the number of bits in the integer.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.putSignedInt = function(i, n) {
|
|
_checkBitsParam(n);
|
|
this.accommodate(n / 8);
|
|
if(i < 0) {
|
|
i += 2 << (n - 1);
|
|
}
|
|
return this.putInt(i, n);
|
|
};
|
|
|
|
/**
|
|
* Gets a byte from this buffer and advances the read pointer by 1.
|
|
*
|
|
* @return the byte.
|
|
*/
|
|
util.DataBuffer.prototype.getByte = function() {
|
|
return this.data.getInt8(this.read++);
|
|
};
|
|
|
|
/**
|
|
* Gets a uint16 from this buffer in big-endian order and advances the read
|
|
* pointer by 2.
|
|
*
|
|
* @return the uint16.
|
|
*/
|
|
util.DataBuffer.prototype.getInt16 = function() {
|
|
var rval = this.data.getInt16(this.read);
|
|
this.read += 2;
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Gets a uint24 from this buffer in big-endian order and advances the read
|
|
* pointer by 3.
|
|
*
|
|
* @return the uint24.
|
|
*/
|
|
util.DataBuffer.prototype.getInt24 = function() {
|
|
var rval = (
|
|
this.data.getInt16(this.read) << 8 ^
|
|
this.data.getInt8(this.read + 2));
|
|
this.read += 3;
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Gets a uint32 from this buffer in big-endian order and advances the read
|
|
* pointer by 4.
|
|
*
|
|
* @return the word.
|
|
*/
|
|
util.DataBuffer.prototype.getInt32 = function() {
|
|
var rval = this.data.getInt32(this.read);
|
|
this.read += 4;
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Gets a uint16 from this buffer in little-endian order and advances the read
|
|
* pointer by 2.
|
|
*
|
|
* @return the uint16.
|
|
*/
|
|
util.DataBuffer.prototype.getInt16Le = function() {
|
|
var rval = this.data.getInt16(this.read, true);
|
|
this.read += 2;
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Gets a uint24 from this buffer in little-endian order and advances the read
|
|
* pointer by 3.
|
|
*
|
|
* @return the uint24.
|
|
*/
|
|
util.DataBuffer.prototype.getInt24Le = function() {
|
|
var rval = (
|
|
this.data.getInt8(this.read) ^
|
|
this.data.getInt16(this.read + 1, true) << 8);
|
|
this.read += 3;
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Gets a uint32 from this buffer in little-endian order and advances the read
|
|
* pointer by 4.
|
|
*
|
|
* @return the word.
|
|
*/
|
|
util.DataBuffer.prototype.getInt32Le = function() {
|
|
var rval = this.data.getInt32(this.read, true);
|
|
this.read += 4;
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Gets an n-bit integer from this buffer in big-endian order and advances the
|
|
* read pointer by n/8.
|
|
*
|
|
* @param n the number of bits in the integer (8, 16, 24, or 32).
|
|
*
|
|
* @return the integer.
|
|
*/
|
|
util.DataBuffer.prototype.getInt = function(n) {
|
|
_checkBitsParam(n);
|
|
var rval = 0;
|
|
do {
|
|
// TODO: Use (rval * 0x100) if adding support for 33 to 53 bits.
|
|
rval = (rval << 8) + this.data.getInt8(this.read++);
|
|
n -= 8;
|
|
} while(n > 0);
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Gets a signed n-bit integer from this buffer in big-endian order, using
|
|
* two's complement, and advances the read pointer by n/8.
|
|
*
|
|
* @param n the number of bits in the integer (8, 16, 24, or 32).
|
|
*
|
|
* @return the integer.
|
|
*/
|
|
util.DataBuffer.prototype.getSignedInt = function(n) {
|
|
// getInt checks n
|
|
var x = this.getInt(n);
|
|
var max = 2 << (n - 2);
|
|
if(x >= max) {
|
|
x -= max << 1;
|
|
}
|
|
return x;
|
|
};
|
|
|
|
/**
|
|
* Reads bytes out as a binary encoded string and clears them from the
|
|
* buffer.
|
|
*
|
|
* @param count the number of bytes to read, undefined or null for all.
|
|
*
|
|
* @return a binary encoded string of bytes.
|
|
*/
|
|
util.DataBuffer.prototype.getBytes = function(count) {
|
|
// TODO: deprecate this method, it is poorly named and
|
|
// this.toString('binary') replaces it
|
|
// add a toTypedArray()/toArrayBuffer() function
|
|
var rval;
|
|
if(count) {
|
|
// read count bytes
|
|
count = Math.min(this.length(), count);
|
|
rval = this.data.slice(this.read, this.read + count);
|
|
this.read += count;
|
|
} else if(count === 0) {
|
|
rval = '';
|
|
} else {
|
|
// read all bytes, optimize to only copy when needed
|
|
rval = (this.read === 0) ? this.data : this.data.slice(this.read);
|
|
this.clear();
|
|
}
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Gets a binary encoded string of the bytes from this buffer without
|
|
* modifying the read pointer.
|
|
*
|
|
* @param count the number of bytes to get, omit to get all.
|
|
*
|
|
* @return a string full of binary encoded characters.
|
|
*/
|
|
util.DataBuffer.prototype.bytes = function(count) {
|
|
// TODO: deprecate this method, it is poorly named, add "getString()"
|
|
return (typeof(count) === 'undefined' ?
|
|
this.data.slice(this.read) :
|
|
this.data.slice(this.read, this.read + count));
|
|
};
|
|
|
|
/**
|
|
* Gets a byte at the given index without modifying the read pointer.
|
|
*
|
|
* @param i the byte index.
|
|
*
|
|
* @return the byte.
|
|
*/
|
|
util.DataBuffer.prototype.at = function(i) {
|
|
return this.data.getUint8(this.read + i);
|
|
};
|
|
|
|
/**
|
|
* Puts a byte at the given index without modifying the read pointer.
|
|
*
|
|
* @param i the byte index.
|
|
* @param b the byte to put.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.setAt = function(i, b) {
|
|
this.data.setUint8(i, b);
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Gets the last byte without modifying the read pointer.
|
|
*
|
|
* @return the last byte.
|
|
*/
|
|
util.DataBuffer.prototype.last = function() {
|
|
return this.data.getUint8(this.write - 1);
|
|
};
|
|
|
|
/**
|
|
* Creates a copy of this buffer.
|
|
*
|
|
* @return the copy.
|
|
*/
|
|
util.DataBuffer.prototype.copy = function() {
|
|
return new util.DataBuffer(this);
|
|
};
|
|
|
|
/**
|
|
* Compacts this buffer.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.compact = function() {
|
|
if(this.read > 0) {
|
|
var src = new Uint8Array(this.data.buffer, this.read);
|
|
var dst = new Uint8Array(src.byteLength);
|
|
dst.set(src);
|
|
this.data = new DataView(dst);
|
|
this.write -= this.read;
|
|
this.read = 0;
|
|
}
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Clears this buffer.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.clear = function() {
|
|
this.data = new DataView(new ArrayBuffer(0));
|
|
this.read = this.write = 0;
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Shortens this buffer by triming bytes off of the end of this buffer.
|
|
*
|
|
* @param count the number of bytes to trim off.
|
|
*
|
|
* @return this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.truncate = function(count) {
|
|
this.write = Math.max(0, this.length() - count);
|
|
this.read = Math.min(this.read, this.write);
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
* Converts this buffer to a hexadecimal string.
|
|
*
|
|
* @return a hexadecimal string.
|
|
*/
|
|
util.DataBuffer.prototype.toHex = function() {
|
|
var rval = '';
|
|
for(var i = this.read; i < this.data.byteLength; ++i) {
|
|
var b = this.data.getUint8(i);
|
|
if(b < 16) {
|
|
rval += '0';
|
|
}
|
|
rval += b.toString(16);
|
|
}
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Converts this buffer to a string, using the given encoding. If no
|
|
* encoding is given, 'utf8' (UTF-8) is used.
|
|
*
|
|
* @param [encoding] the encoding to use: 'binary', 'utf8', 'utf16', 'hex',
|
|
* 'base64' (default: 'utf8').
|
|
*
|
|
* @return a string representation of the bytes in this buffer.
|
|
*/
|
|
util.DataBuffer.prototype.toString = function(encoding) {
|
|
var view = new Uint8Array(this.data, this.read, this.length());
|
|
encoding = encoding || 'utf8';
|
|
|
|
// encode to string
|
|
if(encoding === 'binary' || encoding === 'raw') {
|
|
return util.binary.raw.encode(view);
|
|
}
|
|
if(encoding === 'hex') {
|
|
return util.binary.hex.encode(view);
|
|
}
|
|
if(encoding === 'base64') {
|
|
return util.binary.base64.encode(view);
|
|
}
|
|
|
|
// decode to text
|
|
if(encoding === 'utf8') {
|
|
return util.text.utf8.decode(view);
|
|
}
|
|
if(encoding === 'utf16') {
|
|
return util.text.utf16.decode(view);
|
|
}
|
|
|
|
throw new Error('Invalid encoding: ' + encoding);
|
|
};
|
|
|
|
/** End Buffer w/UInt8Array backing */
|
|
|
|
/**
|
|
* Creates a buffer that stores bytes. A value may be given to populate the
|
|
* buffer with data. This value can either be string of encoded bytes or a
|
|
* regular string of characters. When passing a string of binary encoded
|
|
* bytes, the encoding `raw` should be given. This is also the default. When
|
|
* passing a string of characters, the encoding `utf8` should be given.
|
|
*
|
|
* @param [input] a string with encoded bytes to store in the buffer.
|
|
* @param [encoding] (default: 'raw', other: 'utf8').
|
|
*/
|
|
util.createBuffer = function(input, encoding) {
|
|
// TODO: deprecate, use new ByteBuffer() instead
|
|
encoding = encoding || 'raw';
|
|
if(input !== undefined && encoding === 'utf8') {
|
|
input = util.encodeUtf8(input);
|
|
}
|
|
return new util.ByteBuffer(input);
|
|
};
|
|
|
|
/**
|
|
* Fills a string with a particular value. If you want the string to be a byte
|
|
* string, pass in String.fromCharCode(theByte).
|
|
*
|
|
* @param c the character to fill the string with, use String.fromCharCode
|
|
* to fill the string with a byte value.
|
|
* @param n the number of characters of value c to fill with.
|
|
*
|
|
* @return the filled string.
|
|
*/
|
|
util.fillString = function(c, n) {
|
|
var s = '';
|
|
while(n > 0) {
|
|
if(n & 1) {
|
|
s += c;
|
|
}
|
|
n >>>= 1;
|
|
if(n > 0) {
|
|
c += c;
|
|
}
|
|
}
|
|
return s;
|
|
};
|
|
|
|
/**
|
|
* Performs a per byte XOR between two byte strings and returns the result as a
|
|
* string of bytes.
|
|
*
|
|
* @param s1 first string of bytes.
|
|
* @param s2 second string of bytes.
|
|
* @param n the number of bytes to XOR.
|
|
*
|
|
* @return the XOR'd result.
|
|
*/
|
|
util.xorBytes = function(s1, s2, n) {
|
|
var s3 = '';
|
|
var b = '';
|
|
var t = '';
|
|
var i = 0;
|
|
var c = 0;
|
|
for(; n > 0; --n, ++i) {
|
|
b = s1.charCodeAt(i) ^ s2.charCodeAt(i);
|
|
if(c >= 10) {
|
|
s3 += t;
|
|
t = '';
|
|
c = 0;
|
|
}
|
|
t += String.fromCharCode(b);
|
|
++c;
|
|
}
|
|
s3 += t;
|
|
return s3;
|
|
};
|
|
|
|
/**
|
|
* Converts a hex string into a 'binary' encoded string of bytes.
|
|
*
|
|
* @param hex the hexadecimal string to convert.
|
|
*
|
|
* @return the binary-encoded string of bytes.
|
|
*/
|
|
util.hexToBytes = function(hex) {
|
|
// TODO: deprecate: "Deprecated. Use util.binary.hex.decode instead."
|
|
var rval = '';
|
|
var i = 0;
|
|
if(hex.length & 1 == 1) {
|
|
// odd number of characters, convert first character alone
|
|
i = 1;
|
|
rval += String.fromCharCode(parseInt(hex[0], 16));
|
|
}
|
|
// convert 2 characters (1 byte) at a time
|
|
for(; i < hex.length; i += 2) {
|
|
rval += String.fromCharCode(parseInt(hex.substr(i, 2), 16));
|
|
}
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Converts a 'binary' encoded string of bytes to hex.
|
|
*
|
|
* @param bytes the byte string to convert.
|
|
*
|
|
* @return the string of hexadecimal characters.
|
|
*/
|
|
util.bytesToHex = function(bytes) {
|
|
// TODO: deprecate: "Deprecated. Use util.binary.hex.encode instead."
|
|
return util.createBuffer(bytes).toHex();
|
|
};
|
|
|
|
/**
|
|
* Converts an 32-bit integer to 4-big-endian byte string.
|
|
*
|
|
* @param i the integer.
|
|
*
|
|
* @return the byte string.
|
|
*/
|
|
util.int32ToBytes = function(i) {
|
|
return (
|
|
String.fromCharCode(i >> 24 & 0xFF) +
|
|
String.fromCharCode(i >> 16 & 0xFF) +
|
|
String.fromCharCode(i >> 8 & 0xFF) +
|
|
String.fromCharCode(i & 0xFF));
|
|
};
|
|
|
|
// base64 characters, reverse mapping
|
|
var _base64 =
|
|
'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=';
|
|
var _base64Idx = [
|
|
/*43 -43 = 0*/
|
|
/*'+', 1, 2, 3,'/' */
|
|
62, -1, -1, -1, 63,
|
|
|
|
/*'0','1','2','3','4','5','6','7','8','9' */
|
|
52, 53, 54, 55, 56, 57, 58, 59, 60, 61,
|
|
|
|
/*15, 16, 17,'=', 19, 20, 21 */
|
|
-1, -1, -1, 64, -1, -1, -1,
|
|
|
|
/*65 - 43 = 22*/
|
|
/*'A','B','C','D','E','F','G','H','I','J','K','L','M', */
|
|
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,
|
|
|
|
/*'N','O','P','Q','R','S','T','U','V','W','X','Y','Z' */
|
|
13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,
|
|
|
|
/*91 - 43 = 48 */
|
|
/*48, 49, 50, 51, 52, 53 */
|
|
-1, -1, -1, -1, -1, -1,
|
|
|
|
/*97 - 43 = 54*/
|
|
/*'a','b','c','d','e','f','g','h','i','j','k','l','m' */
|
|
26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,
|
|
|
|
/*'n','o','p','q','r','s','t','u','v','w','x','y','z' */
|
|
39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51
|
|
];
|
|
|
|
// base58 characters (Bitcoin alphabet)
|
|
var _base58 = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz';
|
|
|
|
/**
|
|
* Base64 encodes a 'binary' encoded string of bytes.
|
|
*
|
|
* @param input the binary encoded string of bytes to base64-encode.
|
|
* @param maxline the maximum number of encoded characters per line to use,
|
|
* defaults to none.
|
|
*
|
|
* @return the base64-encoded output.
|
|
*/
|
|
util.encode64 = function(input, maxline) {
|
|
// TODO: deprecate: "Deprecated. Use util.binary.base64.encode instead."
|
|
var line = '';
|
|
var output = '';
|
|
var chr1, chr2, chr3;
|
|
var i = 0;
|
|
while(i < input.length) {
|
|
chr1 = input.charCodeAt(i++);
|
|
chr2 = input.charCodeAt(i++);
|
|
chr3 = input.charCodeAt(i++);
|
|
|
|
// encode 4 character group
|
|
line += _base64.charAt(chr1 >> 2);
|
|
line += _base64.charAt(((chr1 & 3) << 4) | (chr2 >> 4));
|
|
if(isNaN(chr2)) {
|
|
line += '==';
|
|
} else {
|
|
line += _base64.charAt(((chr2 & 15) << 2) | (chr3 >> 6));
|
|
line += isNaN(chr3) ? '=' : _base64.charAt(chr3 & 63);
|
|
}
|
|
|
|
if(maxline && line.length > maxline) {
|
|
output += line.substr(0, maxline) + '\r\n';
|
|
line = line.substr(maxline);
|
|
}
|
|
}
|
|
output += line;
|
|
return output;
|
|
};
|
|
|
|
/**
|
|
* Base64 decodes a string into a 'binary' encoded string of bytes.
|
|
*
|
|
* @param input the base64-encoded input.
|
|
*
|
|
* @return the binary encoded string.
|
|
*/
|
|
util.decode64 = function(input) {
|
|
// TODO: deprecate: "Deprecated. Use util.binary.base64.decode instead."
|
|
|
|
// remove all non-base64 characters
|
|
input = input.replace(/[^A-Za-z0-9\+\/\=]/g, '');
|
|
|
|
var output = '';
|
|
var enc1, enc2, enc3, enc4;
|
|
var i = 0;
|
|
|
|
while(i < input.length) {
|
|
enc1 = _base64Idx[input.charCodeAt(i++) - 43];
|
|
enc2 = _base64Idx[input.charCodeAt(i++) - 43];
|
|
enc3 = _base64Idx[input.charCodeAt(i++) - 43];
|
|
enc4 = _base64Idx[input.charCodeAt(i++) - 43];
|
|
|
|
output += String.fromCharCode((enc1 << 2) | (enc2 >> 4));
|
|
if(enc3 !== 64) {
|
|
// decoded at least 2 bytes
|
|
output += String.fromCharCode(((enc2 & 15) << 4) | (enc3 >> 2));
|
|
if(enc4 !== 64) {
|
|
// decoded 3 bytes
|
|
output += String.fromCharCode(((enc3 & 3) << 6) | enc4);
|
|
}
|
|
}
|
|
}
|
|
|
|
return output;
|
|
};
|
|
|
|
/**
|
|
* Encodes the given string of characters (a standard JavaScript
|
|
* string) as a binary encoded string where the bytes represent
|
|
* a UTF-8 encoded string of characters. Non-ASCII characters will be
|
|
* encoded as multiple bytes according to UTF-8.
|
|
*
|
|
* @param str a standard string of characters to encode.
|
|
*
|
|
* @return the binary encoded string.
|
|
*/
|
|
util.encodeUtf8 = function(str) {
|
|
return unescape(encodeURIComponent(str));
|
|
};
|
|
|
|
/**
|
|
* Decodes a binary encoded string that contains bytes that
|
|
* represent a UTF-8 encoded string of characters -- into a
|
|
* string of characters (a standard JavaScript string).
|
|
*
|
|
* @param str the binary encoded string to decode.
|
|
*
|
|
* @return the resulting standard string of characters.
|
|
*/
|
|
util.decodeUtf8 = function(str) {
|
|
return decodeURIComponent(escape(str));
|
|
};
|
|
|
|
// binary encoding/decoding tools
|
|
// FIXME: Experimental. Do not use yet.
|
|
util.binary = {
|
|
raw: {},
|
|
hex: {},
|
|
base64: {},
|
|
base58: {},
|
|
baseN : {
|
|
encode: baseN.encode,
|
|
decode: baseN.decode
|
|
}
|
|
};
|
|
|
|
/**
|
|
* Encodes a Uint8Array as a binary-encoded string. This encoding uses
|
|
* a value between 0 and 255 for each character.
|
|
*
|
|
* @param bytes the Uint8Array to encode.
|
|
*
|
|
* @return the binary-encoded string.
|
|
*/
|
|
util.binary.raw.encode = function(bytes) {
|
|
return String.fromCharCode.apply(null, bytes);
|
|
};
|
|
|
|
/**
|
|
* Decodes a binary-encoded string to a Uint8Array. This encoding uses
|
|
* a value between 0 and 255 for each character.
|
|
*
|
|
* @param str the binary-encoded string to decode.
|
|
* @param [output] an optional Uint8Array to write the output to; if it
|
|
* is too small, an exception will be thrown.
|
|
* @param [offset] the start offset for writing to the output (default: 0).
|
|
*
|
|
* @return the Uint8Array or the number of bytes written if output was given.
|
|
*/
|
|
util.binary.raw.decode = function(str, output, offset) {
|
|
var out = output;
|
|
if(!out) {
|
|
out = new Uint8Array(str.length);
|
|
}
|
|
offset = offset || 0;
|
|
var j = offset;
|
|
for(var i = 0; i < str.length; ++i) {
|
|
out[j++] = str.charCodeAt(i);
|
|
}
|
|
return output ? (j - offset) : out;
|
|
};
|
|
|
|
/**
|
|
* Encodes a 'binary' string, ArrayBuffer, DataView, TypedArray, or
|
|
* ByteBuffer as a string of hexadecimal characters.
|
|
*
|
|
* @param bytes the bytes to convert.
|
|
*
|
|
* @return the string of hexadecimal characters.
|
|
*/
|
|
util.binary.hex.encode = util.bytesToHex;
|
|
|
|
/**
|
|
* Decodes a hex-encoded string to a Uint8Array.
|
|
*
|
|
* @param hex the hexadecimal string to convert.
|
|
* @param [output] an optional Uint8Array to write the output to; if it
|
|
* is too small, an exception will be thrown.
|
|
* @param [offset] the start offset for writing to the output (default: 0).
|
|
*
|
|
* @return the Uint8Array or the number of bytes written if output was given.
|
|
*/
|
|
util.binary.hex.decode = function(hex, output, offset) {
|
|
var out = output;
|
|
if(!out) {
|
|
out = new Uint8Array(Math.ceil(hex.length / 2));
|
|
}
|
|
offset = offset || 0;
|
|
var i = 0, j = offset;
|
|
if(hex.length & 1) {
|
|
// odd number of characters, convert first character alone
|
|
i = 1;
|
|
out[j++] = parseInt(hex[0], 16);
|
|
}
|
|
// convert 2 characters (1 byte) at a time
|
|
for(; i < hex.length; i += 2) {
|
|
out[j++] = parseInt(hex.substr(i, 2), 16);
|
|
}
|
|
return output ? (j - offset) : out;
|
|
};
|
|
|
|
/**
|
|
* Base64-encodes a Uint8Array.
|
|
*
|
|
* @param input the Uint8Array to encode.
|
|
* @param maxline the maximum number of encoded characters per line to use,
|
|
* defaults to none.
|
|
*
|
|
* @return the base64-encoded output string.
|
|
*/
|
|
util.binary.base64.encode = function(input, maxline) {
|
|
var line = '';
|
|
var output = '';
|
|
var chr1, chr2, chr3;
|
|
var i = 0;
|
|
while(i < input.byteLength) {
|
|
chr1 = input[i++];
|
|
chr2 = input[i++];
|
|
chr3 = input[i++];
|
|
|
|
// encode 4 character group
|
|
line += _base64.charAt(chr1 >> 2);
|
|
line += _base64.charAt(((chr1 & 3) << 4) | (chr2 >> 4));
|
|
if(isNaN(chr2)) {
|
|
line += '==';
|
|
} else {
|
|
line += _base64.charAt(((chr2 & 15) << 2) | (chr3 >> 6));
|
|
line += isNaN(chr3) ? '=' : _base64.charAt(chr3 & 63);
|
|
}
|
|
|
|
if(maxline && line.length > maxline) {
|
|
output += line.substr(0, maxline) + '\r\n';
|
|
line = line.substr(maxline);
|
|
}
|
|
}
|
|
output += line;
|
|
return output;
|
|
};
|
|
|
|
/**
|
|
* Decodes a base64-encoded string to a Uint8Array.
|
|
*
|
|
* @param input the base64-encoded input string.
|
|
* @param [output] an optional Uint8Array to write the output to; if it
|
|
* is too small, an exception will be thrown.
|
|
* @param [offset] the start offset for writing to the output (default: 0).
|
|
*
|
|
* @return the Uint8Array or the number of bytes written if output was given.
|
|
*/
|
|
util.binary.base64.decode = function(input, output, offset) {
|
|
var out = output;
|
|
if(!out) {
|
|
out = new Uint8Array(Math.ceil(input.length / 4) * 3);
|
|
}
|
|
|
|
// remove all non-base64 characters
|
|
input = input.replace(/[^A-Za-z0-9\+\/\=]/g, '');
|
|
|
|
offset = offset || 0;
|
|
var enc1, enc2, enc3, enc4;
|
|
var i = 0, j = offset;
|
|
|
|
while(i < input.length) {
|
|
enc1 = _base64Idx[input.charCodeAt(i++) - 43];
|
|
enc2 = _base64Idx[input.charCodeAt(i++) - 43];
|
|
enc3 = _base64Idx[input.charCodeAt(i++) - 43];
|
|
enc4 = _base64Idx[input.charCodeAt(i++) - 43];
|
|
|
|
out[j++] = (enc1 << 2) | (enc2 >> 4);
|
|
if(enc3 !== 64) {
|
|
// decoded at least 2 bytes
|
|
out[j++] = ((enc2 & 15) << 4) | (enc3 >> 2);
|
|
if(enc4 !== 64) {
|
|
// decoded 3 bytes
|
|
out[j++] = ((enc3 & 3) << 6) | enc4;
|
|
}
|
|
}
|
|
}
|
|
|
|
// make sure result is the exact decoded length
|
|
return output ? (j - offset) : out.subarray(0, j);
|
|
};
|
|
|
|
// add support for base58 encoding/decoding with Bitcoin alphabet
|
|
util.binary.base58.encode = function(input, maxline) {
|
|
return util.binary.baseN.encode(input, _base58, maxline);
|
|
};
|
|
util.binary.base58.decode = function(input, maxline) {
|
|
return util.binary.baseN.decode(input, _base58, maxline);
|
|
};
|
|
|
|
// text encoding/decoding tools
|
|
// FIXME: Experimental. Do not use yet.
|
|
util.text = {
|
|
utf8: {},
|
|
utf16: {}
|
|
};
|
|
|
|
/**
|
|
* Encodes the given string as UTF-8 in a Uint8Array.
|
|
*
|
|
* @param str the string to encode.
|
|
* @param [output] an optional Uint8Array to write the output to; if it
|
|
* is too small, an exception will be thrown.
|
|
* @param [offset] the start offset for writing to the output (default: 0).
|
|
*
|
|
* @return the Uint8Array or the number of bytes written if output was given.
|
|
*/
|
|
util.text.utf8.encode = function(str, output, offset) {
|
|
str = util.encodeUtf8(str);
|
|
var out = output;
|
|
if(!out) {
|
|
out = new Uint8Array(str.length);
|
|
}
|
|
offset = offset || 0;
|
|
var j = offset;
|
|
for(var i = 0; i < str.length; ++i) {
|
|
out[j++] = str.charCodeAt(i);
|
|
}
|
|
return output ? (j - offset) : out;
|
|
};
|
|
|
|
/**
|
|
* Decodes the UTF-8 contents from a Uint8Array.
|
|
*
|
|
* @param bytes the Uint8Array to decode.
|
|
*
|
|
* @return the resulting string.
|
|
*/
|
|
util.text.utf8.decode = function(bytes) {
|
|
return util.decodeUtf8(String.fromCharCode.apply(null, bytes));
|
|
};
|
|
|
|
/**
|
|
* Encodes the given string as UTF-16 in a Uint8Array.
|
|
*
|
|
* @param str the string to encode.
|
|
* @param [output] an optional Uint8Array to write the output to; if it
|
|
* is too small, an exception will be thrown.
|
|
* @param [offset] the start offset for writing to the output (default: 0).
|
|
*
|
|
* @return the Uint8Array or the number of bytes written if output was given.
|
|
*/
|
|
util.text.utf16.encode = function(str, output, offset) {
|
|
var out = output;
|
|
if(!out) {
|
|
out = new Uint8Array(str.length * 2);
|
|
}
|
|
var view = new Uint16Array(out.buffer);
|
|
offset = offset || 0;
|
|
var j = offset;
|
|
var k = offset;
|
|
for(var i = 0; i < str.length; ++i) {
|
|
view[k++] = str.charCodeAt(i);
|
|
j += 2;
|
|
}
|
|
return output ? (j - offset) : out;
|
|
};
|
|
|
|
/**
|
|
* Decodes the UTF-16 contents from a Uint8Array.
|
|
*
|
|
* @param bytes the Uint8Array to decode.
|
|
*
|
|
* @return the resulting string.
|
|
*/
|
|
util.text.utf16.decode = function(bytes) {
|
|
return String.fromCharCode.apply(null, new Uint16Array(bytes.buffer));
|
|
};
|
|
|
|
/**
|
|
* Deflates the given data using a flash interface.
|
|
*
|
|
* @param api the flash interface.
|
|
* @param bytes the data.
|
|
* @param raw true to return only raw deflate data, false to include zlib
|
|
* header and trailer.
|
|
*
|
|
* @return the deflated data as a string.
|
|
*/
|
|
util.deflate = function(api, bytes, raw) {
|
|
bytes = util.decode64(api.deflate(util.encode64(bytes)).rval);
|
|
|
|
// strip zlib header and trailer if necessary
|
|
if(raw) {
|
|
// zlib header is 2 bytes (CMF,FLG) where FLG indicates that
|
|
// there is a 4-byte DICT (alder-32) block before the data if
|
|
// its 5th bit is set
|
|
var start = 2;
|
|
var flg = bytes.charCodeAt(1);
|
|
if(flg & 0x20) {
|
|
start = 6;
|
|
}
|
|
// zlib trailer is 4 bytes of adler-32
|
|
bytes = bytes.substring(start, bytes.length - 4);
|
|
}
|
|
|
|
return bytes;
|
|
};
|
|
|
|
/**
|
|
* Inflates the given data using a flash interface.
|
|
*
|
|
* @param api the flash interface.
|
|
* @param bytes the data.
|
|
* @param raw true if the incoming data has no zlib header or trailer and is
|
|
* raw DEFLATE data.
|
|
*
|
|
* @return the inflated data as a string, null on error.
|
|
*/
|
|
util.inflate = function(api, bytes, raw) {
|
|
// TODO: add zlib header and trailer if necessary/possible
|
|
var rval = api.inflate(util.encode64(bytes)).rval;
|
|
return (rval === null) ? null : util.decode64(rval);
|
|
};
|
|
|
|
/**
|
|
* Sets a storage object.
|
|
*
|
|
* @param api the storage interface.
|
|
* @param id the storage ID to use.
|
|
* @param obj the storage object, null to remove.
|
|
*/
|
|
var _setStorageObject = function(api, id, obj) {
|
|
if(!api) {
|
|
throw new Error('WebStorage not available.');
|
|
}
|
|
|
|
var rval;
|
|
if(obj === null) {
|
|
rval = api.removeItem(id);
|
|
} else {
|
|
// json-encode and base64-encode object
|
|
obj = util.encode64(JSON.stringify(obj));
|
|
rval = api.setItem(id, obj);
|
|
}
|
|
|
|
// handle potential flash error
|
|
if(typeof(rval) !== 'undefined' && rval.rval !== true) {
|
|
var error = new Error(rval.error.message);
|
|
error.id = rval.error.id;
|
|
error.name = rval.error.name;
|
|
throw error;
|
|
}
|
|
};
|
|
|
|
/**
|
|
* Gets a storage object.
|
|
*
|
|
* @param api the storage interface.
|
|
* @param id the storage ID to use.
|
|
*
|
|
* @return the storage object entry or null if none exists.
|
|
*/
|
|
var _getStorageObject = function(api, id) {
|
|
if(!api) {
|
|
throw new Error('WebStorage not available.');
|
|
}
|
|
|
|
// get the existing entry
|
|
var rval = api.getItem(id);
|
|
|
|
/* Note: We check api.init because we can't do (api == localStorage)
|
|
on IE because of "Class doesn't support Automation" exception. Only
|
|
the flash api has an init method so this works too, but we need a
|
|
better solution in the future. */
|
|
|
|
// flash returns item wrapped in an object, handle special case
|
|
if(api.init) {
|
|
if(rval.rval === null) {
|
|
if(rval.error) {
|
|
var error = new Error(rval.error.message);
|
|
error.id = rval.error.id;
|
|
error.name = rval.error.name;
|
|
throw error;
|
|
}
|
|
// no error, but also no item
|
|
rval = null;
|
|
} else {
|
|
rval = rval.rval;
|
|
}
|
|
}
|
|
|
|
// handle decoding
|
|
if(rval !== null) {
|
|
// base64-decode and json-decode data
|
|
rval = JSON.parse(util.decode64(rval));
|
|
}
|
|
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Stores an item in local storage.
|
|
*
|
|
* @param api the storage interface.
|
|
* @param id the storage ID to use.
|
|
* @param key the key for the item.
|
|
* @param data the data for the item (any javascript object/primitive).
|
|
*/
|
|
var _setItem = function(api, id, key, data) {
|
|
// get storage object
|
|
var obj = _getStorageObject(api, id);
|
|
if(obj === null) {
|
|
// create a new storage object
|
|
obj = {};
|
|
}
|
|
// update key
|
|
obj[key] = data;
|
|
|
|
// set storage object
|
|
_setStorageObject(api, id, obj);
|
|
};
|
|
|
|
/**
|
|
* Gets an item from local storage.
|
|
*
|
|
* @param api the storage interface.
|
|
* @param id the storage ID to use.
|
|
* @param key the key for the item.
|
|
*
|
|
* @return the item.
|
|
*/
|
|
var _getItem = function(api, id, key) {
|
|
// get storage object
|
|
var rval = _getStorageObject(api, id);
|
|
if(rval !== null) {
|
|
// return data at key
|
|
rval = (key in rval) ? rval[key] : null;
|
|
}
|
|
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Removes an item from local storage.
|
|
*
|
|
* @param api the storage interface.
|
|
* @param id the storage ID to use.
|
|
* @param key the key for the item.
|
|
*/
|
|
var _removeItem = function(api, id, key) {
|
|
// get storage object
|
|
var obj = _getStorageObject(api, id);
|
|
if(obj !== null && key in obj) {
|
|
// remove key
|
|
delete obj[key];
|
|
|
|
// see if entry has no keys remaining
|
|
var empty = true;
|
|
for(var prop in obj) {
|
|
empty = false;
|
|
break;
|
|
}
|
|
if(empty) {
|
|
// remove entry entirely if no keys are left
|
|
obj = null;
|
|
}
|
|
|
|
// set storage object
|
|
_setStorageObject(api, id, obj);
|
|
}
|
|
};
|
|
|
|
/**
|
|
* Clears the local disk storage identified by the given ID.
|
|
*
|
|
* @param api the storage interface.
|
|
* @param id the storage ID to use.
|
|
*/
|
|
var _clearItems = function(api, id) {
|
|
_setStorageObject(api, id, null);
|
|
};
|
|
|
|
/**
|
|
* Calls a storage function.
|
|
*
|
|
* @param func the function to call.
|
|
* @param args the arguments for the function.
|
|
* @param location the location argument.
|
|
*
|
|
* @return the return value from the function.
|
|
*/
|
|
var _callStorageFunction = function(func, args, location) {
|
|
var rval = null;
|
|
|
|
// default storage types
|
|
if(typeof(location) === 'undefined') {
|
|
location = ['web', 'flash'];
|
|
}
|
|
|
|
// apply storage types in order of preference
|
|
var type;
|
|
var done = false;
|
|
var exception = null;
|
|
for(var idx in location) {
|
|
type = location[idx];
|
|
try {
|
|
if(type === 'flash' || type === 'both') {
|
|
if(args[0] === null) {
|
|
throw new Error('Flash local storage not available.');
|
|
}
|
|
rval = func.apply(this, args);
|
|
done = (type === 'flash');
|
|
}
|
|
if(type === 'web' || type === 'both') {
|
|
args[0] = localStorage;
|
|
rval = func.apply(this, args);
|
|
done = true;
|
|
}
|
|
} catch(ex) {
|
|
exception = ex;
|
|
}
|
|
if(done) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
if(!done) {
|
|
throw exception;
|
|
}
|
|
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Stores an item on local disk.
|
|
*
|
|
* The available types of local storage include 'flash', 'web', and 'both'.
|
|
*
|
|
* The type 'flash' refers to flash local storage (SharedObject). In order
|
|
* to use flash local storage, the 'api' parameter must be valid. The type
|
|
* 'web' refers to WebStorage, if supported by the browser. The type 'both'
|
|
* refers to storing using both 'flash' and 'web', not just one or the
|
|
* other.
|
|
*
|
|
* The location array should list the storage types to use in order of
|
|
* preference:
|
|
*
|
|
* ['flash']: flash only storage
|
|
* ['web']: web only storage
|
|
* ['both']: try to store in both
|
|
* ['flash','web']: store in flash first, but if not available, 'web'
|
|
* ['web','flash']: store in web first, but if not available, 'flash'
|
|
*
|
|
* The location array defaults to: ['web', 'flash']
|
|
*
|
|
* @param api the flash interface, null to use only WebStorage.
|
|
* @param id the storage ID to use.
|
|
* @param key the key for the item.
|
|
* @param data the data for the item (any javascript object/primitive).
|
|
* @param location an array with the preferred types of storage to use.
|
|
*/
|
|
util.setItem = function(api, id, key, data, location) {
|
|
_callStorageFunction(_setItem, arguments, location);
|
|
};
|
|
|
|
/**
|
|
* Gets an item on local disk.
|
|
*
|
|
* Set setItem() for details on storage types.
|
|
*
|
|
* @param api the flash interface, null to use only WebStorage.
|
|
* @param id the storage ID to use.
|
|
* @param key the key for the item.
|
|
* @param location an array with the preferred types of storage to use.
|
|
*
|
|
* @return the item.
|
|
*/
|
|
util.getItem = function(api, id, key, location) {
|
|
return _callStorageFunction(_getItem, arguments, location);
|
|
};
|
|
|
|
/**
|
|
* Removes an item on local disk.
|
|
*
|
|
* Set setItem() for details on storage types.
|
|
*
|
|
* @param api the flash interface.
|
|
* @param id the storage ID to use.
|
|
* @param key the key for the item.
|
|
* @param location an array with the preferred types of storage to use.
|
|
*/
|
|
util.removeItem = function(api, id, key, location) {
|
|
_callStorageFunction(_removeItem, arguments, location);
|
|
};
|
|
|
|
/**
|
|
* Clears the local disk storage identified by the given ID.
|
|
*
|
|
* Set setItem() for details on storage types.
|
|
*
|
|
* @param api the flash interface if flash is available.
|
|
* @param id the storage ID to use.
|
|
* @param location an array with the preferred types of storage to use.
|
|
*/
|
|
util.clearItems = function(api, id, location) {
|
|
_callStorageFunction(_clearItems, arguments, location);
|
|
};
|
|
|
|
/**
|
|
* Parses the scheme, host, and port from an http(s) url.
|
|
*
|
|
* @param str the url string.
|
|
*
|
|
* @return the parsed url object or null if the url is invalid.
|
|
*/
|
|
util.parseUrl = function(str) {
|
|
// FIXME: this regex looks a bit broken
|
|
var regex = /^(https?):\/\/([^:&^\/]*):?(\d*)(.*)$/g;
|
|
regex.lastIndex = 0;
|
|
var m = regex.exec(str);
|
|
var url = (m === null) ? null : {
|
|
full: str,
|
|
scheme: m[1],
|
|
host: m[2],
|
|
port: m[3],
|
|
path: m[4]
|
|
};
|
|
if(url) {
|
|
url.fullHost = url.host;
|
|
if(url.port) {
|
|
if(url.port !== 80 && url.scheme === 'http') {
|
|
url.fullHost += ':' + url.port;
|
|
} else if(url.port !== 443 && url.scheme === 'https') {
|
|
url.fullHost += ':' + url.port;
|
|
}
|
|
} else if(url.scheme === 'http') {
|
|
url.port = 80;
|
|
} else if(url.scheme === 'https') {
|
|
url.port = 443;
|
|
}
|
|
url.full = url.scheme + '://' + url.fullHost;
|
|
}
|
|
return url;
|
|
};
|
|
|
|
/* Storage for query variables */
|
|
var _queryVariables = null;
|
|
|
|
/**
|
|
* Returns the window location query variables. Query is parsed on the first
|
|
* call and the same object is returned on subsequent calls. The mapping
|
|
* is from keys to an array of values. Parameters without values will have
|
|
* an object key set but no value added to the value array. Values are
|
|
* unescaped.
|
|
*
|
|
* ...?k1=v1&k2=v2:
|
|
* {
|
|
* "k1": ["v1"],
|
|
* "k2": ["v2"]
|
|
* }
|
|
*
|
|
* ...?k1=v1&k1=v2:
|
|
* {
|
|
* "k1": ["v1", "v2"]
|
|
* }
|
|
*
|
|
* ...?k1=v1&k2:
|
|
* {
|
|
* "k1": ["v1"],
|
|
* "k2": []
|
|
* }
|
|
*
|
|
* ...?k1=v1&k1:
|
|
* {
|
|
* "k1": ["v1"]
|
|
* }
|
|
*
|
|
* ...?k1&k1:
|
|
* {
|
|
* "k1": []
|
|
* }
|
|
*
|
|
* @param query the query string to parse (optional, default to cached
|
|
* results from parsing window location search query).
|
|
*
|
|
* @return object mapping keys to variables.
|
|
*/
|
|
util.getQueryVariables = function(query) {
|
|
var parse = function(q) {
|
|
var rval = {};
|
|
var kvpairs = q.split('&');
|
|
for(var i = 0; i < kvpairs.length; i++) {
|
|
var pos = kvpairs[i].indexOf('=');
|
|
var key;
|
|
var val;
|
|
if(pos > 0) {
|
|
key = kvpairs[i].substring(0, pos);
|
|
val = kvpairs[i].substring(pos + 1);
|
|
} else {
|
|
key = kvpairs[i];
|
|
val = null;
|
|
}
|
|
if(!(key in rval)) {
|
|
rval[key] = [];
|
|
}
|
|
// disallow overriding object prototype keys
|
|
if(!(key in Object.prototype) && val !== null) {
|
|
rval[key].push(unescape(val));
|
|
}
|
|
}
|
|
return rval;
|
|
};
|
|
|
|
var rval;
|
|
if(typeof(query) === 'undefined') {
|
|
// set cached variables if needed
|
|
if(_queryVariables === null) {
|
|
if(typeof(window) !== 'undefined' && window.location && window.location.search) {
|
|
// parse window search query
|
|
_queryVariables = parse(window.location.search.substring(1));
|
|
} else {
|
|
// no query variables available
|
|
_queryVariables = {};
|
|
}
|
|
}
|
|
rval = _queryVariables;
|
|
} else {
|
|
// parse given query
|
|
rval = parse(query);
|
|
}
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Parses a fragment into a path and query. This method will take a URI
|
|
* fragment and break it up as if it were the main URI. For example:
|
|
* /bar/baz?a=1&b=2
|
|
* results in:
|
|
* {
|
|
* path: ["bar", "baz"],
|
|
* query: {"k1": ["v1"], "k2": ["v2"]}
|
|
* }
|
|
*
|
|
* @return object with a path array and query object.
|
|
*/
|
|
util.parseFragment = function(fragment) {
|
|
// default to whole fragment
|
|
var fp = fragment;
|
|
var fq = '';
|
|
// split into path and query if possible at the first '?'
|
|
var pos = fragment.indexOf('?');
|
|
if(pos > 0) {
|
|
fp = fragment.substring(0, pos);
|
|
fq = fragment.substring(pos + 1);
|
|
}
|
|
// split path based on '/' and ignore first element if empty
|
|
var path = fp.split('/');
|
|
if(path.length > 0 && path[0] === '') {
|
|
path.shift();
|
|
}
|
|
// convert query into object
|
|
var query = (fq === '') ? {} : util.getQueryVariables(fq);
|
|
|
|
return {
|
|
pathString: fp,
|
|
queryString: fq,
|
|
path: path,
|
|
query: query
|
|
};
|
|
};
|
|
|
|
/**
|
|
* Makes a request out of a URI-like request string. This is intended to
|
|
* be used where a fragment id (after a URI '#') is parsed as a URI with
|
|
* path and query parts. The string should have a path beginning and
|
|
* delimited by '/' and optional query parameters following a '?'. The
|
|
* query should be a standard URL set of key value pairs delimited by
|
|
* '&'. For backwards compatibility the initial '/' on the path is not
|
|
* required. The request object has the following API, (fully described
|
|
* in the method code):
|
|
* {
|
|
* path: <the path string part>.
|
|
* query: <the query string part>,
|
|
* getPath(i): get part or all of the split path array,
|
|
* getQuery(k, i): get part or all of a query key array,
|
|
* getQueryLast(k, _default): get last element of a query key array.
|
|
* }
|
|
*
|
|
* @return object with request parameters.
|
|
*/
|
|
util.makeRequest = function(reqString) {
|
|
var frag = util.parseFragment(reqString);
|
|
var req = {
|
|
// full path string
|
|
path: frag.pathString,
|
|
// full query string
|
|
query: frag.queryString,
|
|
/**
|
|
* Get path or element in path.
|
|
*
|
|
* @param i optional path index.
|
|
*
|
|
* @return path or part of path if i provided.
|
|
*/
|
|
getPath: function(i) {
|
|
return (typeof(i) === 'undefined') ? frag.path : frag.path[i];
|
|
},
|
|
/**
|
|
* Get query, values for a key, or value for a key index.
|
|
*
|
|
* @param k optional query key.
|
|
* @param i optional query key index.
|
|
*
|
|
* @return query, values for a key, or value for a key index.
|
|
*/
|
|
getQuery: function(k, i) {
|
|
var rval;
|
|
if(typeof(k) === 'undefined') {
|
|
rval = frag.query;
|
|
} else {
|
|
rval = frag.query[k];
|
|
if(rval && typeof(i) !== 'undefined') {
|
|
rval = rval[i];
|
|
}
|
|
}
|
|
return rval;
|
|
},
|
|
getQueryLast: function(k, _default) {
|
|
var rval;
|
|
var vals = req.getQuery(k);
|
|
if(vals) {
|
|
rval = vals[vals.length - 1];
|
|
} else {
|
|
rval = _default;
|
|
}
|
|
return rval;
|
|
}
|
|
};
|
|
return req;
|
|
};
|
|
|
|
/**
|
|
* Makes a URI out of a path, an object with query parameters, and a
|
|
* fragment. Uses jQuery.param() internally for query string creation.
|
|
* If the path is an array, it will be joined with '/'.
|
|
*
|
|
* @param path string path or array of strings.
|
|
* @param query object with query parameters. (optional)
|
|
* @param fragment fragment string. (optional)
|
|
*
|
|
* @return string object with request parameters.
|
|
*/
|
|
util.makeLink = function(path, query, fragment) {
|
|
// join path parts if needed
|
|
path = jQuery.isArray(path) ? path.join('/') : path;
|
|
|
|
var qstr = jQuery.param(query || {});
|
|
fragment = fragment || '';
|
|
return path +
|
|
((qstr.length > 0) ? ('?' + qstr) : '') +
|
|
((fragment.length > 0) ? ('#' + fragment) : '');
|
|
};
|
|
|
|
/**
|
|
* Check if an object is empty.
|
|
*
|
|
* Taken from:
|
|
* http://stackoverflow.com/questions/679915/how-do-i-test-for-an-empty-javascript-object-from-json/679937#679937
|
|
*
|
|
* @param object the object to check.
|
|
*/
|
|
util.isEmpty = function(obj) {
|
|
for(var prop in obj) {
|
|
if(obj.hasOwnProperty(prop)) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
};
|
|
|
|
/**
|
|
* Format with simple printf-style interpolation.
|
|
*
|
|
* %%: literal '%'
|
|
* %s,%o: convert next argument into a string.
|
|
*
|
|
* @param format the string to format.
|
|
* @param ... arguments to interpolate into the format string.
|
|
*/
|
|
util.format = function(format) {
|
|
var re = /%./g;
|
|
// current match
|
|
var match;
|
|
// current part
|
|
var part;
|
|
// current arg index
|
|
var argi = 0;
|
|
// collected parts to recombine later
|
|
var parts = [];
|
|
// last index found
|
|
var last = 0;
|
|
// loop while matches remain
|
|
while((match = re.exec(format))) {
|
|
part = format.substring(last, re.lastIndex - 2);
|
|
// don't add empty strings (ie, parts between %s%s)
|
|
if(part.length > 0) {
|
|
parts.push(part);
|
|
}
|
|
last = re.lastIndex;
|
|
// switch on % code
|
|
var code = match[0][1];
|
|
switch(code) {
|
|
case 's':
|
|
case 'o':
|
|
// check if enough arguments were given
|
|
if(argi < arguments.length) {
|
|
parts.push(arguments[argi++ + 1]);
|
|
} else {
|
|
parts.push('<?>');
|
|
}
|
|
break;
|
|
// FIXME: do proper formating for numbers, etc
|
|
//case 'f':
|
|
//case 'd':
|
|
case '%':
|
|
parts.push('%');
|
|
break;
|
|
default:
|
|
parts.push('<%' + code + '?>');
|
|
}
|
|
}
|
|
// add trailing part of format string
|
|
parts.push(format.substring(last));
|
|
return parts.join('');
|
|
};
|
|
|
|
/**
|
|
* Formats a number.
|
|
*
|
|
* http://snipplr.com/view/5945/javascript-numberformat--ported-from-php/
|
|
*/
|
|
util.formatNumber = function(number, decimals, dec_point, thousands_sep) {
|
|
// http://kevin.vanzonneveld.net
|
|
// + original by: Jonas Raoni Soares Silva (http://www.jsfromhell.com)
|
|
// + improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
|
|
// + bugfix by: Michael White (http://crestidg.com)
|
|
// + bugfix by: Benjamin Lupton
|
|
// + bugfix by: Allan Jensen (http://www.winternet.no)
|
|
// + revised by: Jonas Raoni Soares Silva (http://www.jsfromhell.com)
|
|
// * example 1: number_format(1234.5678, 2, '.', '');
|
|
// * returns 1: 1234.57
|
|
|
|
var n = number, c = isNaN(decimals = Math.abs(decimals)) ? 2 : decimals;
|
|
var d = dec_point === undefined ? ',' : dec_point;
|
|
var t = thousands_sep === undefined ?
|
|
'.' : thousands_sep, s = n < 0 ? '-' : '';
|
|
var i = parseInt((n = Math.abs(+n || 0).toFixed(c)), 10) + '';
|
|
var j = (i.length > 3) ? i.length % 3 : 0;
|
|
return s + (j ? i.substr(0, j) + t : '') +
|
|
i.substr(j).replace(/(\d{3})(?=\d)/g, '$1' + t) +
|
|
(c ? d + Math.abs(n - i).toFixed(c).slice(2) : '');
|
|
};
|
|
|
|
/**
|
|
* Formats a byte size.
|
|
*
|
|
* http://snipplr.com/view/5949/format-humanize-file-byte-size-presentation-in-javascript/
|
|
*/
|
|
util.formatSize = function(size) {
|
|
if(size >= 1073741824) {
|
|
size = util.formatNumber(size / 1073741824, 2, '.', '') + ' GiB';
|
|
} else if(size >= 1048576) {
|
|
size = util.formatNumber(size / 1048576, 2, '.', '') + ' MiB';
|
|
} else if(size >= 1024) {
|
|
size = util.formatNumber(size / 1024, 0) + ' KiB';
|
|
} else {
|
|
size = util.formatNumber(size, 0) + ' bytes';
|
|
}
|
|
return size;
|
|
};
|
|
|
|
/**
|
|
* Converts an IPv4 or IPv6 string representation into bytes (in network order).
|
|
*
|
|
* @param ip the IPv4 or IPv6 address to convert.
|
|
*
|
|
* @return the 4-byte IPv6 or 16-byte IPv6 address or null if the address can't
|
|
* be parsed.
|
|
*/
|
|
util.bytesFromIP = function(ip) {
|
|
if(ip.indexOf('.') !== -1) {
|
|
return util.bytesFromIPv4(ip);
|
|
}
|
|
if(ip.indexOf(':') !== -1) {
|
|
return util.bytesFromIPv6(ip);
|
|
}
|
|
return null;
|
|
};
|
|
|
|
/**
|
|
* Converts an IPv4 string representation into bytes (in network order).
|
|
*
|
|
* @param ip the IPv4 address to convert.
|
|
*
|
|
* @return the 4-byte address or null if the address can't be parsed.
|
|
*/
|
|
util.bytesFromIPv4 = function(ip) {
|
|
ip = ip.split('.');
|
|
if(ip.length !== 4) {
|
|
return null;
|
|
}
|
|
var b = util.createBuffer();
|
|
for(var i = 0; i < ip.length; ++i) {
|
|
var num = parseInt(ip[i], 10);
|
|
if(isNaN(num)) {
|
|
return null;
|
|
}
|
|
b.putByte(num);
|
|
}
|
|
return b.getBytes();
|
|
};
|
|
|
|
/**
|
|
* Converts an IPv6 string representation into bytes (in network order).
|
|
*
|
|
* @param ip the IPv6 address to convert.
|
|
*
|
|
* @return the 16-byte address or null if the address can't be parsed.
|
|
*/
|
|
util.bytesFromIPv6 = function(ip) {
|
|
var blanks = 0;
|
|
ip = ip.split(':').filter(function(e) {
|
|
if(e.length === 0) ++blanks;
|
|
return true;
|
|
});
|
|
var zeros = (8 - ip.length + blanks) * 2;
|
|
var b = util.createBuffer();
|
|
for(var i = 0; i < 8; ++i) {
|
|
if(!ip[i] || ip[i].length === 0) {
|
|
b.fillWithByte(0, zeros);
|
|
zeros = 0;
|
|
continue;
|
|
}
|
|
var bytes = util.hexToBytes(ip[i]);
|
|
if(bytes.length < 2) {
|
|
b.putByte(0);
|
|
}
|
|
b.putBytes(bytes);
|
|
}
|
|
return b.getBytes();
|
|
};
|
|
|
|
/**
|
|
* Converts 4-bytes into an IPv4 string representation or 16-bytes into
|
|
* an IPv6 string representation. The bytes must be in network order.
|
|
*
|
|
* @param bytes the bytes to convert.
|
|
*
|
|
* @return the IPv4 or IPv6 string representation if 4 or 16 bytes,
|
|
* respectively, are given, otherwise null.
|
|
*/
|
|
util.bytesToIP = function(bytes) {
|
|
if(bytes.length === 4) {
|
|
return util.bytesToIPv4(bytes);
|
|
}
|
|
if(bytes.length === 16) {
|
|
return util.bytesToIPv6(bytes);
|
|
}
|
|
return null;
|
|
};
|
|
|
|
/**
|
|
* Converts 4-bytes into an IPv4 string representation. The bytes must be
|
|
* in network order.
|
|
*
|
|
* @param bytes the bytes to convert.
|
|
*
|
|
* @return the IPv4 string representation or null for an invalid # of bytes.
|
|
*/
|
|
util.bytesToIPv4 = function(bytes) {
|
|
if(bytes.length !== 4) {
|
|
return null;
|
|
}
|
|
var ip = [];
|
|
for(var i = 0; i < bytes.length; ++i) {
|
|
ip.push(bytes.charCodeAt(i));
|
|
}
|
|
return ip.join('.');
|
|
};
|
|
|
|
/**
|
|
* Converts 16-bytes into an IPv16 string representation. The bytes must be
|
|
* in network order.
|
|
*
|
|
* @param bytes the bytes to convert.
|
|
*
|
|
* @return the IPv16 string representation or null for an invalid # of bytes.
|
|
*/
|
|
util.bytesToIPv6 = function(bytes) {
|
|
if(bytes.length !== 16) {
|
|
return null;
|
|
}
|
|
var ip = [];
|
|
var zeroGroups = [];
|
|
var zeroMaxGroup = 0;
|
|
for(var i = 0; i < bytes.length; i += 2) {
|
|
var hex = util.bytesToHex(bytes[i] + bytes[i + 1]);
|
|
// canonicalize zero representation
|
|
while(hex[0] === '0' && hex !== '0') {
|
|
hex = hex.substr(1);
|
|
}
|
|
if(hex === '0') {
|
|
var last = zeroGroups[zeroGroups.length - 1];
|
|
var idx = ip.length;
|
|
if(!last || idx !== last.end + 1) {
|
|
zeroGroups.push({start: idx, end: idx});
|
|
} else {
|
|
last.end = idx;
|
|
if((last.end - last.start) >
|
|
(zeroGroups[zeroMaxGroup].end - zeroGroups[zeroMaxGroup].start)) {
|
|
zeroMaxGroup = zeroGroups.length - 1;
|
|
}
|
|
}
|
|
}
|
|
ip.push(hex);
|
|
}
|
|
if(zeroGroups.length > 0) {
|
|
var group = zeroGroups[zeroMaxGroup];
|
|
// only shorten group of length > 0
|
|
if(group.end - group.start > 0) {
|
|
ip.splice(group.start, group.end - group.start + 1, '');
|
|
if(group.start === 0) {
|
|
ip.unshift('');
|
|
}
|
|
if(group.end === 7) {
|
|
ip.push('');
|
|
}
|
|
}
|
|
}
|
|
return ip.join(':');
|
|
};
|
|
|
|
/**
|
|
* Estimates the number of processes that can be run concurrently. If
|
|
* creating Web Workers, keep in mind that the main JavaScript process needs
|
|
* its own core.
|
|
*
|
|
* @param options the options to use:
|
|
* update true to force an update (not use the cached value).
|
|
* @param callback(err, max) called once the operation completes.
|
|
*/
|
|
util.estimateCores = function(options, callback) {
|
|
if(typeof options === 'function') {
|
|
callback = options;
|
|
options = {};
|
|
}
|
|
options = options || {};
|
|
if('cores' in util && !options.update) {
|
|
return callback(null, util.cores);
|
|
}
|
|
if(typeof navigator !== 'undefined' &&
|
|
'hardwareConcurrency' in navigator &&
|
|
navigator.hardwareConcurrency > 0) {
|
|
util.cores = navigator.hardwareConcurrency;
|
|
return callback(null, util.cores);
|
|
}
|
|
if(typeof Worker === 'undefined') {
|
|
// workers not available
|
|
util.cores = 1;
|
|
return callback(null, util.cores);
|
|
}
|
|
if(typeof Blob === 'undefined') {
|
|
// can't estimate, default to 2
|
|
util.cores = 2;
|
|
return callback(null, util.cores);
|
|
}
|
|
|
|
// create worker concurrency estimation code as blob
|
|
var blobUrl = URL.createObjectURL(new Blob(['(',
|
|
function() {
|
|
self.addEventListener('message', function(e) {
|
|
// run worker for 4 ms
|
|
var st = Date.now();
|
|
var et = st + 4;
|
|
while(Date.now() < et);
|
|
self.postMessage({st: st, et: et});
|
|
});
|
|
}.toString(),
|
|
')()'], {type: 'application/javascript'}));
|
|
|
|
// take 5 samples using 16 workers
|
|
sample([], 5, 16);
|
|
|
|
function sample(max, samples, numWorkers) {
|
|
if(samples === 0) {
|
|
// get overlap average
|
|
var avg = Math.floor(max.reduce(function(avg, x) {
|
|
return avg + x;
|
|
}, 0) / max.length);
|
|
util.cores = Math.max(1, avg);
|
|
URL.revokeObjectURL(blobUrl);
|
|
return callback(null, util.cores);
|
|
}
|
|
map(numWorkers, function(err, results) {
|
|
max.push(reduce(numWorkers, results));
|
|
sample(max, samples - 1, numWorkers);
|
|
});
|
|
}
|
|
|
|
function map(numWorkers, callback) {
|
|
var workers = [];
|
|
var results = [];
|
|
for(var i = 0; i < numWorkers; ++i) {
|
|
var worker = new Worker(blobUrl);
|
|
worker.addEventListener('message', function(e) {
|
|
results.push(e.data);
|
|
if(results.length === numWorkers) {
|
|
for(var i = 0; i < numWorkers; ++i) {
|
|
workers[i].terminate();
|
|
}
|
|
callback(null, results);
|
|
}
|
|
});
|
|
workers.push(worker);
|
|
}
|
|
for(var i = 0; i < numWorkers; ++i) {
|
|
workers[i].postMessage(i);
|
|
}
|
|
}
|
|
|
|
function reduce(numWorkers, results) {
|
|
// find overlapping time windows
|
|
var overlaps = [];
|
|
for(var n = 0; n < numWorkers; ++n) {
|
|
var r1 = results[n];
|
|
var overlap = overlaps[n] = [];
|
|
for(var i = 0; i < numWorkers; ++i) {
|
|
if(n === i) {
|
|
continue;
|
|
}
|
|
var r2 = results[i];
|
|
if((r1.st > r2.st && r1.st < r2.et) ||
|
|
(r2.st > r1.st && r2.st < r1.et)) {
|
|
overlap.push(i);
|
|
}
|
|
}
|
|
}
|
|
// get maximum overlaps ... don't include overlapping worker itself
|
|
// as the main JS process was also being scheduled during the work and
|
|
// would have to be subtracted from the estimate anyway
|
|
return overlaps.reduce(function(max, overlap) {
|
|
return Math.max(max, overlap.length);
|
|
}, 0);
|
|
}
|
|
};
|