comments and clarifications

lib/WebSocketServer.js

@@ -313,23 +313,26 @@ function handleHixieUpgrade(req, socket, upgradeHead, cb) {
     cb(client);
   }
 
-  if (upgradeHead && upgradeHead.length >= 8) {
-    var nonce = upgradeHead.slice(0, 8);
-    var rest = upgradeHead.length > 8 ? upgradeHead.slice(8) : null;
+  var nonceLength = 8;
+  if (upgradeHead && upgradeHead.length >= nonceLength) {
+    var nonce = upgradeHead.slice(0, nonceLength);
+    var rest = upgradeHead.length > nonceLength ? upgradeHead.slice(nonceLength) : null;
     completeHandshake.call(this, nonce, rest);
   }
   else {
-    var nonce = new Buffer(8);
+    // nonce not present in upgradeHead, so we must wait for enough data
+    // data to arrive before continuing
+    var nonce = new Buffer(nonceLength);
     upgradeHead.copy(nonce, 0);
     var received = upgradeHead.length;
     var rest = null;
     var self = this;
     var handler = function (data) {
-      var toRead = Math.min(data.length, 8 - received);
+      var toRead = Math.min(data.length, nonceLength - received);
       if (toRead === 0) return;
       data.copy(nonce, received, 0, toRead);
       received += toRead;
-      if (received == 8) {
+      if (received == nonceLength) {
         socket.removeListener('data', handler);
         if (toRead < data.length) rest = data.slice(toRead);
         completeHandshake.call(self, nonce, rest);