text: var util = require('util');
  
  var debug;
  var debugLevel = parseInt(process.env.NODE_DEBUG, 16);
  if (debugLevel & 0x4) {
    debug = function (x) { util.error('HTTP: ' + x); };
  } else {
    debug = function () { };
  }
  
  var net = require('net');
  var stream = require('stream');
  
  var FreeList = require('freelist').FreeList;
  var HTTPParser = process.binding('http_parser').HTTPParser;
  
  var parsers = new FreeList('parsers', 1000, function () {
    var parser = new HTTPParser('request');
  
    parser.onMessageBegin = function () {
      parser.incoming = new IncomingMessage(parser.socket);
      parser.field = null;
      parser.value = null;
    };
  
    // Only servers will get URL events.
    parser.onURL = function (b, start, len) {
      var slice = b.toString('ascii', start, start+len);
      if (parser.incoming.url) {
        parser.incoming.url += slice;
      } else {
        // Almost always will branch here.
        parser.incoming.url = slice;
      }
    };
  
    parser.onHeaderField = function (b, start, len) {
      var slice = b.toString('ascii', start, start+len).toLowerCase();
      if (parser.value != undefined) {
        parser.incoming._addHeaderLine(parser.field, parser.value);
        parser.field = null;
        parser.value = null;
      }
      if (parser.field) {
        parser.field += slice;
      } else {
        parser.field = slice;
      }
    };
  
    parser.onHeaderValue = function (b, start, len) {
      var slice = b.toString('ascii', start, start+len);
      if (parser.value) {
        parser.value += slice;
      } else {
        parser.value = slice;
      }
    };
  
    parser.onHeadersComplete = function (info) {
      if (parser.field && (parser.value != undefined)) {
        parser.incoming._addHeaderLine(parser.field, parser.value);
        parser.field = null;
        parser.value = null;
      }
  
      parser.incoming.httpVersionMajor = info.versionMajor;
      parser.incoming.httpVersionMinor = info.versionMinor;
      parser.incoming.httpVersion = info.versionMajor
                                  + '.'
                                  + info.versionMinor ;
  
      if (info.method) {
        // server only
        parser.incoming.method = info.method;
      } else {
        // client only
        parser.incoming.statusCode = info.statusCode;  
      }
  
      parser.incoming.upgrade = info.upgrade;
  
      var isHeadResponse = false;
  
      if (!info.upgrade) {
        // For upgraded connections, we'll emit this after parser.execute
        // so that we can capture the first part of the new protocol
        isHeadResponse = parser.onIncoming(parser.incoming, info.shouldKeepAlive);
      }
  
      return isHeadResponse;
    };
  
    parser.onBody = function (b, start, len) {
      // TODO body encoding?
      var slice = b.slice(start, start+len);
      if (parser.incoming._decoder) {
        var string = parser.incoming._decoder.write(slice);
        if (string.length) parser.incoming.emit('data', string);
      } else {
        parser.incoming.emit('data', slice);
      }
    };
  
    parser.onMessageComplete = function () {
      this.incoming.complete = true;
      if (parser.field && (parser.value != undefined)) {
        parser.incoming._addHeaderLine(parser.field, parser.value);
      }
      if (!parser.incoming.upgrade) {
        // For upgraded connections, also emit this after parser.execute
        parser.incoming.emit("end");
      }
    };
  
    return parser;
  });
  exports.parsers = parsers;
  
  
  var CRLF = "\r\n";
  var STATUS_CODES = exports.STATUS_CODES = {
    100 : 'Continue',
    101 : 'Switching Protocols',
    102 : 'Processing',                 // RFC 2518, obsoleted by RFC 4918
    200 : 'OK',
    201 : 'Created',
    202 : 'Accepted',
    203 : 'Non-Authoritative Information',
    204 : 'No Content',
    205 : 'Reset Content',
    206 : 'Partial Content',
    207 : 'Multi-Status',               // RFC 4918
    300 : 'Multiple Choices',
    301 : 'Moved Permanently',
    302 : 'Moved Temporarily',
    303 : 'See Other',
    304 : 'Not Modified',
    305 : 'Use Proxy',
    307 : 'Temporary Redirect',
    400 : 'Bad Request',
    401 : 'Unauthorized',
    402 : 'Payment Required',
    403 : 'Forbidden',
    404 : 'Not Found',
    405 : 'Method Not Allowed',
    406 : 'Not Acceptable',
    407 : 'Proxy Authentication Required',
    408 : 'Request Time-out',
    409 : 'Conflict',
    410 : 'Gone',
    411 : 'Length Required',
    412 : 'Precondition Failed',
    413 : 'Request Entity Too Large',
    414 : 'Request-URI Too Large',
    415 : 'Unsupported Media Type',
    416 : 'Requested Range Not Satisfiable',
    417 : 'Expectation Failed',
    418 : 'I\'m a teapot',              // RFC 2324
    422 : 'Unprocessable Entity',       // RFC 4918
    423 : 'Locked',                     // RFC 4918
    424 : 'Failed Dependency',          // RFC 4918
    425 : 'Unordered Collection',       // RFC 4918
    426 : 'Upgrade Required',           // RFC 2817
    500 : 'Internal Server Error',
    501 : 'Not Implemented',
    502 : 'Bad Gateway',
    503 : 'Service Unavailable',
    504 : 'Gateway Time-out',
    505 : 'HTTP Version not supported',
    506 : 'Variant Also Negotiates',    // RFC 2295
    507 : 'Insufficient Storage',       // RFC 4918
    509 : 'Bandwidth Limit Exceeded',
    510 : 'Not Extended'                // RFC 2774
  };
  
  var connectionExpression = /Connection/i;
  var transferEncodingExpression = /Transfer-Encoding/i;
  var closeExpression = /close/i;
  var chunkExpression = /chunk/i;
  var contentLengthExpression = /Content-Length/i;
  var expectExpression = /Expect/i;
  var continueExpression = /100-continue/i;
  
  
  /* Abstract base class for ServerRequest and ClientResponse. */
  function IncomingMessage (socket) {
    stream.Stream.call(this);
  
    // TODO Remove one of these eventually.
    this.socket = socket;
    this.connection = socket;
  
    this.httpVersion = null;
    this.complete = false;
    this.headers = {};
    this.trailers = {};
  
    this.readable = true;
  
    // request (server) only
    this.url = "";
  
    this.method = null;
  
    // response (client) only
    this.statusCode = null;
    this.client = this.socket;
  }
  util.inherits(IncomingMessage, stream.Stream);
  exports.IncomingMessage = IncomingMessage;
  
  
  IncomingMessage.prototype.destroy = function (error) {
    this.socket.destroy(error);
  };
  
  
  IncomingMessage.prototype.setEncoding = function (encoding) {
    var StringDecoder = require("string_decoder").StringDecoder; // lazy load
    this._decoder = new StringDecoder(encoding);
  };
  
  IncomingMessage.prototype.pause = function () {
    this.socket.pause();
  };
  
  IncomingMessage.prototype.resume = function () {
    this.socket.resume();
  };
  
  // Add the given (field, value) pair to the message
  //
  // Per RFC2616, section 4.2 it is acceptable to join multiple instances of the
  // same header with a ', ' if the header in question supports specification of
  // multiple values this way. If not, we declare the first instance the winner
  // and drop the second. Extended header fields (those beginning with 'x-') are
  // always joined.
  IncomingMessage.prototype._addHeaderLine = function (field, value) {
    var dest;
    if (this.complete) {
        dest = this.trailers;
    } else {
        dest = this.headers;
    }
    switch (field) {
      // Array headers:
      case 'set-cookie':
        if (field in dest) {
          dest[field].push(value);
        } else {
          dest[field] = [value];
        }
        break;
  
      // Comma separate. Maybe make these arrays?
      case 'accept':
      case 'accept-charset':
      case 'accept-encoding':
      case 'accept-language':
      case 'connection':
      case 'cookie':
        if (field in dest) {
          dest[field] += ', ' + value;
        } else {
          dest[field] = value;
        }
        break;
  
  
      default:
        if (field.slice(0,2) == 'x-') {
          // except for x-
          if (field in dest) {
            dest[field] += ', ' + value;
          } else {
            dest[field] = value;
          }
        } else {
          // drop duplicates
          if (!(field in dest)) dest[field] = value;
        }
        break;
    }
  };
  
  function OutgoingMessage (socket) {
    stream.Stream.call(this);
  
    // TODO Remove one of these eventually.
    this.socket = socket;
    this.connection = socket;
  
    this.output = [];
    this.outputEncodings = [];
  
    this.writable = true;
  
    this._last = false;
    this.chunkedEncoding = false;
    this.shouldKeepAlive = true;
    this.useChunkedEncodingByDefault = true;
  
    this._hasBody = true;
    this._trailer = '';
  
    this.finished = false;
  }
  util.inherits(OutgoingMessage, stream.Stream);
  exports.OutgoingMessage = OutgoingMessage;
  
  
  OutgoingMessage.prototype.destroy = function (error) {
    this.socket.destroy(error);
  };
  
  
  // This abstract either writing directly to the socket or buffering it.
  OutgoingMessage.prototype._send = function (data, encoding) {
    // This is a shameful hack to get the headers and first body chunk onto
    // the same packet. Future versions of Node are going to take care of
    // this at a lower level and in a more general way.
    if (!this._headerSent) {
      if (typeof data === 'string') {
        data = this._header + data;
      } else {
        this.output.unshift(this._header);
        this.outputEncodings.unshift('ascii');
      }
      this._headerSent = true;
    }
    return this._writeRaw(data, encoding);
  };
  
  OutgoingMessage.prototype._writeRaw = function(data, encoding) {
    if (this.connection._outgoing[0] === this && this.connection.writable) {
      // There might be pending data in the this.output buffer.
      while (this.output.length) {
        if (!this.connection.writable) {
          this._buffer(data, encoding);
          return false;
        }
        var c = this.output.shift();
        var e = this.outputEncodings.shift();
        this.connection.write(c, e);
      }
  
      // Directly write to socket.
      return this.connection.write(data, encoding);
    } else {
      this._buffer(data, encoding);
      return false;
    }
  };
  
  OutgoingMessage.prototype._buffer = function (data, encoding) {
    if (data.length === 0) return;
  
    var length = this.output.length;
  
    if (length === 0 || typeof data != 'string') {
      this.output.push(data);
      encoding = encoding || "ascii";
      this.outputEncodings.push(encoding);
      return false;
    }
  
    var lastEncoding = this.outputEncodings[length-1];
    var lastData = this.output[length-1];
  
    if ((lastEncoding === encoding) ||
        (!encoding && data.constructor === lastData.constructor)) {
      this.output[length-1] = lastData + data;
      return false;
    }
  
    this.output.push(data);
    encoding = encoding || "ascii";
    this.outputEncodings.push(encoding);
  
    return false;
  };
  
  
  OutgoingMessage.prototype._storeHeader = function (firstLine, headers) {
    var sentConnectionHeader = false;
    var sentContentLengthHeader = false;
    var sentTransferEncodingHeader = false;
    var sentExpect = false;
  
    // firstLine in the case of request is: "GET /index.html HTTP/1.1\r\n"
    // in the case of response it is: "HTTP/1.1 200 OK\r\n"
    var messageHeader = firstLine;
    var field, value;
    var self = this;
  
    function store(field, value) {
      messageHeader += field + ": " + value + CRLF;
  
      if (connectionExpression.test(field)) {
        sentConnectionHeader = true;
        if (closeExpression.test(value)) {
          self._last = true;
        } else {
          self.shouldKeepAlive = true;
        }
  
      } else if (transferEncodingExpression.test(field)) {
        sentTransferEncodingHeader = true;
        if (chunkExpression.test(value)) self.chunkedEncoding = true;
  
      } else if (contentLengthExpression.test(field)) {
        sentContentLengthHeader = true;
  
      } else if (expectExpression.test(field)) {
        sentExpect = true;
  
      }
    }
  
    if (headers) {
      var keys = Object.keys(headers);
      var isArray = (Array.isArray(headers));
  
      for (var i = 0, l = keys.length; i < l; i++) {
        var key = keys[i];
        if (isArray) {
          field = headers[key][0];
          value = headers[key][1];
        } else {
          field = key;
          value = headers[key];
        }
  
        if (Array.isArray(value)) {
          for (var j = 0; j < value.length; j++) {
            store(field, value[j]);
          }
        } else {
          store(field, value);
        }
      }
    }
  
    // keep-alive logic
    if (sentConnectionHeader == false) {
      if (this.shouldKeepAlive &&
          (sentContentLengthHeader || this.useChunkedEncodingByDefault)) {
        messageHeader += "Connection: keep-alive\r\n";
      } else {
        this._last = true;
        messageHeader += "Connection: close\r\n";
      }
    }
  
    if (sentContentLengthHeader == false && sentTransferEncodingHeader == false) {
      if (this._hasBody) {
        if (this.useChunkedEncodingByDefault) {
          messageHeader += "Transfer-Encoding: chunked\r\n";
          this.chunkedEncoding = true;
        } else {
          this._last = true;
        }
      } else {
        // Make sure we don't end the 0\r\n\r\n at the end of the message.
        this.chunkedEncoding = false;
      }
    }
  
    this._header = messageHeader + CRLF;
    this._headerSent = false;
    // wait until the first body chunk, or close(), is sent to flush,
    // UNLESS we're sending Expect: 100-continue.
    if (sentExpect) {
        this._send("");
    }
  };
  
  OutgoingMessage.prototype.write = function (chunk, encoding) {
    if (!this._header) {
      throw new Error("You have to call writeHead() before write()");
    }
  
    if (!this._hasBody) {
      console.error("This type of response MUST NOT have a body. Ignoring write() calls.");
      return true;
    }
  
    if (typeof chunk !== "string"
        && !Buffer.isBuffer(chunk)
        && !Array.isArray(chunk)) {
      throw new TypeError("first argument must be a string, Array, or Buffer");
    }
  
    if (chunk.length === 0) return false;
  
    var len, ret;
    if (this.chunkedEncoding) {
      if (typeof(chunk) === 'string') {
        len = Buffer.byteLength(chunk, encoding);
        var chunk = len.toString(16) + CRLF + chunk + CRLF;
        debug('string chunk = ' + util.inspect(chunk));
        ret = this._send(chunk, encoding);
      } else {
        // buffer
        len = chunk.length;
        this._send(len.toString(16) + CRLF);
        this._send(chunk);
        ret = this._send(CRLF);
      }
    } else {
      ret = this._send(chunk, encoding);
    }
  
    debug('write ret = ' + ret);
    return ret;
  };
  
  
  OutgoingMessage.prototype.addTrailers = function (headers) {
    this._trailer = "";
    var keys = Object.keys(headers);
    var isArray = (Array.isArray(headers));
    for (var i = 0, l = keys.length; i < l; i++) {
      var key = keys[i];
      if (isArray) {
        field = headers[key][0];
        value = headers[key][1];
      } else {
        field = key;
        value = headers[key];
      }
  
      this._trailer += field + ": " + value + CRLF;
    }
  };
  
  
  OutgoingMessage.prototype.end = function (data, encoding) {
    var ret;
  
    var hot = this._headerSent === false
           && typeof(data) === "string"
           && data.length > 0
           && this.output.length === 0
           && this.connection.writable
           && this.connection._outgoing[0] === this
            ;
  
    if (hot) {
      // Hot path. They're doing
      //   res.writeHead();
      //   res.end(blah);
      // HACKY.
      if (this.chunkedEncoding) {
        var l = Buffer.byteLength(data, encoding).toString(16);
        ret = this.connection.write( this._header
                                   + l
                                   + CRLF
                                   + data
                                   + "\r\n0\r\n"
                                   + this._trailer
                                   + "\r\n"
                                   , encoding
                                   );
      } else {
        ret = this.connection.write(this._header + data, encoding);
      }
      this._headerSent = true;
  
    } else if (data) {
      // Normal body write.
      ret = this.write(data, encoding);
    }
  
    if (!hot) {
      if (this.chunkedEncoding) {
        ret = this._send('0\r\n' + this._trailer + '\r\n'); // Last chunk.
      } else {
        // Force a flush, HACK.
        ret = this._send('');
      }
    }
  
    this.finished = true;
  
    // There is the first message on the outgoing queue, and we've sent
    // everything to the socket.
    if (this.output.length === 0 && this.connection._outgoing[0] === this) {
      debug('outgoing message end. shifting because was flushed');
      this.connection._onOutgoingSent();
    }
  
    return ret;
  };
  
  
  function ServerResponse (req) {
    OutgoingMessage.call(this, req.socket);
  
    if (req.method === 'HEAD') this._hasBody = false;
  
    if (req.httpVersionMajor < 1 || req.httpVersionMinor < 1) {
      this.useChunkedEncodingByDefault = false;
      this.shouldKeepAlive = false;
    }
  }
  util.inherits(ServerResponse, OutgoingMessage);
  exports.ServerResponse = ServerResponse;
  
  ServerResponse.prototype.writeContinue = function () {
       this._writeRaw("HTTP/1.1 100 Continue" + CRLF + CRLF, 'ascii');
       this._sent100 = true;
  };
  
  ServerResponse.prototype.writeHead = function (statusCode) {
    var reasonPhrase, headers, headerIndex;
  
    if (typeof arguments[1] == 'string') {
      reasonPhrase = arguments[1];
      headerIndex = 2;
    } else {
      reasonPhrase = STATUS_CODES[statusCode] || "unknown";
      headerIndex = 1;
    }
  
    if (typeof arguments[headerIndex] == 'object') {
      headers = arguments[headerIndex];
    } else {
      headers = {};
    }
  
    var statusLine = "HTTP/1.1 " + statusCode.toString() + " "
                    + reasonPhrase + CRLF;
  
    if (   statusCode === 204 
        || statusCode === 304
        || (statusCode >= 100 && statusCode <= 199)
       ) {
      // RFC 2616, 10.2.5:
      // The 204 response MUST NOT include a message-body, and thus is always
      // terminated by the first empty line after the header fields.
      // RFC 2616, 10.3.5:
      // The 304 response MUST NOT contain a message-body, and thus is always
      // terminated by the first empty line after the header fields.
      // RFC 2616, 10.1 Informational 1xx:
      // This class of status code indicates a provisional response,
      // consisting only of the Status-Line and optional headers, and is
      // terminated by an empty line.
      this._hasBody = false;
    }
  
    // don't keep alive connections where the client expects 100 Continue
    // but we sent a final status; they may put extra bytes on the wire.
    if (this._expect_continue && ! this._sent100) {
        this._shouldKeepAlive = false;
    }
  
    this._storeHeader(statusLine, headers);
  };
  
  
  ServerResponse.prototype.writeHeader = function () {
    this.writeHead.apply(this, arguments);
  };
  
  function ClientRequest (socket, method, url, headers) {
    OutgoingMessage.call(this, socket);
  
    this.method = method = method.toUpperCase();
    this.shouldKeepAlive = false;
    if (method === "GET" || method === "HEAD") {
      this.useChunkedEncodingByDefault = false;
    } else {
      this.useChunkedEncodingByDefault = true;
    }
    this._last = true;
  
    this._storeHeader(method + " " + url + " HTTP/1.1\r\n", headers);
  }
  util.inherits(ClientRequest, OutgoingMessage);
  exports.ClientRequest = ClientRequest;
  
  function outgoingFlush (socket) {
    // This logic is probably a bit confusing. Let me explain a bit:
    //
    // In both HTTP servers and clients it is possible to queue up several
    // outgoing messages. This is easiest to imagine in the case of a client.
    // Take the following situation:
    //
    //    req1 = client.request('GET', '/');
    //    req2 = client.request('POST', '/');
    //
    // The question is what happens when the user does
    //
    //   req2.write("hello world\n");
    //
    // It's possible that the first request has not been completely flushed to
    // the socket yet. Thus the outgoing messages need to be prepared to queue
    // up data internally before sending it on further to the socket's queue.
    //
    // This function, outgoingFlush(), is called by both the Server
    // implementation and the Client implementation to attempt to flush any
    // pending messages out to the socket.
    var message = socket._outgoing[0];
  
    if (!message) return;
  
    var ret;
  
    while (message.output.length) {
      if (!socket.writable) return; // XXX Necessary?
  
      var data = message.output.shift();
      var encoding = message.outputEncodings.shift();
  
      ret = socket.write(data, encoding);
    }
  
    if (message.finished) {
      socket._onOutgoingSent();
    } else if (ret) {
      message.emit('drain');
    }
  }
  
  
  function httpSocketSetup (socket) {
    // An array of outgoing messages for the socket. In pipelined connections
    // we need to keep track of the order they were sent.
    socket._outgoing = [];
    socket.__destroyOnDrain = false;
  
    // NOTE: be sure not to use ondrain elsewhere in this file!
    socket.ondrain = function () {
      var message = socket._outgoing[0];
      if (message) message.emit('drain');
      if (socket.__destroyOnDrain) socket.destroy();
    };
  }
  
  
  
  function Server (requestListener) {
    if (!(this instanceof Server)) return new Server(requestListener);
    net.Server.call(this);
  
    if(requestListener){
      this.addListener("request", requestListener);
    }
  
    this.addListener("connection", connectionListener);
  }
  util.inherits(Server, net.Server);
  
  Server.prototype.setSecure = function (credentials) {
    this.secure = true;
    this.credentials = credentials;
  };
  
  exports.Server = Server;
  
  exports.createServer = function (requestListener) {
    return new Server(requestListener);
  };
  
  function connectionListener (socket) {
    var self = this;
  
    debug("new http connection");
  
    httpSocketSetup(socket);
  
    socket.setTimeout(2*60*1000); // 2 minute timeout
    socket.addListener('timeout', function () {
      socket.destroy();
    });
  
    var parser = parsers.alloc();
    parser.reinitialize('request');
    parser.socket = socket;
  
    if (self.secure) {
      socket.setSecure(self.credentials);
    }
  
    socket.addListener('error', function (e) {
      self.emit('clientError', e);
    });
  
    socket.ondata = function (d, start, end) {
      var ret = parser.execute(d, start, end - start);
      if (ret instanceof Error) {
        socket.destroy(ret);
      } else if (parser.incoming && parser.incoming.upgrade) {
        var bytesParsed = ret;
        socket.ondata = null;
        socket.onend = null;
  
        var req = parser.incoming;
  
        // This is start + byteParsed + 1 due to the error of getting \n
        // in the upgradeHead from the closing lines of the headers
        var upgradeHead = d.slice(start + bytesParsed + 1, end);
  
        if (self.listeners("upgrade").length) {
          self.emit('upgrade', req, req.socket, upgradeHead);
        } else {
          // Got upgrade header, but have no handler.
          socket.destroy();
        }
      }
    };
  
    socket.onend = function () {
      parser.finish();
  
      if (socket._outgoing.length) {
        socket._outgoing[socket._outgoing.length-1]._last = true;
        outgoingFlush(socket);
      } else {
        socket.end();
      }
    };
  
    socket.addListener('close', function () {
      // unref the parser for easy gc
      parsers.free(parser);
    });
  
    // At the end of each response message, after it has been flushed to the
    // socket.  Here we insert logic about what to do next.
    socket._onOutgoingSent = function (message) {
      var message = socket._outgoing.shift();
      if (message._last) {
        // No more messages to be pushed out.
  
        // HACK: need way to do this with socket interface
        if (socket._writeQueue.length) {
          socket.__destroyOnDrain = true; //socket.end();
        } else {
          socket.destroy();
        }
  
      } else if (socket._outgoing.length) {
        // Push out the next message.
        outgoingFlush(socket);
      }
    };
  
    // The following callback is issued after the headers have been read on a
    // new message. In this callback we setup the response object and pass it
    // to the user.
    parser.onIncoming = function (req, shouldKeepAlive) {
      var res = new ServerResponse(req);
      debug('server response shouldKeepAlive: ' + shouldKeepAlive);
      res.shouldKeepAlive = shouldKeepAlive;
      socket._outgoing.push(res);
  
      if ('expect' in req.headers
         && (req.httpVersionMajor == 1 && req.httpVersionMinor == 1)
         && continueExpression.test(req.headers['expect'])) {
          res._expect_continue = true;
          if (self.listeners("checkContinue").length) {
              self.emit("checkContinue", req, res);
          } else {
              res.writeContinue();
              self.emit('request', req, res);
          }
      } else {
          self.emit('request', req, res);
      }
      return false; // Not a HEAD response. (Not even a response!)
    };
  }
  
  
  function Client ( ) {
    if (!(this instanceof Client)) return new Client();
    net.Stream.call(this);
    var self = this;
  
    httpSocketSetup(self);
  
    function onData(d, start, end) {
      if (!self.parser) {
        throw new Error("parser not initialized prior to Client.ondata call");
      }
      var ret = self.parser.execute(d, start, end - start);
      if (ret instanceof Error) {
        self.destroy(ret);
      } else if (self.parser.incoming && self.parser.incoming.upgrade) {
        var bytesParsed = ret;
        self.ondata = null;
        self.onend = null;
  
        var req = self.parser.incoming;
  
        var upgradeHead = d.slice(start + bytesParsed + 1, end);
  
        if (self.listeners('upgrade').length) {
          self.emit('upgrade', req, self, upgradeHead);
        } else {
          self.destroy();
        }
      }
    };
  
    self.addListener("connect", function () {
      debug('client connected');
  
      self.ondata = onData;
      self.onend = onEnd;
  
      if (this.https) {
        this.setSecure(this.credentials);
      } else {
        self._initParser();
        debug('requests: ' + util.inspect(self._outgoing));
        outgoingFlush(self);
      }
    });
  
    self.addListener("secure", function () {
      self._initParser();
      debug('requests: ' + util.inspect(self._outgoing));
      outgoingFlush(self);
    });
  
    function onEnd() {
      if (self.parser) self.parser.finish();
      debug("self got end closing. readyState = " + self.readyState);
      self.end();
    };
  
    self.addListener("close", function (e) {
      if (e) return;
  
      debug("HTTP CLIENT onClose. readyState = " + self.readyState);
  
      // finally done with the request
      self._outgoing.shift();
  
      // If there are more requests to handle, reconnect.
      if (self._outgoing.length) {
        self._reconnect();
      } else if (self.parser) {
        parsers.free(self.parser);
        self.parser = null;
      }
    });
  };
  util.inherits(Client, net.Stream);
  
  exports.Client = Client;
  
  exports.createClient = function (port, host, https, credentials) {
    var c = new Client();
    c.port = port;
    c.host = host;
    c.https = https;
    c.credentials = credentials;
    return c;
  };
  
  
  Client.prototype._initParser = function () {
    var self = this;
    if (!self.parser) self.parser = parsers.alloc();
    self.parser.reinitialize('response');
    self.parser.socket = self;
    self.parser.onIncoming = function (res) {
      debug("incoming response!");
  
      var req = self._outgoing[0];
  
      // Responses to HEAD requests are AWFUL. Ask Ryan.
      // A major oversight in HTTP. Hence this nastiness.
      var isHeadResponse = req.method == "HEAD";
      debug('isHeadResponse ' + isHeadResponse);
        
      if (res.statusCode == 100) {
        // restart the parser, as this is a continue message.
        req.emit("continue");
        return true;
      }
      
      if (req.shouldKeepAlive && res.headers.connection === 'close') {
        req.shouldKeepAlive = false;
      }
  
      res.addListener('end', function ( ) {
        debug("request complete disconnecting. readyState = " + self.readyState);
        // For the moment we reconnect for every request. FIXME!
        // All that should be required for keep-alive is to not reconnect,
        // but outgoingFlush instead.
        if (req.shouldKeepAlive) {
          outgoingFlush(self);
          self._outgoing.shift();
          outgoingFlush(self);
        } else {
          self.end();
        }
      });
  
      req.emit("response", res);
  
      return isHeadResponse;
    };
  };
  
  
  // This is called each time a request has been pushed completely to the
  // socket. The message that was sent is still sitting at client._outgoing[0]
  // it is our responsibility to shift it off.
  //
  // We have to be careful when it we shift it because once we do any writes
  // to other requests will be flushed directly to the socket.
  //
  // At the moment we're implement a client which connects and disconnects on
  // each request/response cycle so we cannot shift off the request from
  // client._outgoing until we're completely disconnected after the response
  // comes back.
  Client.prototype._onOutgoingSent = function (message) {
    // We've just finished a message. We don't end/shutdown the connection here
    // because HTTP servers typically cannot handle half-closed connections
    // (Node servers can).
    //
    // Instead, we just check if the connection is closed, and if so
    // reconnect if we have pending messages.
    if (this._outgoing.length && this.readyState == "closed") {
      debug("HTTP client request flush. reconnect.  readyState = " + this.readyState);
      this._reconnect();
    }
  };
  
  
  Client.prototype._reconnect = function () {
    if (this.readyState === "closed") {
      debug("HTTP CLIENT: reconnecting readyState = " + this.readyState);
      this.connect(this.port, this.host);
    }
  };
  
  Client.prototype.request = function (method, url, headers) {
    if (typeof(url) != "string") {
      // assume method was omitted, shift arguments
      headers = url;
      url = method;
      method = "GET";
    }
    var req = new ClientRequest(this, method, url, headers);
    this._outgoing.push(req);
    if (this.readyState === 'closed') this._reconnect();
    return req;
  };
  
  
  exports.cat = function (url, encoding_, headers_) {
    var encoding = 'utf8',
        headers = {},
        callback = null;
  
    // parse the arguments for the various options... very ugly
    if (typeof(arguments[1]) == 'string') {
      encoding = arguments[1];
      if (typeof(arguments[2]) == 'object') {
        headers = arguments[2];
        if (typeof(arguments[3]) == 'function') callback = arguments[3];
      } else {
        if (typeof(arguments[2]) == 'function') callback = arguments[2];
      }
    } else {
      // didn't specify encoding
      if (typeof(arguments[1]) == 'object') {
        headers = arguments[1];
        callback = arguments[2];
      } else {
        callback = arguments[1];
      }
    }
  
    var url = require("url").parse(url);
  
    var hasHost = false;
    if (Array.isArray(headers)) {
      for (var i = 0, l = headers.length; i < l; i++) {
        if (headers[i][0].toLowerCase() === 'host') {
          hasHost = true;
          break;
        }
      }
    } else if (typeof headers === "Object") {
      var keys = Object.keys(headers);
      for (var i = 0, l = keys.length; i < l; i++) {
        var key = keys[i];
        if (key.toLowerCase() == 'host') {
          hasHost = true;
          break;
        }
      }
    }
    if (!hasHost) headers["Host"] = url.hostname;
  
    var content = "";
  
    var client = exports.createClient(url.port || 80, url.hostname);
    var req = client.request((url.pathname || "/")+(url.search || "")+(url.hash || ""), headers);
  
    if (url.protocol=="https:") {
        client.https = true;
    }
  
    var callbackSent = false;
  
    req.addListener('response', function (res) {
      if (res.statusCode < 200 || res.statusCode >= 300) {
        if (callback && !callbackSent) {
          callback(res.statusCode);
          callbackSent = true;
        }
        client.end();
        return;
      }
      res.setEncoding(encoding);
      res.addListener('data', function (chunk) { content += chunk; });
      res.addListener('end', function () {
        if (callback && !callbackSent) {
          callback(null, content);
          callbackSent = true;
        }
      });
    });
  
    client.addListener("error", function (err) {
      if (callback && !callbackSent) {
        callback(err);
        callbackSent = true;
      }
    });
  
    client.addListener("close", function () {
      if (callback && !callbackSent) {
        callback(new Error('Connection closed unexpectedly'));
        callbackSent = true;
      }
    });
    req.end();
  };
  