Add a varint-delimiting stream as well.

lib/wire/messagestream.js

@@ -1,7 +1,7 @@
 var util = require('util')
 var stream = require('stream')
 
-function MessageStream() {
+function DelimitedStream() {
   stream.Transform.call(this)
   this._length = 0
   this._lengthIndex = 0
@@ -9,9 +9,9 @@ function MessageStream() {
   this._buffer = new Buffer(0)
 }
 
-util.inherits(MessageStream, stream.Transform)
+util.inherits(DelimitedStream, stream.Transform)
 
-MessageStream.prototype._transform = function(chunk, encoding, done) {
+DelimitedStream.prototype._transform = function(chunk, encoding, done) {
   this._buffer = Buffer.concat([this._buffer, chunk])
 
   var lo = 0
@@ -49,4 +49,34 @@ MessageStream.prototype._transform = function(chunk, encoding, done) {
   done()
 }
 
-module.exports = MessageStream
+module.exports.DelimitedStream = DelimitedStream
+
+function DelimitingStream() {
+  stream.Transform.call(this)
+}
+
+util.inherits(DelimitingStream, stream.Transform)
+
+DelimitingStream.prototype._transform = function(chunk, encoding, done) {
+  var length = chunk.length
+  var lengthBytes = []
+  var more = true
+
+  while (more) {
+    if (length > 0x7f) {
+      lengthBytes.push((1 << 7) + (length & 0x7f))
+      length >>= 7
+    }
+    else {
+      lengthBytes.push(length)
+      more = false
+    }
+  }
+
+  this.push(new Buffer(lengthBytes))
+  this.push(chunk)
+
+  done()
+}
+
+module.exports.DelimitingStream = DelimitingStream