def process_ack(self, ack, ack_bits):
if not len(self.pending_ack_queue.queue):
return
should_remove = []
for packet in self.pending_ack_queue.queue:
acked = False
if packet.sequence == ack:
acked = True
elif not sequence_more_recent(packet.sequence, ack,
self.max_sequence):
bit_index = ReliabilitySystem.bit_index_for_sequence(
packet.sequence, ack, self.max_sequence)
if bit_index <= 31:
acked = (ack_bits >> bit_index) & 1
if acked:
self.rtt += (packet._time - self.rtt
) * 0.1 # exponentially smoothed moving average
self.acked_queue.insert_sorted(packet, self.max_sequence)
self.acks.append(packet.sequence)
self.acked_packets += 1
should_remove.append(packet)
for pack in should_remove:
self.pending_ack_queue.queue.remove(pack)
def _generate_ack_bits(ack, received_queue, max_sequence):
ack_bits = 0
for packet in received_queue.queue:
if packet.sequence == ack or sequence_more_recent(packet.sequence, ack, max_sequence):
break
bit_index = ReliabilitySystem.bit_index_for_sequence(packet.sequence, ack, max_sequence)
if bit_index <= 31:
ack_bits |= 1 << bit_index
return ack_bits
def bit_index_for_sequence(sequence, ack, max_sequence):
assert(sequence != ack)
assert(not sequence_more_recent(sequence, ack, max_sequence))
if sequence > ack:
assert(ack < 33)
assert(max_sequence >= sequence)
return ack + (max_sequence - sequence)
else:
assert(ack >= 1)
assert(sequence <= ack - 1)
return ack - 1 - sequence
def packet_received(self, sequence, size):
self.recv_packets += 1
if self.received_queue.exists(sequence):
return
packet = PacketData()
packet.sequence = sequence
packet._time = 0
packet.size = size
self.received_queue.queue.append(packet)
if sequence_more_recent(sequence, self.remote_sequence, self.max_sequence):
self.remote_sequence = sequence
def bit_index_for_sequence(sequence, ack, max_sequence):
assert (sequence != ack)
assert (not sequence_more_recent(sequence, ack, max_sequence))
if sequence > ack:
assert (ack < 33)
assert (max_sequence >= sequence)
return ack + (max_sequence - sequence)
else:
assert (ack >= 1)
assert (sequence <= ack - 1)
return ack - 1 - sequence
def _generate_ack_bits(ack, received_queue, max_sequence):
ack_bits = 0
for packet in received_queue.queue:
if packet.sequence == ack or sequence_more_recent(
packet.sequence, ack, max_sequence):
break
bit_index = ReliabilitySystem.bit_index_for_sequence(
packet.sequence, ack, max_sequence)
if bit_index <= 31:
ack_bits |= 1 << bit_index
return ack_bits
def packet_received(self, sequence, size):
self.recv_packets += 1
if self.received_queue.exists(sequence):
return
packet = PacketData()
packet.sequence = sequence
packet._time = 0
packet.size = size
self.received_queue.queue.append(packet)
if sequence_more_recent(sequence, self.remote_sequence,
self.max_sequence):
self.remote_sequence = sequence
def update_queues(self):
epsilon = 0.001
to_remove = []
for packet in self.sent_queue.queue:
if packet._time <= self.rtt_max + epsilon:
break
to_remove.append(packet)
for packet in to_remove:
self.sent_queue.queue.remove(packet)
if len(self.received_queue.queue):
latest_sequence = self.received_queue.queue[-1].sequence
min_sequence = latest_sequence - 34 if latest_sequence >= 34 else self.max_sequence - (
34 - latest_sequence)
to_remove = []
for i, packet in enumerate(self.received_queue.queue, 1):
if sequence_more_recent(packet.sequence, min_sequence,
self.max_sequence):
break
to_remove.append(packet)
for packet in to_remove:
self.received_queue.queue.remove(packet)
to_remove = []
for packet in self.acked_queue.queue:
if packet._time <= self.rtt_max * 2 - epsilon:
to_remove.append(packet)
for packet in to_remove:
self.acked_queue.queue.remove(packet)
to_remove = []
for packet in self.pending_ack_queue.queue:
if packet._time <= self.rtt_max + epsilon:
to_remove.append(packet)
for packet in to_remove:
self.pending_ack_queue.queue.remove(packet)
self.lost_packets += 1
def update_queues(self):
epsilon = 0.001
to_remove = []
for packet in self.sent_queue.queue:
if packet._time <= self.rtt_max + epsilon:
break
to_remove.append(packet)
for packet in to_remove:
self.sent_queue.queue.remove(packet)
if len(self.received_queue.queue):
latest_sequence = self.received_queue.queue[-1].sequence
min_sequence = latest_sequence - 34 if latest_sequence >= 34 else self.max_sequence - (34 - latest_sequence)
to_remove = []
for i, packet in enumerate(self.received_queue.queue, 1):
if sequence_more_recent(packet.sequence, min_sequence, self.max_sequence):
break
to_remove.append(packet)
for packet in to_remove:
self.received_queue.queue.remove(packet)
to_remove = []
for packet in self.acked_queue.queue:
if packet._time <= self.rtt_max * 2 - epsilon:
to_remove.append(packet)
for packet in to_remove:
self.acked_queue.queue.remove(packet)
to_remove = []
for packet in self.pending_ack_queue.queue:
if packet._time <= self.rtt_max + epsilon:
to_remove.append(packet)
for packet in to_remove:
self.pending_ack_queue.queue.remove(packet)
self.lost_packets += 1
def process_ack(self, ack, ack_bits):
if not len(self.pending_ack_queue.queue):
return
should_remove = []
for packet in self.pending_ack_queue.queue:
acked = False
if packet.sequence == ack:
acked = True
elif not sequence_more_recent(packet.sequence, ack, self.max_sequence):
bit_index = ReliabilitySystem.bit_index_for_sequence(packet.sequence, ack, self.max_sequence)
if bit_index <= 31:
acked = (ack_bits >> bit_index) & 1
if acked:
self.rtt += (packet._time - self.rtt) * 0.1 # exponentially smoothed moving average
self.acked_queue.insert_sorted(packet, self.max_sequence)
self.acks.append(packet.sequence)
self.acked_packets += 1
should_remove.append(packet)
for pack in should_remove:
self.pending_ack_queue.queue.remove(pack)