fixup! WIP compressed write

Author: dougwilson

lib/protocol/PacketWriter.js

@@ -12,7 +12,6 @@ var Buffer       = require('safe-buffer').Buffer;
 var BufferList   = require('./BufferList');
 var EventEmitter = require('events').EventEmitter;
 var Util         = require('util');
-var Zlib         = require('zlib');
 
 module.exports = PacketWriter;
 function PacketWriter() {
@@ -44,14 +43,10 @@ PacketWriter.prototype.finalize = function finalize(parser) {
 
     var packetNumber = parser.incrementPacketNumber();
     var packetOffset = this._offset;
+    var start        = packet * MAX_PACKET_LENGTH;
+    var end          = start + packetLength;
 
-    this.writeUnsignedNumber(3, packetLength);
-    this.writeUnsignedNumber(1, packetNumber);
-
-    var start = packet * MAX_PACKET_LENGTH;
-    var end   = start + packetLength;
-
-    this.writeBuffer(buffer.slice(start, end));
+    this.writeBuffer(this._toPacket(packetNumber, buffer.slice(start, end)));
 
     if (!parser._compressed) {
       this.emit('data', this._buffer.slice(packetOffset, this._offset));
@@ -70,21 +65,11 @@ PacketWriter.prototype.finalize = function finalize(parser) {
         ? length % MAX_PACKET_LENGTH
         : MAX_PACKET_LENGTH;
 
-      packetNumber = parser.incrementCompressedPacketNumber();
-
-      this._buffer = Buffer.allocUnsafe(packetLength + COMPRESSED_PACKET_HEADER_LENGTH);
-      this._offset = 0;
-
-      this.writeUnsignedNumber(3, packetLength);
-      this.writeUnsignedNumber(1, packetNumber);
-      this.writeUnsignedNumber(3, 0);
-
+      var num   = parser.incrementCompressedPacketNumber();
       var start = packet * MAX_PACKET_LENGTH;
       var end   = start + packetLength;
 
-      this.writeBuffer(buffer.slice(start, end));
-
-      this.emit('data', this._buffer);
+      this.emit('data', this._toCompressedPacket(num, buffer.slice(start, end)));
     }
   }
 };
@@ -272,3 +257,42 @@ PacketWriter.prototype._allocate = function _allocate(bytes) {
   this._buffer = Buffer.alloc(newSize);
   oldBuffer.copy(this._buffer);
 };
+
+PacketWriter.prototype._toCompressedPacket = function _toCompressedPacket(num, buf) {
+  var origBuffer = this._buffer;
+  var origOffset = this._offset;
+
+  this._buffer = Buffer.allocUnsafe(buf.length + COMPRESSED_PACKET_HEADER_LENGTH);
+  this._offset = 0;
+
+  this.writeUnsignedNumber(3, buf.length);
+  this.writeUnsignedNumber(1, num);
+  this.writeUnsignedNumber(3, 0);
+  this.writeBuffer(buf);
+
+  var packet = this._buffer;
+
+  this._buffer = origBuffer;
+  this._offset = origOffset;
+
+  return packet;
+};
+
+PacketWriter.prototype._toPacket = function _toPacket(num, buf) {
+  var origBuffer = this._buffer;
+  var origOffset = this._offset;
+
+  this._buffer = Buffer.allocUnsafe(buf.length + PACKET_HEADER_LENGTH);
+  this._offset = 0;
+
+  this.writeUnsignedNumber(3, buf.length);
+  this.writeUnsignedNumber(1, num);
+  this.writeBuffer(buf);
+
+  var packet = this._buffer;
+
+  this._buffer = origBuffer;
+  this._offset = origOffset;
+
+  return packet;
+};