def updatePackets(self, packet: Packet) -> bool:
if (packet.get_degree() == 1 and
next(iter(packet.get_used_packets())) < self.number_of_chunks
and (next(iter(packet.get_used_packets())) != 0
or not self.use_headerchunk)):
# Directly add Packets that are degree == 1 (except for HeaderPacket)
self.decodedPackets.add(packet)
return self.is_decoded()
self.queue.append(packet)
self.solve()
def __init__(self, packet: Packet, last_chunk_len_format: str = "I"):
assert packet.get_used_packets().issubset({0}), "only first packet can be HeaderPacket"
if isinstance(packet.data, numpy.ndarray):
self.data: bytes = packet.data.tobytes()
else:
self.data: bytes = packet.data
self.last_chunk_len_format: str = last_chunk_len_format
self.last_chunk_length, self.file_name = self.decode_header_info()
def compareAndReduce(self, packet: Packet, other: Packet) -> typing.Union[bool, int]:
if self.file is None: # In case of PseudoDecode: DO NOT REALLY COMPUTE XOR
packet.remove_packets(other.get_used_packets())
else:
packet.xor_and_remove_packet(other)
degree = packet.get_degree()
if (degree not in self.degreeToPacket) or (not isinstance(self.degreeToPacket[degree], set)):
self.degreeToPacket[degree] = set()
self.degreeToPacket[degree].add(packet)
if self.is_decoded():
return True
self.queue.append(packet)
return degree
def reduceAll(self, packet: Packet) -> bool:
# lookup all packets for this to solve with ( when this packet has a subset of used Packets)
fin: bool = False
lookup: typing.List[int] = [
i for i in self.degreeToPacket.keys() if packet.get_degree() < i
]
for i in lookup:
if not isinstance(self.degreeToPacket[i], set):
self.degreeToPacket[i] = set()
for p in self.degreeToPacket[i].copy():
p_used = p.get_used_packets()
pack_used = packet.get_used_packets()
if len(pack_used) < len(p_used) and pack_used.issubset(p_used):
self.degreeToPacket[i].remove(p)
degree = self.compareAndReduce(p, packet)
if isinstance(degree, bool) and degree is True:
return degree
degree: int = packet.get_degree()
lookup: typing.List[int] = [
i for i in self.degreeToPacket.keys() if packet.get_degree() > i
]
for i in lookup:
if not isinstance(self.degreeToPacket[i], set):
self.degreeToPacket[i] = set()
for p in self.degreeToPacket[i].copy():
p_used = p.get_used_packets()
pack_used = packet.get_used_packets()
if len(pack_used) > len(p_used) and p_used.issubset(pack_used):
try:
self.degreeToPacket[degree].remove(packet)
degree = self.compareAndReduce(packet, p)
if isinstance(degree, bool) and degree is True:
return degree
except:
continue
# If we already reduced a Packet with the same used_packets, there is no need to do it again
return fin or self.is_decoded()
def compareAndReduce(self, packet: Packet,
other: Packet) -> typing.Union[bool, int]:
if self.file is None:
packet.remove_packets(other.get_used_packets())
else:
packet.xor_and_remove_packet(other)
degree = packet.get_degree()
if (degree not in self.degreeToPacket) or (not isinstance(
self.degreeToPacket[degree], set)):
self.degreeToPacket[degree] = set()
if degree == 1:
[x] = (packet.get_used_packets()
) # Unpacking -> Fastest way to extract Element from Set
if x > self.number_of_chunks: # we got a new AUX-Packet
raise RuntimeError("this should not have happened!")
else:
if x != 0 or not self.use_headerchunk:
self.decodedPackets.add(
packet) # Add Packet to decoded Packets
self.degreeToPacket[degree].add(packet)
if self.is_decoded():
return True
self.queue.append(packet)
return degree
def __handle_lt(packet: Packet):
return packet.get_used_packets()