def handle_PIECE(self, peer_protocol, msg_payload):
print 'received piece from peer %r' % (peer_protocol.transport.getPeer())
peer_connection = self.get_peer_connection(peer_protocol)
index = get_4_bytes_in_decimal(msg_payload[0:4])
begin = get_4_bytes_in_decimal(msg_payload[4:8])
block = msg_payload[8:]
if not self.is_piece_valid(block, index):
# request piece again
piece_length = self.get_piece_length(piece_index)
self.request_piece(peer_connection, index, 0, piece_length)
peer_connection.piece_requested = index
return
print 'received piece index=%d' % index
# update which piece was received in master control bitfield
self.set_piece_received(index)
# reset requested piece
peer_connection.piece_requested = None
self.write_to_file(index, begin, block)
# check if there are more pieces left over
if self.has_retrieved_all_pieces():
print 'retrieved all pieces'
peer_connection.finished()
else:
peer_connection = self.get_peer_connection(peer_protocol)
self.request_next_piece(peer_connection)
def parse_message_helper(messages, buffer):
# JEFF - harder to confuse with msg_len if in all caps / constant
# Could use reduce here to create the aggregator and then call out to
# a separate function. Fun!
_msg_length_size = 4
# check for message length
if len(buffer) < _msg_length_size:
return messages, buffer
msg_len = get_4_bytes_in_decimal(buffer[0:_msg_length_size])
# keep alive message
if msg_len == 0:
messages.append(Message(id=ID_KEEPALIVE))
buffer = buffer[4:]
return parse_message_helper(messages, buffer)
# check for incomplete message
if len(buffer[1:]) < msg_len:
return messages, buffer
# consume complete message
msg_body = buffer[_msg_length_size : _msg_length_size + msg_len]
id, payload = get_message_id_and_payload(msg_body)
message = Message(msg_len=msg_len, id=id, payload=payload)
messages.append(message)
# remove parsed message and continue with the rest of the buffer
buffer = buffer[_msg_length_size + msg_len:]
return parse_message_helper(messages, buffer)
def parse_message_helper(messages, buffer):
_msg_length_size = 4
# check for message length
if len(buffer) < _msg_length_size:
return messages, buffer
msg_len = get_4_bytes_in_decimal(buffer[0:_msg_length_size])
# keep alive message
if msg_len == 0:
messages.append(Message(id=ID_KEEPALIVE))
buffer = buffer[4:]
return parse_message_helper(messages, buffer)
# check for incomplete message
if len(buffer[1:]) < msg_len:
return messages, buffer
# consume complete message
msg_body = buffer[_msg_length_size : _msg_length_size + msg_len]
id, payload = get_message_id_and_payload(msg_body)
message = Message(msg_len=msg_len, id=id, payload=payload)
messages.append(message)
# remove parsed message and continue with the rest of the buffer
buffer = buffer[_msg_length_size + msg_len:]
return parse_message_helper(messages, buffer)
def handle_HAVE(self, peer_protocol, msg_payload):
piece_index = get_4_bytes_in_decimal(msg_payload)
peer_connection = self.get_peer_connection(peer_protocol)
peer_connection.bitfield[piece_index] = True
