diff --git a/src/client.py b/src/client.py
--- a/src/client.py
+++ b/src/client.py
@@ -1,88 +1,88 @@
-from hashtree import HashTree
-import collections
-import socket
-import sys
-import logging as log
-
-import config as conf
-from networkers import NetworkReader,NetworkWriter
-
-
-filename=sys.argv[1]
-
-
-class Connection:
-	def __init__(self):
-		self.socket=socket.socket(socket.AF_INET,socket.SOCK_STREAM)
-		self.socket.connect((conf.hosts[0], conf.port))
-		fr=self.socket.makefile(mode="rb")
-		fw=self.socket.makefile(mode="wb")
-
-		self.incoming=NetworkReader(fr)
-		self.outcoming=NetworkWriter(fw)
-
-	def __enter__(self):
-		return self.incoming,self.outcoming
-
-	def __exit__(self, exc_type, exc_val, exc_tb):
-		self.socket.close()
-
-
-def negotiate():
-	localTree=HashTree.fromFile(open(filename,mode="rb"))
-	blocksToTransfer=[]
-	nodeStack=collections.deque([0]) # root
-
-	# initialize session
-	with Connection() as (incoming,outcoming):
-		jsonData={"command":"init", "blockSize":localTree.BLOCK_SIZE, "blockCount":localTree.leafCount, "version":conf.version}
-		outcoming.writeMsg(jsonData)
-
-	# determine which blocks to send
-	while len(nodeStack)>0:
-		with Connection() as (incoming,outcoming):
-			i=nodeStack.pop()
-			outcoming.writeMsg({"command":"req", "index":i})
-
-			jsonData,binData=incoming.readMsg()
-			assert jsonData["index"]==i
-			assert jsonData["dataType"]=="hash"
-
-			if localTree.store[i]!=binData:
-				if 2*i+3<len(localTree.store): # inner node
-					nodeStack.append(2*i+2)
-					nodeStack.append(2*i+1)
-				else: blocksToTransfer.append(i-localTree.leafStart) # leaf
-
-	return blocksToTransfer
-
-
-def sendData(blocksToTransfer):
-	log.info(blocksToTransfer)
-	dataFile=open(filename,mode="rb")
-	i1=-1
-
-	for i2 in blocksToTransfer:
-		with Connection() as (incoming,outcoming):
-			jsonData={"command":"send", "index":i2, "dataType":"data"}
-			if i1+1!=i2:
-				dataFile.seek(i2*HashTree.BLOCK_SIZE)
-			binData=dataFile.read(HashTree.BLOCK_SIZE)
-
-			log.info("block #{0}: {1}...{2}".format(i2,binData[:5],binData[-5:]))
-
-			outcoming.writeMsg(jsonData,binData)
-			i1=i2
-
-	with Connection() as (incoming,outcoming):
-		outcoming.writeMsg({"command":"end"})
-
-	log.info("closing session...")
-	dataFile.close()
-
-
-if __name__=="__main__":
-	blocksToTransfer=negotiate()
-	sendData(blocksToTransfer)
-
-	sys.exit(0)
+from hashtree import HashTree
+import collections
+import socket
+import sys
+import logging as log
+
+import config as conf
+from networkers import NetworkReader,NetworkWriter
+
+
+filename=sys.argv[1]
+
+
+class Connection:
+	def __init__(self):
+		self.socket=socket.socket(socket.AF_INET,socket.SOCK_STREAM)
+		self.socket.connect((conf.hosts[0], conf.port))
+		fr=self.socket.makefile(mode="rb")
+		fw=self.socket.makefile(mode="wb")
+
+		self.incoming=NetworkReader(fr)
+		self.outcoming=NetworkWriter(fw)
+
+	def __enter__(self):
+		return self.incoming,self.outcoming
+
+	def __exit__(self, exc_type, exc_val, exc_tb):
+		self.socket.close()
+
+
+def negotiate():
+	localTree=HashTree.fromFile(open(filename,mode="rb"))
+	blocksToTransfer=[]
+	nodeStack=collections.deque([0]) # root
+
+	# initialize session
+	with Connection() as (incoming,outcoming):
+		jsonData={"command":"init", "blockSize":localTree.BLOCK_SIZE, "blockCount":localTree.leafCount, "version":conf.version}
+		outcoming.writeMsg(jsonData)
+
+	# determine which blocks to send
+	while len(nodeStack)>0:
+		with Connection() as (incoming,outcoming):
+			i=nodeStack.pop()
+			outcoming.writeMsg({"command":"req", "index":i})
+
+			jsonData,binData=incoming.readMsg()
+			assert jsonData["index"]==i
+			assert jsonData["dataType"]=="hash"
+
+			if localTree.store[i]!=binData:
+				if 2*i+3<len(localTree.store): # inner node
+					nodeStack.append(2*i+2)
+					nodeStack.append(2*i+1)
+				else: blocksToTransfer.append(i-localTree.leafStart) # leaf
+
+	return blocksToTransfer
+
+
+def sendData(blocksToTransfer):
+	log.info(blocksToTransfer)
+	dataFile=open(filename,mode="rb")
+	i1=-1
+
+	for i2 in blocksToTransfer:
+		with Connection() as (incoming,outcoming):
+			jsonData={"command":"send", "index":i2, "dataType":"data"}
+			if i1+1!=i2:
+				dataFile.seek(i2*HashTree.BLOCK_SIZE)
+			binData=dataFile.read(HashTree.BLOCK_SIZE)
+
+			log.info("block #{0}: {1}...{2}".format(i2,binData[:5],binData[-5:]))
+
+			outcoming.writeMsg(jsonData,binData)
+			i1=i2
+
+	with Connection() as (incoming,outcoming):
+		outcoming.writeMsg({"command":"end"})
+
+	log.info("closing session...")
+	dataFile.close()
+
+
+if __name__=="__main__":
+	blocksToTransfer=negotiate()
+	sendData(blocksToTransfer)
+
+	sys.exit(0)