snapdrop/app/elements/p2p-network/binaryjs.html

<script>
	/*! binary.js build:0.2.2, development. Copyright(c) 2012 Eric Zhang <eric@ericzhang.com> MIT Licensed */
(function(exports){
/*! binarypack.js build:0.0.9, production. Copyright(c) 2012 Eric Zhang <eric@ericzhang.com> MIT Licensed */(function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
var BufferBuilder = require('./bufferbuilder').BufferBuilder;
var binaryFeatures = require('./bufferbuilder').binaryFeatures;

var BinaryPack = {
  unpack: function(data){
    var unpacker = new Unpacker(data);
    return unpacker.unpack();
  },
  pack: function(data){
    var packer = new Packer();
    packer.pack(data);
    var buffer = packer.getBuffer();
    return buffer;
  }
};

module.exports = BinaryPack;

function Unpacker (data){
  // Data is ArrayBuffer
  this.index = 0;
  this.dataBuffer = data;
  this.dataView = new Uint8Array(this.dataBuffer);
  this.length = this.dataBuffer.byteLength;
}

Unpacker.prototype.unpack = function(){
  var type = this.unpack_uint8();
  if (type < 0x80){
    var positive_fixnum = type;
    return positive_fixnum;
  } else if ((type ^ 0xe0) < 0x20){
    var negative_fixnum = (type ^ 0xe0) - 0x20;
    return negative_fixnum;
  }
  var size;
  if ((size = type ^ 0xa0) <= 0x0f){
    return this.unpack_raw(size);
  } else if ((size = type ^ 0xb0) <= 0x0f){
    return this.unpack_string(size);
  } else if ((size = type ^ 0x90) <= 0x0f){
    return this.unpack_array(size);
  } else if ((size = type ^ 0x80) <= 0x0f){
    return this.unpack_map(size);
  }
  switch(type){
    case 0xc0:
      return null;
    case 0xc1:
      return undefined;
    case 0xc2:
      return false;
    case 0xc3:
      return true;
    case 0xca:
      return this.unpack_float();
    case 0xcb:
      return this.unpack_double();
    case 0xcc:
      return this.unpack_uint8();
    case 0xcd:
      return this.unpack_uint16();
    case 0xce:
      return this.unpack_uint32();
    case 0xcf:
      return this.unpack_uint64();
    case 0xd0:
      return this.unpack_int8();
    case 0xd1:
      return this.unpack_int16();
    case 0xd2:
      return this.unpack_int32();
    case 0xd3:
      return this.unpack_int64();
    case 0xd4:
      return undefined;
    case 0xd5:
      return undefined;
    case 0xd6:
      return undefined;
    case 0xd7:
      return undefined;
    case 0xd8:
      size = this.unpack_uint16();
      return this.unpack_string(size);
    case 0xd9:
      size = this.unpack_uint32();
      return this.unpack_string(size);
    case 0xda:
      size = this.unpack_uint16();
      return this.unpack_raw(size);
    case 0xdb:
      size = this.unpack_uint32();
      return this.unpack_raw(size);
    case 0xdc:
      size = this.unpack_uint16();
      return this.unpack_array(size);
    case 0xdd:
      size = this.unpack_uint32();
      return this.unpack_array(size);
    case 0xde:
      size = this.unpack_uint16();
      return this.unpack_map(size);
    case 0xdf:
      size = this.unpack_uint32();
      return this.unpack_map(size);
  }
}

Unpacker.prototype.unpack_uint8 = function(){
  var byte = this.dataView[this.index] & 0xff;
  this.index++;
  return byte;
};

Unpacker.prototype.unpack_uint16 = function(){
  var bytes = this.read(2);
  var uint16 =
    ((bytes[0] & 0xff) * 256) + (bytes[1] & 0xff);
  this.index += 2;
  return uint16;
}

Unpacker.prototype.unpack_uint32 = function(){
  var bytes = this.read(4);
  var uint32 =
     ((bytes[0]  * 256 +
       bytes[1]) * 256 +
       bytes[2]) * 256 +
       bytes[3];
  this.index += 4;
  return uint32;
}

Unpacker.prototype.unpack_uint64 = function(){
  var bytes = this.read(8);
  var uint64 =
   ((((((bytes[0]  * 256 +
       bytes[1]) * 256 +
       bytes[2]) * 256 +
       bytes[3]) * 256 +
       bytes[4]) * 256 +
       bytes[5]) * 256 +
       bytes[6]) * 256 +
       bytes[7];
  this.index += 8;
  return uint64;
}


Unpacker.prototype.unpack_int8 = function(){
  var uint8 = this.unpack_uint8();
  return (uint8 < 0x80 ) ? uint8 : uint8 - (1 << 8);
};

Unpacker.prototype.unpack_int16 = function(){
  var uint16 = this.unpack_uint16();
  return (uint16 < 0x8000 ) ? uint16 : uint16 - (1 << 16);
}

Unpacker.prototype.unpack_int32 = function(){
  var uint32 = this.unpack_uint32();
  return (uint32 < Math.pow(2, 31) ) ? uint32 :
    uint32 - Math.pow(2, 32);
}

Unpacker.prototype.unpack_int64 = function(){
  var uint64 = this.unpack_uint64();
  return (uint64 < Math.pow(2, 63) ) ? uint64 :
    uint64 - Math.pow(2, 64);
}

Unpacker.prototype.unpack_raw = function(size){
  if ( this.length < this.index + size){
    throw new Error('BinaryPackFailure: index is out of range'
      + ' ' + this.index + ' ' + size + ' ' + this.length);
  }
  var buf = this.dataBuffer.slice(this.index, this.index + size);
  this.index += size;

    //buf = util.bufferToString(buf);

  return buf;
}

Unpacker.prototype.unpack_string = function(size){
  var bytes = this.read(size);
  var i = 0, str = '', c, code;
  while(i < size){
    c = bytes[i];
    if ( c < 128){
      str += String.fromCharCode(c);
      i++;
    } else if ((c ^ 0xc0) < 32){
      code = ((c ^ 0xc0) << 6) | (bytes[i+1] & 63);
      str += String.fromCharCode(code);
      i += 2;
    } else {
      code = ((c & 15) << 12) | ((bytes[i+1] & 63) << 6) |
        (bytes[i+2] & 63);
      str += String.fromCharCode(code);
      i += 3;
    }
  }
  this.index += size;
  return str;
}

Unpacker.prototype.unpack_array = function(size){
  var objects = new Array(size);
  for(var i = 0; i < size ; i++){
    objects[i] = this.unpack();
  }
  return objects;
}

Unpacker.prototype.unpack_map = function(size){
  var map = {};
  for(var i = 0; i < size ; i++){
    var key  = this.unpack();
    var value = this.unpack();
    map[key] = value;
  }
  return map;
}

Unpacker.prototype.unpack_float = function(){
  var uint32 = this.unpack_uint32();
  var sign = uint32 >> 31;
  var exp  = ((uint32 >> 23) & 0xff) - 127;
  var fraction = ( uint32 & 0x7fffff ) | 0x800000;
  return (sign == 0 ? 1 : -1) *
    fraction * Math.pow(2, exp - 23);
}

Unpacker.prototype.unpack_double = function(){
  var h32 = this.unpack_uint32();
  var l32 = this.unpack_uint32();
  var sign = h32 >> 31;
  var exp  = ((h32 >> 20) & 0x7ff) - 1023;
  var hfrac = ( h32 & 0xfffff ) | 0x100000;
  var frac = hfrac * Math.pow(2, exp - 20) +
    l32   * Math.pow(2, exp - 52);
  return (sign == 0 ? 1 : -1) * frac;
}

Unpacker.prototype.read = function(length){
  var j = this.index;
  if (j + length <= this.length) {
    return this.dataView.subarray(j, j + length);
  } else {
    throw new Error('BinaryPackFailure: read index out of range');
  }
}

function Packer(){
  this.bufferBuilder = new BufferBuilder();
}

Packer.prototype.getBuffer = function(){
  return this.bufferBuilder.getBuffer();
}

Packer.prototype.pack = function(value){
  var type = typeof(value);
  if (type == 'string'){
    this.pack_string(value);
  } else if (type == 'number'){
    if (Math.floor(value) === value){
      this.pack_integer(value);
    } else{
      this.pack_double(value);
    }
  } else if (type == 'boolean'){
    if (value === true){
      this.bufferBuilder.append(0xc3);
    } else if (value === false){
      this.bufferBuilder.append(0xc2);
    }
  } else if (type == 'undefined'){
    this.bufferBuilder.append(0xc0);
  } else if (type == 'object'){
    if (value === null){
      this.bufferBuilder.append(0xc0);
    } else {
      var constructor = value.constructor;
      if (constructor == Array){
        this.pack_array(value);
      } else if (constructor == Blob || constructor == File) {
        this.pack_bin(value);
      } else if (constructor == ArrayBuffer) {
        if(binaryFeatures.useArrayBufferView) {
          this.pack_bin(new Uint8Array(value));
        } else {
          this.pack_bin(value);
        }
      } else if ('BYTES_PER_ELEMENT' in value){
        if(binaryFeatures.useArrayBufferView) {
          this.pack_bin(new Uint8Array(value.buffer));
        } else {
          this.pack_bin(value.buffer);
        }
      } else if (constructor == Object){
        this.pack_object(value);
      } else if (constructor == Date){
        this.pack_string(value.toString());
      } else if (typeof value.toBinaryPack == 'function'){
        this.bufferBuilder.append(value.toBinaryPack());
      } else {
        throw new Error('Type "' + constructor.toString() + '" not yet supported');
      }
    }
  } else {
    throw new Error('Type "' + type + '" not yet supported');
  }
  this.bufferBuilder.flush();
}


Packer.prototype.pack_bin = function(blob){
  var length = blob.length || blob.byteLength || blob.size;
  if (length <= 0x0f){
    this.pack_uint8(0xa0 + length);
  } else if (length <= 0xffff){
    this.bufferBuilder.append(0xda) ;
    this.pack_uint16(length);
  } else if (length <= 0xffffffff){
    this.bufferBuilder.append(0xdb);
    this.pack_uint32(length);
  } else{
    throw new Error('Invalid length');
  }
  this.bufferBuilder.append(blob);
}

Packer.prototype.pack_string = function(str){
  var length = utf8Length(str);

  if (length <= 0x0f){
    this.pack_uint8(0xb0 + length);
  } else if (length <= 0xffff){
    this.bufferBuilder.append(0xd8) ;
    this.pack_uint16(length);
  } else if (length <= 0xffffffff){
    this.bufferBuilder.append(0xd9);
    this.pack_uint32(length);
  } else{
    throw new Error('Invalid length');
  }
  this.bufferBuilder.append(str);
}

Packer.prototype.pack_array = function(ary){
  var length = ary.length;
  if (length <= 0x0f){
    this.pack_uint8(0x90 + length);
  } else if (length <= 0xffff){
    this.bufferBuilder.append(0xdc)
    this.pack_uint16(length);
  } else if (length <= 0xffffffff){
    this.bufferBuilder.append(0xdd);
    this.pack_uint32(length);
  } else{
    throw new Error('Invalid length');
  }
  for(var i = 0; i < length ; i++){
    this.pack(ary[i]);
  }
}

Packer.prototype.pack_integer = function(num){
  if ( -0x20 <= num && num <= 0x7f){
    this.bufferBuilder.append(num & 0xff);
  } else if (0x00 <= num && num <= 0xff){
    this.bufferBuilder.append(0xcc);
    this.pack_uint8(num);
  } else if (-0x80 <= num && num <= 0x7f){
    this.bufferBuilder.append(0xd0);
    this.pack_int8(num);
  } else if ( 0x0000 <= num && num <= 0xffff){
    this.bufferBuilder.append(0xcd);
    this.pack_uint16(num);
  } else if (-0x8000 <= num && num <= 0x7fff){
    this.bufferBuilder.append(0xd1);
    this.pack_int16(num);
  } else if ( 0x00000000 <= num && num <= 0xffffffff){
    this.bufferBuilder.append(0xce);
    this.pack_uint32(num);
  } else if (-0x80000000 <= num && num <= 0x7fffffff){
    this.bufferBuilder.append(0xd2);
    this.pack_int32(num);
  } else if (-0x8000000000000000 <= num && num <= 0x7FFFFFFFFFFFFFFF){
    this.bufferBuilder.append(0xd3);
    this.pack_int64(num);
  } else if (0x0000000000000000 <= num && num <= 0xFFFFFFFFFFFFFFFF){
    this.bufferBuilder.append(0xcf);
    this.pack_uint64(num);
  } else{
    throw new Error('Invalid integer');
  }
}

Packer.prototype.pack_double = function(num){
  var sign = 0;
  if (num < 0){
    sign = 1;
    num = -num;
  }
  var exp  = Math.floor(Math.log(num) / Math.LN2);
  var frac0 = num / Math.pow(2, exp) - 1;
  var frac1 = Math.floor(frac0 * Math.pow(2, 52));
  var b32   = Math.pow(2, 32);
  var h32 = (sign << 31) | ((exp+1023) << 20) |
      (frac1 / b32) & 0x0fffff;
  var l32 = frac1 % b32;
  this.bufferBuilder.append(0xcb);
  this.pack_int32(h32);
  this.pack_int32(l32);
}

Packer.prototype.pack_object = function(obj){
  var keys = Object.keys(obj);
  var length = keys.length;
  if (length <= 0x0f){
    this.pack_uint8(0x80 + length);
  } else if (length <= 0xffff){
    this.bufferBuilder.append(0xde);
    this.pack_uint16(length);
  } else if (length <= 0xffffffff){
    this.bufferBuilder.append(0xdf);
    this.pack_uint32(length);
  } else{
    throw new Error('Invalid length');
  }
  for(var prop in obj){
    if (obj.hasOwnProperty(prop)){
      this.pack(prop);
      this.pack(obj[prop]);
    }
  }
}

Packer.prototype.pack_uint8 = function(num){
  this.bufferBuilder.append(num);
}

Packer.prototype.pack_uint16 = function(num){
  this.bufferBuilder.append(num >> 8);
  this.bufferBuilder.append(num & 0xff);
}

Packer.prototype.pack_uint32 = function(num){
  var n = num & 0xffffffff;
  this.bufferBuilder.append((n & 0xff000000) >>> 24);
  this.bufferBuilder.append((n & 0x00ff0000) >>> 16);
  this.bufferBuilder.append((n & 0x0000ff00) >>>  8);
  this.bufferBuilder.append((n & 0x000000ff));
}

Packer.prototype.pack_uint64 = function(num){
  var high = num / Math.pow(2, 32);
  var low  = num % Math.pow(2, 32);
  this.bufferBuilder.append((high & 0xff000000) >>> 24);
  this.bufferBuilder.append((high & 0x00ff0000) >>> 16);
  this.bufferBuilder.append((high & 0x0000ff00) >>>  8);
  this.bufferBuilder.append((high & 0x000000ff));
  this.bufferBuilder.append((low  & 0xff000000) >>> 24);
  this.bufferBuilder.append((low  & 0x00ff0000) >>> 16);
  this.bufferBuilder.append((low  & 0x0000ff00) >>>  8);
  this.bufferBuilder.append((low  & 0x000000ff));
}

Packer.prototype.pack_int8 = function(num){
  this.bufferBuilder.append(num & 0xff);
}

Packer.prototype.pack_int16 = function(num){
  this.bufferBuilder.append((num & 0xff00) >> 8);
  this.bufferBuilder.append(num & 0xff);
}

Packer.prototype.pack_int32 = function(num){
  this.bufferBuilder.append((num >>> 24) & 0xff);
  this.bufferBuilder.append((num & 0x00ff0000) >>> 16);
  this.bufferBuilder.append((num & 0x0000ff00) >>> 8);
  this.bufferBuilder.append((num & 0x000000ff));
}

Packer.prototype.pack_int64 = function(num){
  var high = Math.floor(num / Math.pow(2, 32));
  var low  = num % Math.pow(2, 32);
  this.bufferBuilder.append((high & 0xff000000) >>> 24);
  this.bufferBuilder.append((high & 0x00ff0000) >>> 16);
  this.bufferBuilder.append((high & 0x0000ff00) >>>  8);
  this.bufferBuilder.append((high & 0x000000ff));
  this.bufferBuilder.append((low  & 0xff000000) >>> 24);
  this.bufferBuilder.append((low  & 0x00ff0000) >>> 16);
  this.bufferBuilder.append((low  & 0x0000ff00) >>>  8);
  this.bufferBuilder.append((low  & 0x000000ff));
}

function _utf8Replace(m){
  var code = m.charCodeAt(0);

  if(code <= 0x7ff) return '00';
  if(code <= 0xffff) return '000';
  if(code <= 0x1fffff) return '0000';
  if(code <= 0x3ffffff) return '00000';
  return '000000';
}

function utf8Length(str){
  if (str.length > 600) {
    // Blob method faster for large strings
    return (new Blob([str])).size;
  } else {
    return str.replace(/[^\u0000-\u007F]/g, _utf8Replace).length;
  }
}

},{"./bufferbuilder":2}],2:[function(require,module,exports){
var binaryFeatures = {};
binaryFeatures.useBlobBuilder = (function(){
  try {
    new Blob([]);
    return false;
  } catch (e) {
    return true;
  }
})();

binaryFeatures.useArrayBufferView = !binaryFeatures.useBlobBuilder && (function(){
  try {
    return (new Blob([new Uint8Array([])])).size === 0;
  } catch (e) {
    return true;
  }
})();

module.exports.binaryFeatures = binaryFeatures;
var BlobBuilder = module.exports.BlobBuilder;
if (typeof window != 'undefined') {
  BlobBuilder = module.exports.BlobBuilder = window.WebKitBlobBuilder ||
    window.MozBlobBuilder || window.MSBlobBuilder || window.BlobBuilder;
}

function BufferBuilder(){
  this._pieces = [];
  this._parts = [];
}

BufferBuilder.prototype.append = function(data) {
  if(typeof data === 'number') {
    this._pieces.push(data);
  } else {
    this.flush();
    this._parts.push(data);
  }
};

BufferBuilder.prototype.flush = function() {
  if (this._pieces.length > 0) {
    var buf = new Uint8Array(this._pieces);
    if(!binaryFeatures.useArrayBufferView) {
      buf = buf.buffer;
    }
    this._parts.push(buf);
    this._pieces = [];
  }
};

BufferBuilder.prototype.getBuffer = function() {
  this.flush();
  if(binaryFeatures.useBlobBuilder) {
    var builder = new BlobBuilder();
    for(var i = 0, ii = this._parts.length; i < ii; i++) {
      builder.append(this._parts[i]);
    }
    return builder.getBlob();
  } else {
    return new Blob(this._parts);
  }
};

module.exports.BufferBuilder = BufferBuilder;

},{}],3:[function(require,module,exports){
var BufferBuilderExports = require('./bufferbuilder');

window.BufferBuilder = BufferBuilderExports.BufferBuilder;
window.binaryFeatures = BufferBuilderExports.binaryFeatures;
window.BlobBuilder = BufferBuilderExports.BlobBuilder;
window.BinaryPack = require('./binarypack');

},{"./binarypack":1,"./bufferbuilder":2}]},{},[3]);
/**
 * Light EventEmitter. Ported from Node.js/events.js
 * Eric Zhang
 */

/**
 * EventEmitter class
 * Creates an object with event registering and firing methods
 */
function EventEmitter() {
  // Initialise required storage variables
  this._events = {};
}

var isArray = Array.isArray;


EventEmitter.prototype.addListener = function(type, listener, scope, once) {
  if ('function' !== typeof listener) {
    throw new Error('addListener only takes instances of Function');
  }
  
  // To avoid recursion in the case that type == "newListeners"! Before
  // adding it to the listeners, first emit "newListeners".
  this.emit('newListener', type, typeof listener.listener === 'function' ?
            listener.listener : listener);
            
  if (!this._events[type]) {
    // Optimize the case of one listener. Don't need the extra array object.
    this._events[type] = listener;
  } else if (isArray(this._events[type])) {

    // If we've already got an array, just append.
    this._events[type].push(listener);

  } else {
    // Adding the second element, need to change to array.
    this._events[type] = [this._events[type], listener];
  }
  
};

EventEmitter.prototype.on = EventEmitter.prototype.addListener;

EventEmitter.prototype.once = function(type, listener, scope) {
  if ('function' !== typeof listener) {
    throw new Error('.once only takes instances of Function');
  }

  var self = this;
  function g() {
    self.removeListener(type, g);
    listener.apply(this, arguments);
  };

  g.listener = listener;
  self.on(type, g);

  return this;
};

EventEmitter.prototype.removeListener = function(type, listener, scope) {
  if ('function' !== typeof listener) {
    throw new Error('removeListener only takes instances of Function');
  }

  // does not use listeners(), so no side effect of creating _events[type]
  if (!this._events[type]) return this;

  var list = this._events[type];

  if (isArray(list)) {
    var position = -1;
    for (var i = 0, length = list.length; i < length; i++) {
      if (list[i] === listener ||
          (list[i].listener && list[i].listener === listener))
      {
        position = i;
        break;
      }
    }

    if (position < 0) return this;
    list.splice(position, 1);
    if (list.length == 0)
      delete this._events[type];
  } else if (list === listener ||
             (list.listener && list.listener === listener))
  {
    delete this._events[type];
  }

  return this;
};


EventEmitter.prototype.off = EventEmitter.prototype.removeListener;


EventEmitter.prototype.removeAllListeners = function(type) {
  if (arguments.length === 0) {
    this._events = {};
    return this;
  }

  // does not use listeners(), so no side effect of creating _events[type]
  if (type && this._events && this._events[type]) this._events[type] = null;
  return this;
};

EventEmitter.prototype.listeners = function(type) {
  if (!this._events[type]) this._events[type] = [];
  if (!isArray(this._events[type])) {
    this._events[type] = [this._events[type]];
  }
  return this._events[type];
};

EventEmitter.prototype.emit = function(type) {
  var type = arguments[0];
  var handler = this._events[type];
  if (!handler) return false;

  if (typeof handler == 'function') {
    switch (arguments.length) {
      // fast cases
      case 1:
        handler.call(this);
        break;
      case 2:
        handler.call(this, arguments[1]);
        break;
      case 3:
        handler.call(this, arguments[1], arguments[2]);
        break;
      // slower
      default:
        var l = arguments.length;
        var args = new Array(l - 1);
        for (var i = 1; i < l; i++) args[i - 1] = arguments[i];
        handler.apply(this, args);
    }
    return true;

  } else if (isArray(handler)) {
    var l = arguments.length;
    var args = new Array(l - 1);
    for (var i = 1; i < l; i++) args[i - 1] = arguments[i];

    var listeners = handler.slice();
    for (var i = 0, l = listeners.length; i < l; i++) {
      listeners[i].apply(this, args);
    }
    return true;
  } else {
    return false;
  }
};




var util = {
  inherits: function(ctor, superCtor) {
    ctor.super_ = superCtor;
    ctor.prototype = Object.create(superCtor.prototype, {
      constructor: {
        value: ctor,
        enumerable: false,
        writable: true,
        configurable: true
      }
    });
  },
  extend: function(dest, source) {
    for(var key in source) {
      if(source.hasOwnProperty(key)) {
        dest[key] = source[key];
      }
    }
    return dest;
  },
  pack: BinaryPack.pack,
  unpack: BinaryPack.unpack,
  setZeroTimeout: (function(global) {
    var timeouts = [];
    var messageName = 'zero-timeout-message';

    // Like setTimeout, but only takes a function argument.	 There's
    // no time argument (always zero) and no arguments (you have to
    // use a closure).
    function setZeroTimeoutPostMessage(fn) {
      timeouts.push(fn);
      global.postMessage(messageName, '*');
    }		

    function handleMessage(event) {
      if (event.source == global && event.data == messageName) {
        if (event.stopPropagation) {
          event.stopPropagation();
        }
        if (timeouts.length) {
          timeouts.shift()();
        }
      }
    }
    if (global.addEventListener) {
      global.addEventListener('message', handleMessage, true);
    } else if (global.attachEvent) {
      global.attachEvent('onmessage', handleMessage);
    }
    return setZeroTimeoutPostMessage;
  }(this))
};

exports.util = util;


function Stream() {
  EventEmitter.call(this);
}

util.inherits(Stream, EventEmitter);

Stream.prototype.pipe = function(dest, options) {
  var source = this;

  function ondata(chunk) {
    if (dest.writable) {
      if (false === dest.write(chunk) && source.pause) {
        source.pause();
      }
    }
  }

  source.on('data', ondata);

  function ondrain() {
    if (source.readable && source.resume) {
      source.resume();
    }
  }

  dest.on('drain', ondrain);

  // If the 'end' option is not supplied, dest.end() will be called when
  // source gets the 'end' or 'close' events.  Only dest.end() once.
  if (!dest._isStdio && (!options || options.end !== false)) {
    source.on('end', onend);
    source.on('close', onclose);
  }

  var didOnEnd = false;
  function onend() {
    if (didOnEnd) return;
    didOnEnd = true;

    dest.end();
  }


  function onclose() {
    if (didOnEnd) return;
    didOnEnd = true;

    dest.destroy();
  }

  // don't leave dangling pipes when there are errors.
  function onerror(er) {
    cleanup();
    if (this.listeners('error').length === 0) {
      throw er; // Unhandled stream error in pipe.
    }
  }

  source.on('error', onerror);
  dest.on('error', onerror);

  // remove all the event listeners that were added.
  function cleanup() {
    source.removeListener('data', ondata);
    dest.removeListener('drain', ondrain);

    source.removeListener('end', onend);
    source.removeListener('close', onclose);

    source.removeListener('error', onerror);
    dest.removeListener('error', onerror);

    source.removeListener('end', cleanup);
    source.removeListener('close', cleanup);

    dest.removeListener('end', cleanup);
    dest.removeListener('close', cleanup);
  }

  source.on('end', cleanup);
  source.on('close', cleanup);

  dest.on('end', cleanup);
  dest.on('close', cleanup);

  dest.emit('pipe', source);

  // Allow for unix-like usage: A.pipe(B).pipe(C)
  return dest;
};

exports.Stream = Stream;
function BlobReadStream(source, options){
  Stream.call(this);
  
  options = util.extend({
      readDelay: 0,
      paused: false
  }, options);
  
  this._source = source;
  this._start = 0;
  this._readChunkSize = options.chunkSize || source.size;
  this._readDelay = options.readDelay;
  
  this.readable = true;
  this.paused = options.paused;
  
  this._read();
}

util.inherits(BlobReadStream, Stream);


BlobReadStream.prototype.pause = function(){
  this.paused = true;
};

BlobReadStream.prototype.resume = function(){
  this.paused = false;
  this._read();
};

BlobReadStream.prototype.destroy = function(){
  this.readable = false;
  clearTimeout(this._timeoutId);
};

BlobReadStream.prototype._read = function(){
    
  var self = this;
  
  function emitReadChunk(){
    self._emitReadChunk();
  }
  
  var readDelay = this._readDelay;
  if (readDelay !== 0){
    this._timeoutId = setTimeout(emitReadChunk, readDelay);
  } else {
    util.setZeroTimeout(emitReadChunk);
  }
    
};

BlobReadStream.prototype._emitReadChunk = function(){
    
  if(this.paused || !this.readable) return;
  
  var chunkSize = Math.min(this._source.size - this._start, this._readChunkSize);
  
  if(chunkSize === 0){
      this.readable = false;
      this.emit("end");
      return;
  }
  
  var sourceEnd = this._start + chunkSize;
  var chunk = (this._source.slice || this._source.webkitSlice || this._source.mozSlice).call(this._source, this._start, sourceEnd);
  
  this._start = sourceEnd;
  this._read();
  
  this.emit("data", chunk);
  
};

/*




function BlobWriteStream(options){
    
    stream.Stream.call(this);
    
    options = _.extend({
        onFull: onFull,
        onEnd: function(){},
        minBlockAllocSize: 0,
        drainDelay:0
    }, options);
    
    this._onFull = options.onFull;
    this._onEnd = options.onEnd;
    this._onWrite = options.onWrite;
    
    this._minBlockAllocSize = options.minBlockAllocSize;
    this._maxBlockAllocSize = options.maxBlockAllocSize;
    this._drainDelay = options.drainDelay;
    
    this._buffer = new Buffer(options.minBlockAllocSize);
    this._destination = this._buffer;
    this._destinationPos = 0;
    
    this._writeQueue = [];
    this._pendingOnFull = false;
    this._pendingQueueDrain = false;
    
    this.writable = true;
    this.bytesWritten = 0;
}

util.inherits(BlobWriteStream, stream.Stream);

BlobWriteStream.prototype.getBuffer = function(){
    return this._buffer;
};

BlobWriteStream.prototype.write = function(data, encoding){
    
    if(!this.writable){
        throw new Error("stream is not writable");
    }
    
    if(!Buffer.isBuffer(data)){
        data = new Buffer(data, encoding);
    }
    
    if(data.length){
        this._writeQueue.push(data);
    }
    
    this._commit();
    
    return this._writeQueue.length === 0;
};

BlobWriteStream.prototype._commit = function(){
    
    var self = this;
    
    var destination = this._destination;
    var writeQueue = this._writeQueue;
    
    var startDestinationPos = this._destinationPos;
    
    while(writeQueue.length && destination.length){
        
        var head = writeQueue[0];
        
        var copySize = Math.min(destination.length, head.length);
        
        head.copy(destination, 0, 0, copySize);
        
        head = head.slice(copySize);
        destination = destination.slice(copySize);
        
        this.bytesWritten += copySize;
        this._destinationPos += copySize;
        
        if(head.length === 0){
            writeQueue.shift();
        }
        else{
            writeQueue[0] = head;
        }
    }
    
    this._destination = destination;
    
    bytesCommitted = this._destinationPos - startDestinationPos;
    if(bytesCommitted){
        if(this._onWrite){
            
            if(writeQueue.length){
                this._pendingQueueDrain = true;
            }
            
            // By locking destination the buffer is frozen and the onWrite
            // callback cannot miss any write commits
            this._destination = emptyBuffer;
            
            var consumer = this._onWrite;
            this._onWrite = null;
            
            consumer.call(this, function(nextCallback){
                util.setZeroTimeout(function(){
                    self._destination = destination;
                    self._onWrite = nextCallback;
                    self._commit();
                });
            }, consumer);
            
            return;
        }
    }
    
    if(writeQueue.length){
        
        this._pendingQueueDrain = true;
        this._growBuffer();
    }
    else if(this._pendingQueueDrain){
        
        this._pendingQueueDrain = false;
        
        if(this._drainDelay !== 0){
            setTimeout(function(){
                self.emit("drain");
            }, this._drainDelay);
        }
        else{
            util.setZeroTimeout(function(){
                self.emit("drain");
            });
        }
    }
};

BlobWriteStream.prototype._growBuffer = function(){
    
    var self = this;
    var writeQueue = this._writeQueue;
    
    var requestSize = this._minBlockAllocSize;
    
    var maxBlockAllocSize = this._maxBlockAllocSize;
    var add = (maxBlockAllocSize === undefined ? function(a, b){return a + b;} : function(a, b){return Math.min(a + b, maxBlockAllocSize);});
    
    for(var i = 0, queueLength = writeQueue.length; i < queueLength; i++){
        requestSize = add(requestSize, writeQueue[i].length);
    }
    
    // Prevent concurrent onFull callbacks
    if(this._pendingOnFull){
        return;
    }
    this._pendingOnFull = true;
    
    this._onFull(this._buffer, requestSize, function(buffer, destination){
        util.setZeroTimeout(function(){
            
            self._pendingOnFull = false;
            
            if(!destination){
                if(self.writable){
                    self.emit("error", new Error("buffer is full"));
                }
                self.destroy();
                return;
            }
            
            self._buffer = buffer;
            self._destination = destination;
            
            self._commit();
        });
    });
};

BlobWriteStream.prototype.end = function(data, encoding){
    
    var self = this;
    
    function _end(){
        self.writable = false;
        self._onEnd();
    }
    
    if(data){
        if(this.write(data, encoding)){
            _end();
        }else{
            self.writable = false;
            this.once("drain", _end);
        }
    }
    else{
        _end();
    }
};

BlobWriteStream.prototype.destroy = function(){
    this.writable = false;
    this._pendingQueueDrain = false;
    this._writeQueue = [];
};

BlobWriteStream.prototype.consume = function(consume){
    
    this._buffer = this._buffer.slice(consume);
    this._destinationPos -= consume;
};

BlobWriteStream.prototype.getCommittedSlice = function(){
    return this._buffer.slice(0, this._destinationPos);
};

function onFull(buffer, extraSize, callback){
    var newBuffer = new Buffer(buffer.length + extraSize);
    buffer.copy(newBuffer);
    callback(newBuffer, newBuffer.slice(buffer.length));
}
*/
exports.BlobReadStream = BlobReadStream;

function BinaryStream(socket, id, create, meta) {
  if (!(this instanceof BinaryStream)) return new BinaryStream(options);
  
  var self = this;
  
  Stream.call(this);

  
  this.id = id;
  this._socket = socket;
    
  this.writable = true;
  this.readable = true;
  this.paused = false;
  
  this._closed = false;
  this._ended = false;
  
  if(create) {
    // This is a stream we are creating
    this._write(1, meta, this.id);
  }
}

util.inherits(BinaryStream, Stream);


BinaryStream.prototype._onDrain = function() {
  if(!this.paused) {
    this.emit('drain');
  }
};

BinaryStream.prototype._onClose = function() {
  // Emit close event
  if (this._closed) {
    return;
  }
  this.readable = false;
  this.writable = false;
  this._closed = true;
  this.emit('close');
};

BinaryStream.prototype._onError = function(error){
  this.readable = false;
  this.writable = false;
  this.emit('error', error);
};

// Write stream

BinaryStream.prototype._onPause = function() {
  // Emit pause event
  this.paused = true;
  this.emit('pause');
};

BinaryStream.prototype._onResume = function() {
  // Emit resume event
  this.paused = false;
  this.emit('resume');
  this.emit('drain');
};

BinaryStream.prototype._write = function(code, data, bonus) {
  if (this._socket.readyState !== this._socket.constructor.OPEN) {
    return false;
  }
  var message = util.pack([code, data, bonus]);
  return this._socket.send(message) !== false;
};

BinaryStream.prototype.write = function(data) {
  if(this.writable) {
    var out = this._write(2, data, this.id);
    return !this.paused && out;
  } else {
    this.emit('error', new Error('Stream is not writable'));
    return false;
  }
};

BinaryStream.prototype.end = function() {
  this._ended = true;
  this.readable = false;
  this._write(5, null, this.id);
};

BinaryStream.prototype.destroy = BinaryStream.prototype.destroySoon = function() {
  this._onClose();
  this._write(6, null, this.id);
};


// Read stream

BinaryStream.prototype._onEnd = function() {
  if(this._ended) { 
    return;
  }
  this._ended = true;
  this.readable = false;
  this.emit('end');
};

BinaryStream.prototype._onData = function(data) {
  // Dispatch 
  this.emit('data', data);
};

BinaryStream.prototype.pause = function() {
  this._onPause();
  this._write(3, null, this.id);
};

BinaryStream.prototype.resume = function() {
  this._onResume();
  this._write(4, null, this.id);
};


function BinaryClient(socket, options) {
  if (!(this instanceof BinaryClient)) return new BinaryClient(socket, options);
  
  EventEmitter.call(this);
  
  var self = this;
  
  this._options = util.extend({
    chunkSize: 40960
  }, options);
  
  this.streams = {};
  
  if(typeof socket === 'string') {
    this._nextId = 0;
    this._socket = new WebSocket(socket);
  } else {
    // Use odd numbered ids for server originated streams
    this._nextId = 1;
    this._socket = socket;
  }
  
  this._socket.binaryType = 'arraybuffer';
  
  this._socket.addEventListener('open', function(){
    self.emit('open');
  });
  this._socket.addEventListener('error', function(error){
    var ids = Object.keys(self.streams);
    for (var i = 0, ii = ids.length; i < ii; i++) {
      self.streams[ids[i]]._onError(error);
    }
    self.emit('error', error);
  });
  this._socket.addEventListener('close', function(code, message){
    var ids = Object.keys(self.streams);
    for (var i = 0, ii = ids.length; i < ii; i++) {
      self.streams[ids[i]]._onClose();
    }
    self.emit('close', code, message);
  });
  this._socket.addEventListener('message', function(data, flags){
    util.setZeroTimeout(function(){
  
      // Message format
      // [type, payload, bonus ]
      //
      // Reserved
      // [ 0  , X , X ]
      // 
      //
      // New stream
      // [ 1  , Meta , new streamId ]
      // 
      //
      // Data
      // [ 2  , Data , streamId ]
      // 
      //
      // Pause
      // [ 3  , null , streamId ]
      // 
      //
      // Resume
      // [ 4  , null , streamId ]
      // 
      //
      // End
      // [ 5  , null , streamId ]
      // 
      //
      // Close
      // [ 6  , null , streamId ]
      // 
      
      data = data.data;
      
      try {
          data = util.unpack(data);
      } catch (ex) {
          return self.emit('error', new Error('Received unparsable message: ' + ex));
      }
      if (!(data instanceof Array))
          return self.emit('error', new Error('Received non-array message'));
      if (data.length != 3)
          return self.emit('error', new Error('Received message with wrong part count: ' + data.length));
      if ('number' != typeof data[0])
          return self.emit('error', new Error('Received message with non-number type: ' + data[0]));
      
      switch(data[0]) {
        case 0:
          // Reserved
          break;
        case 1:
          var meta = data[1];
          var streamId = data[2];
          var binaryStream = self._receiveStream(streamId);
          self.emit('stream', binaryStream, meta);
          break;
        case 2:
          var payload = data[1];
          var streamId = data[2];
          var binaryStream = self.streams[streamId];
          if(binaryStream) {
            binaryStream._onData(payload);
          } else {
            self.emit('error', new Error('Received `data` message for unknown stream: ' + streamId));
          }
          break;
        case 3:
          var streamId = data[2];
          var binaryStream = self.streams[streamId];
          if(binaryStream) {
            binaryStream._onPause();
          } else {
            self.emit('error', new Error('Received `pause` message for unknown stream: ' + streamId));
          }
          break;
        case 4:
          var streamId = data[2];
          var binaryStream = self.streams[streamId];
          if(binaryStream) {
            binaryStream._onResume();
          } else {
            self.emit('error', new Error('Received `resume` message for unknown stream: ' + streamId));
          }
          break;
        case 5:
          var streamId = data[2];
          var binaryStream = self.streams[streamId];
          if(binaryStream) {
            binaryStream._onEnd();
          } else {
            self.emit('error', new Error('Received `end` message for unknown stream: ' + streamId));
          }
          break;
        case 6:
          var streamId = data[2];
          var binaryStream = self.streams[streamId];
          if(binaryStream) {
            binaryStream._onClose();
          } else {
            self.emit('error', new Error('Received `close` message for unknown stream: ' + streamId));
          }
          break;
        default:
          self.emit('error', new Error('Unrecognized message type received: ' + data[0]));
      }
    });
  });
}

util.inherits(BinaryClient, EventEmitter);

BinaryClient.prototype.send = function(data, meta){
  var stream = this.createStream(meta);
  if(data instanceof Stream) {
    data.pipe(stream);
  } else if (util.isNode === true) {
    if(Buffer.isBuffer(data)) {
      (new BufferReadStream(data, {chunkSize: this._options.chunkSize})).pipe(stream);
    } else {
      stream.write(data);
    } 
  } else if (util.isNode !== true) {
    if(data.constructor == Blob || data.constructor == File) {
      (new BlobReadStream(data, {chunkSize: this._options.chunkSize})).pipe(stream);
    } else if (data.constructor == ArrayBuffer) {
      var blob;
      if(binaryFeatures.useArrayBufferView) {
        data = new Uint8Array(data);
      }
      if(binaryFeatures.useBlobBuilder) {
        var builder = new BlobBuilder();
        builder.append(data);
        blob = builder.getBlob()
      } else {
        blob = new Blob([data]);
      }
      (new BlobReadStream(blob, {chunkSize: this._options.chunkSize})).pipe(stream);
    } else if (typeof data === 'object' && 'BYTES_PER_ELEMENT' in data) {
      var blob;
      if(!binaryFeatures.useArrayBufferView) {
        // Warn
        data = data.buffer;
      }
      if(binaryFeatures.useBlobBuilder) {
        var builder = new BlobBuilder();
        builder.append(data);
        blob = builder.getBlob()
      } else {
        blob = new Blob([data]);
      }
      (new BlobReadStream(blob, {chunkSize: this._options.chunkSize})).pipe(stream);
    } else {
      stream.write(data);
    }
  }
  return stream;
};

BinaryClient.prototype._receiveStream = function(streamId){
  var self = this;
  var binaryStream = new BinaryStream(this._socket, streamId, false);
  binaryStream.on('close', function(){
    delete self.streams[streamId];
  });
  this.streams[streamId] = binaryStream;
  return binaryStream;
};

BinaryClient.prototype.createStream = function(meta){
  if(this._socket.readyState !== WebSocket.OPEN) {
    throw new Error('Client is not yet connected or has closed');
    return;
  }
  var self = this;
  var streamId = this._nextId;
  this._nextId += 2;
  var binaryStream = new BinaryStream(this._socket, streamId, true, meta);
  binaryStream.on('close', function(){
    delete self.streams[streamId];
  });
  this.streams[streamId] = binaryStream;
  return binaryStream;
};

BinaryClient.prototype.close = BinaryClient.prototype.destroy = function() {
  this._socket.close();
};

exports.BinaryClient = BinaryClient;

})(this);
	
</script>