def testEscapingSourceCanBecomeReadyAfterCallToNext(self):
mock = MockSource(deque([0x42, 0x43]))
escapingSource = EscapingSource(mock)
escapingSource.schedule()
escapingSource.next()
self.assertTrue(escapingSource.isReady())
self.assertTrue(escapingSource.read() == 0x43)
def testFrameReceiverIgnoresFrameWithBadCrc(self):
medium = deque()
medium += [EscapingSource.FLAG()]
crc = 0xFFFF
medium += [0x00]
crc = crc_ccitt_update(crc, 0x00)
medium += [0x42]
crc = crc_ccitt_update(crc, 0x42)
crc ^= 0x01
medium += [crc >> 8]
medium += [crc & 0xFF]
medium += [EscapingSource.FLAG()]
source = EscapingSource(MockSource(medium))
frameHandler = FrameHandler()
frameReceiver = FrameReceiver(source)
frameReceiver.setFrameHandler(frameHandler)
source.schedule()
while (source.isReady()):
frameReceiver.schedule()
source.schedule()
self.assertFalse(frameHandler.hasFrame())
def testFrameReceiverReceivesFrame(self):
medium = deque()
medium += [EscapingSource.FLAG()]
crc = 0xFFFF
medium += [0x00]
crc = crc_ccitt_update(crc, 0x00)
medium += [0x42]
crc = crc_ccitt_update(crc, 0x42)
medium += [crc >> 8]
medium += [crc & 0xFF]
medium += [EscapingSource.FLAG()]
source = EscapingSource(MockSource(medium))
frameHandler = FrameHandler()
frameReceiver = FrameReceiver(source)
frameReceiver.setFrameHandler(frameHandler)
source.schedule()
while (source.isReady()):
frameReceiver.schedule()
source.schedule()
self.assertEqual(0x00, frameHandler.header)
self.assertEqual([0x42], frameHandler.payload)
def testFrameReceiverReceivesMultipleFrames(self):
medium = deque()
count = 7
for i in range(0, count):
medium += [EscapingSource.FLAG()]
crc = 0xFFFF
medium += [0x00 + i]
crc = crc_ccitt_update(crc, 0x00 + i)
medium += [i]
crc = crc_ccitt_update(crc, i)
medium += [crc >> 8]
medium += [crc & 0xFF]
medium += [EscapingSource.FLAG()]
source = EscapingSource(MockSource(medium))
frameHandler = FrameHandler()
frameReceiver = FrameReceiver(source)
frameReceiver.setFrameHandler(frameHandler)
source.schedule()
while (source.isReady()):
frameReceiver.schedule()
source.schedule()
self.assertEqual(count, frameHandler.count)
def testEscapingSourceReceivesRegularOctetCorrectlyAfterReceivingFlag(
self):
mock = MockSource(deque([EscapingSource.FLAG(), 0x42]))
escapingSource = EscapingSource(mock)
escapingSource.schedule()
self.assertTrue(escapingSource.isFlag())
escapingSource.next()
escapingSource.schedule()
self.assertFalse(escapingSource.isFlag())
self.assertTrue(0x42 == escapingSource.read())
def testEscapingSourceCanBecomeReadyAfterCallToNextWithEscapeSequence(
self):
mock = MockSource(
deque(
[0x42,
EscapingSource.ESCAPE(), 0x43 ^ EscapingSource.MASK()]))
escapingSource = EscapingSource(mock)
escapingSource.schedule()
escapingSource.next()
self.assertTrue(escapingSource.isReady())
self.assertTrue(escapingSource.read() == 0x43)
def testFrameReceiverIgnoresEmptyFrames(self):
medium = deque()
medium += [EscapingSource.FLAG()]
medium += [EscapingSource.FLAG()]
source = EscapingSource(MockSource(medium))
frameHandler = FrameHandler()
frameReceiver = FrameReceiver(source)
frameReceiver.setFrameHandler(frameHandler)
source.schedule()
while (source.isReady()):
frameReceiver.schedule()
source.schedule()
self.assertFalse(frameHandler.hasFrame())
def testEscapingSourceReceivesEscapedOctetCorrectly(self):
mock = MockSource(
deque([
EscapingSource.ESCAPE(),
EscapingSource.FLAG() ^ EscapingSource.MASK(),
EscapingSource.ESCAPE(),
EscapingSource.ESCAPE() ^ EscapingSource.MASK()
]))
escapingSource = EscapingSource(mock)
escapingSource.schedule()
escapingSource.schedule()
self.assertFalse(escapingSource.isFlag())
self.assertTrue(EscapingSource.FLAG() == escapingSource.read())
escapingSource.next()
escapingSource.schedule()
escapingSource.schedule()
self.assertFalse(escapingSource.isFlag())
self.assertTrue(EscapingSource.ESCAPE() == escapingSource.read())
def testFrameReceiverRecognizesAckFrames(self):
medium = deque()
medium += [EscapingSource.FLAG()]
crc = 0xFFFF
medium += [FrameReceiver.ACK() + 0x24]
crc = crc_ccitt_update(crc, FrameReceiver.ACK() + 0x24)
medium += [crc >> 8]
medium += [crc & 0xFF]
medium += [EscapingSource.FLAG()]
source = EscapingSource(MockSource(medium))
frameHandler = FrameHandler()
frameReceiver = FrameReceiver(source)
frameReceiver.setFrameHandler(frameHandler)
source.schedule()
while (source.isReady()):
frameReceiver.schedule()
source.schedule()
self.assertEqual(FrameReceiver.ACK() + 0x24, frameHandler.header)
self.assertEqual([], frameHandler.payload)
def testEscapingSourceReceivesFlagOctetCorrectly(self):
mock = MockSource(deque([EscapingSource.FLAG()]))
escapingSource = EscapingSource(mock)
escapingSource.schedule()
self.assertTrue(escapingSource.isReady())
self.assertTrue(escapingSource.isFlag())
def testEscapingSourceReceivesOctetCorrectly(self):
mock = MockSource(deque([0x42]))
escapingSource = EscapingSource(mock)
escapingSource.schedule()
self.assertFalse(escapingSource.isFlag())
self.assertTrue(0x42 == escapingSource.read())
def testEscapingSourceBecomesUnreadyAfterReceiving(self):
mock = MockSource(deque([0x42]))
escapingSource = EscapingSource(mock)
escapingSource.schedule()
escapingSource.next()
self.assertFalse(escapingSource.isReady())
def testEscapingSourceIsBornUnready(self):
mock = MockSource(deque([0x42]))
escapingSource = EscapingSource(mock)
self.assertFalse(escapingSource.isReady())