def test_boyer_moore(self):
t = [1, 2, 3, 1, 2, 3, 1, 2, 3]
p = [1]
p_bm = BoyerMoore(p)
occurrences = boyer_moore(p, p_bm, t)
self.assertListEqual([0, 3, 6], occurrences,
"Test Case 1: " + str(p) + " in " + str(t))
t = [1, 2, 3, 1, 2, 3, 1, 2, 3]
p = [1, 2]
p_bm = BoyerMoore(p)
occurrences = boyer_moore(p, p_bm, t)
self.assertListEqual([0, 3, 6], occurrences,
"Test Case 2: " + str(p) + " in " + str(t))
t = [1, 2, 3, 1, 2, 3, 1, 2, 3]
p = [1, 2, 3]
p_bm = BoyerMoore(p)
occurrences = boyer_moore(p, p_bm, t)
self.assertListEqual([0, 3, 6], occurrences,
"Test Case 3: " + str(p) + " in " + str(t))
t = [1, 2, 3, 4, 5]
p = [6, 6, 6]
p_bm = BoyerMoore(p)
occurrences = boyer_moore(p, p_bm, t)
self.assertListEqual([], occurrences,
"test case 4: " + str(p) + " in " + str(t))
t = [1, 2, 3, 4, 5]
p = [6]
p_bm = BoyerMoore(p)
occurrences = boyer_moore(p, p_bm, t)
self.assertListEqual([], occurrences,
"test case 5: " + str(p) + " in " + str(t))
def test_boyer_moore(self):
t = [1, 2, 3, 1, 2, 3, 1, 2, 3]
p = [1]
p_bm = BoyerMoore(p)
occurrences = boyer_moore(p, p_bm, t)
self.assertListEqual([0, 3, 6], occurrences, "Test Case 1: " + str(p) + " in " + str(t))
t = [1, 2, 3, 1, 2, 3, 1, 2, 3]
p = [1, 2]
p_bm = BoyerMoore(p)
occurrences = boyer_moore(p, p_bm, t)
self.assertListEqual([0, 3, 6], occurrences, "Test Case 2: " + str(p) + " in " + str(t))
t = [1, 2, 3, 1, 2, 3, 1, 2, 3]
p = [1, 2, 3]
p_bm = BoyerMoore(p)
occurrences = boyer_moore(p, p_bm, t)
self.assertListEqual([0, 3, 6], occurrences, "Test Case 3: " + str(p) + " in " + str(t))
t = [1, 2, 3, 4, 5]
p = [6, 6, 6]
p_bm = BoyerMoore(p)
occurrences = boyer_moore(p, p_bm, t)
self.assertListEqual([], occurrences, "test case 4: " + str(p) + " in " + str(t))
t = [1, 2, 3, 4, 5]
p = [6]
p_bm = BoyerMoore(p)
occurrences = boyer_moore(p, p_bm, t)
self.assertListEqual([], occurrences, "test case 5: " + str(p) + " in " + str(t))
def parse(self, buffer, verify_index=True, update_index=True):
packet_list = []
original_buffer_length = len(buffer)
byte_consumed = 0
# header structure of possible packet
index_header = 0
index_header_iter = 0
index = 0
payload = None
operand = None
found = False
if len(buffer) < protoSBN1_constants.MIN_PACKET_LENGTH:
return packet_list, byte_consumed
p_bm = BoyerMoore(protoSBN1_constants.PROTOSBN1_HEADER_BYTES)
index_header_occurrences = boyer_moore(
protoSBN1_constants.PROTOSBN1_HEADER_BYTES, p_bm, buffer)
index_header_occurrences_num = len(index_header_occurrences)
while True:
# Find next header
if index_header_iter == index_header_occurrences_num:
# we do not have an header next
byte_consumed = original_buffer_length
break
index_header = index_header_occurrences[index_header_iter]
index_header_iter += 1
# We have a header now
if original_buffer_length - index_header < protoSBN1_constants.MIN_PACKET_LENGTH:
byte_consumed = index_header
break
# Check length
# expected packet length
# = len(op+payload) + 4 (SBN1) + 1 (index) + 1 (len) + 1 (checksum)
expected_packet_length = \
buffer[
index_header + protoSBN1_constants.LENGTH_OFFSET] \
+ protoSBN1_constants.MIN_PACKET_LENGTH
# Packet has a valid header, check payload length
if original_buffer_length - index_header < expected_packet_length:
# The packet is not long enough, keep these bytes
byte_consumed = index_header
break
elif expected_packet_length == protoSBN1_constants.MIN_PACKET_LENGTH:
# Zero length packet, drop
byte_consumed = index_header + protoSBN1_constants.MIN_PACKET_LENGTH
continue
# Check checksum
# We are separating operand and payload
payload = [0] * (
buffer[index_header + protoSBN1_constants.LENGTH_OFFSET] - 1)
payload = buffer[index_header +
protoSBN1_constants.PAYLOAD_OFFSET:index_header +
protoSBN1_constants.PAYLOAD_OFFSET + len(payload)]
checksum = buffer[index_header +
protoSBN1_constants.CHECKSUM_OFFSET]
operand = ProtoSBN1Operand(
buffer[index_header + protoSBN1_constants.OPERAND_OFFSET])
checksum_correct = self.verify_checksum(operand, payload, checksum)
# If the checksum is not correct, consume the header and move on
if not checksum_correct:
byte_consumed = index_header + len(
protoSBN1_constants.PROTOSBN1_HEADER_BYTES)
continue
# Verify index
index = buffer[index_header + protoSBN1_constants.INDEX_OFFSET]
if verify_index:
index_correct = self.verify_rx_index(index)
if index_correct:
found = True
else:
byte_consumed = index_header + protoSBN1_constants.MIN_PACKET_LENGTH
elif update_index:
# Update index accordingly
self.__rx_index = (index + 1) % 256
found = True
# Found a valid packet
if found:
packet = ProtoSBN1Packet(index, operand, payload)
packet_list.append(packet)
found = False
byte_consumed = index_header + len(packet.generate_bytes())
return packet_list, byte_consumed
def parse(self, buffer, verify_index=True, update_index=True):
packet_list = []
original_buffer_length = len(buffer)
byte_consumed = 0
# header structure of possible packet
index_header = 0
index_header_iter = 0
index = 0
payload = None
operand = None
found = False
if len(buffer) < protoSBN1_constants.MIN_PACKET_LENGTH:
return packet_list, byte_consumed
p_bm = BoyerMoore(protoSBN1_constants.PROTOSBN1_HEADER_BYTES)
index_header_occurrences = boyer_moore(
protoSBN1_constants.PROTOSBN1_HEADER_BYTES, p_bm,
buffer)
index_header_occurrences_num = len(index_header_occurrences)
while True:
# Find next header
if index_header_iter == index_header_occurrences_num:
# we do not have an header next
byte_consumed = original_buffer_length
break
index_header = index_header_occurrences[index_header_iter]
index_header_iter += 1
# We have a header now
if original_buffer_length - index_header < protoSBN1_constants.MIN_PACKET_LENGTH:
byte_consumed = index_header
break
# Check length
# expected packet length
# = len(op+payload) + 4 (SBN1) + 1 (index) + 1 (len) + 1 (checksum)
expected_packet_length = \
buffer[
index_header + protoSBN1_constants.LENGTH_OFFSET] \
+ protoSBN1_constants.MIN_PACKET_LENGTH
# Packet has a valid header, check payload length
if original_buffer_length - index_header < expected_packet_length:
# The packet is not long enough, keep these bytes
byte_consumed = index_header
break
elif expected_packet_length == protoSBN1_constants.MIN_PACKET_LENGTH:
# Zero length packet, drop
byte_consumed = index_header + protoSBN1_constants.MIN_PACKET_LENGTH
continue
# Check checksum
# We are separating operand and payload
payload = [0] * (buffer[
index_header + protoSBN1_constants.LENGTH_OFFSET] - 1)
payload = buffer[
index_header + protoSBN1_constants.PAYLOAD_OFFSET:index_header + protoSBN1_constants.PAYLOAD_OFFSET + len(
payload)]
checksum = buffer[
index_header + protoSBN1_constants.CHECKSUM_OFFSET]
operand = ProtoSBN1Operand(buffer[
index_header + protoSBN1_constants.OPERAND_OFFSET])
checksum_correct = self.verify_checksum(operand, payload, checksum)
# If the checksum is not correct, consume the header and move on
if not checksum_correct:
byte_consumed = index_header + len(
protoSBN1_constants.PROTOSBN1_HEADER_BYTES)
continue
# Verify index
index = buffer[
index_header + protoSBN1_constants.INDEX_OFFSET]
if verify_index:
index_correct = self.verify_rx_index(index)
if index_correct:
found = True
else:
byte_consumed = index_header + protoSBN1_constants.MIN_PACKET_LENGTH
elif update_index:
# Update index accordingly
self.__rx_index = (index + 1) % 256
found = True
# Found a valid packet
if found:
packet = ProtoSBN1Packet(index, operand, payload)
packet_list.append(packet)
found = False
byte_consumed = index_header + len(packet.generate_bytes())
return packet_list, byte_consumed
