Merge branch 'zlib-compression' into packets-1.8

Conflicts:
	lib/protocol.js

index.js

@@ -141,6 +141,8 @@ function createServer(options) {
         hash = crypto.createHash("sha1");
         hash.update(serverId);
         client.once([states.LOGIN, 0x01], onEncryptionKeyResponse);
+        client.once([states.LOGIN, 0x03], onCompressionRequest);
+        client.on(  [states.PLAY,  0x46], onCompressionRequest);
         client.write(0x01, {
           serverId: serverId,
           publicKey: client.publicKey,
@@ -193,6 +195,10 @@ function createServer(options) {
       }
     }
 
+    function onCompressionRequest(packet) {
+        client.compressionThreshold = packet.threshold;
+    }
+
     function loginClient() {
         var isException = !!server.onlineModeExceptions[client.username.toLowerCase()];
       if (onlineMode == false || isException) {

lib/client.js

@@ -4,6 +4,7 @@ var net = require('net')
   , protocol = require('./protocol')
   , dns = require('dns')
   , createPacketBuffer = protocol.createPacketBuffer
+  , compressPacketBuffer = protocol.compressPacketBuffer
   , parsePacket = protocol.parsePacket
   , states = protocol.states
   , debug = protocol.debug
@@ -30,6 +31,7 @@ function Client(isServer) {
   this.encryptionEnabled = false;
   this.cipher = null;
   this.decipher = null;
+  this.compressionThreshold = -1;
   this.packetsToParse = {};
   this.on('newListener', function(event, listener) {
     var direction = this.isServer ? 'toServer' : 'toClient';
@@ -153,18 +155,38 @@ Client.prototype.write = function(packetId, params) {
     packetId = packetId[1];
   }
 
+  // TODO: Which comes first, encryption or compression?
+
+  var finishWriting = function(buffer) {
+      debug("writing packetId " + packetId + " (0x" + packetId.toString(16) + ")");
+      debug(params);
+      var out = this.encryptionEnabled ? new Buffer(this.cipher.update(buffer), 'binary') : buffer;
+      this.socket.write(out);
+      return true;
+  }
+
   var buffer = createPacketBuffer(packetId, this.state, params, this.isServer);
-  debug("writing packetId " + packetId + " (0x" + packetId.toString(16) + ")");
-  debug(params);
-  var out = this.encryptionEnabled ? new Buffer(this.cipher.update(buffer), 'binary') : buffer;
-  this.socket.write(out);
-  return true;
+  if(this.compressionThreshold != -1 && buffer.length > this.compressionThreshold) {
+      compressPacketBuffer(buffer, finishWriting);
+  } else {
+      finishWriting(buffer);
+  }
+
 };
 
 Client.prototype.writeRaw = function(buffer, shouldEncrypt) {
     if (shouldEncrypt === null) {
         shouldEncrypt = true;
     }
-    var out = (shouldEncrypt && this.encryptionEnabled) ? new Buffer(this.cipher.update(buffer), 'binary') : buffer;
-    this.socket.write(out);
+
+    var finishWriting = function(buffer) {
+        var out = (shouldEncrypt && this.encryptionEnabled) ? new Buffer(this.cipher.update(buffer), 'binary') : buffer;
+        this.socket.write(out);
+    };
+
+    if(this.compressionThreshold != -1 && buffer.length > this.compressionThreshold) {
+        compressPacketBuffer(buffer, finishWriting);
+    } else {
+        finishWriting(buffer);
+    }
 };

lib/protocol.js

@@ -1,5 +1,6 @@
 var assert = require('assert');
 var util = require('util');
+var zlib = require('zlib');
 
 var STRING_MAX_LENGTH = 240;
 var SRV_STRING_MAX_LENGTH = 32767;
@@ -58,6 +59,9 @@ var packets = {
       success:      {id: 0x02, fields: [
         { name: "uuid", type: "string" },
         { name: "username", type: "string" }
+      ]},
+      compress: { id: 0x03, fields: [
+        { name: "threshold", type: "varint"}
       ]}
     },
     toServer: {
@@ -1408,6 +1412,19 @@ function createPacketBuffer(packetId, state, params, isServer) {
   return buffer;
 }
 
+function compressPacketBuffer(buffer, callback) {
+    var dataLength   = buffer.length;
+    var packetLength = dataLength + sizeOfVarInt(dataLength);
+    var data = zlib.deflateRaw(buffer, function(compressedBuffer) {
+        var size = sizeOfVarInt(packetLength) + sizeOfVarInt(packetLength) + compressedBuffer.length;
+        var packetBuffer = new Buffer(size);
+        var offset = writeVarInt(packetLength, packetBuffer, 0);
+        offset = writeVarInt(dataLength, packetBuffer, offset);
+        writeVarInt(compressedBuffer, packetBuffer, offset);
+        callback(packetBuffer);
+    });
+}
+
 function parsePacket(buffer, state, isServer, packetsToParse) {
   if (state == null) state = states.PLAY;
   var cursor = 0;
@@ -1484,6 +1501,7 @@ module.exports = {
   sessionVersion: 13,
   parsePacket: parsePacket,
   createPacketBuffer: createPacketBuffer,
+  compressPacketBuffer: compressPacketBuffer,
   STRING_MAX_LENGTH: STRING_MAX_LENGTH,
   packetIds: packetIds,
   packetNames: packetNames,