PcapDriver.__init__() - Code Metrics - Inspection of "Add logging" - half2me/libant - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Pull Request — master (#3)

unknown

created 2016-10-13 08:17 UTC

PcapDriver.init() A

↳ Parent: PcapDriver

Complexity

Conditions

Size

Total Lines

Duplication

Lines	0
Ratio	0 %

Importance

Changes	9
Bugs	1	Features	0

Metric	Value
cc	1
c	9
b	1
f	0
dl	0
loc	7
rs	9.4285

from abc import abstractmethod
from queue import Queue
from threading import Lock, Thread, Event

import math
from serial import Serial, SerialException, SerialTimeoutException

import usb
import time
from struct import *

from libAnt.constants import MESSAGE_TX_SYNC, MESSAGE_CHANNEL_BROADCAST_DATA
from libAnt.message import Message, SystemResetMessage


class DriverException(Exception):
    pass

class Logger:
    def __init__(self, logFile: str):
        self._logFile = logFile
        self._log = None

    def __enter__(self):
        self.open()
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        self.close()

    def open(self):
        def validate(logFile: str) -> str:
            if '.' in logFile:
                name, ext = logFile.split('.', 2)
                ext = '.' + ext
            else:
                name = logFile
                ext = ''
            num = 0
            exists = True
            while(exists):
                logFile = name + '-' + str(num) + ext
                try:
                    with open(logFile):
                            pass
                except IOError:
                    return logFile
                num += 1

        if self._log is not None:
            self.close()
        self._logFile = validate(self._logFile)
        self._log = open(self._logFile, 'wb')
        self.onOpen()

    def close(self):
        if self._log is not None:
            self.beforeClose()
            self._log.close()
            self.afterClose()

    def log(self, data: bytes):
        self._log.write(self.encodeData(data))

    def onOpen(self):
        pass

    def beforeClose(self):
        pass

    def afterClose(self):
        pass

    def encodeData(self, data):
        return data

class PcapLogger(Logger):
    def onOpen(self):
        # write pcap global header
        magic_number = b'\xD4\xC3\xB2\xA1'
        version_major = 2
        version_minor = 4
        thiszone = b'\x00\x00\x00\x00'
        sigfigs = b'\x00\x00\x00\x00'
        snaplen = b'\xFF\x00\x00\x00'
        network = b'\x01\x00\x00\x00'
        pcap_global_header = Struct('<4shh4s4s4s4s')
        self._log.write(
            pcap_global_header.pack(magic_number, version_major, version_minor, thiszone, sigfigs,
                                    snaplen, network))

    def encodeData(self, data):
        timestamp = time.time()
        frac, whole = math.modf(timestamp)

        ts_sec = int(whole).to_bytes(4, byteorder='little')
        ts_usec = int(frac * 1000 * 1000).to_bytes(4, byteorder='little')
        incl_len = len(data)
        orig_len = incl_len

        pcap_packet_header = Struct('<4s4sll').pack(ts_sec, ts_usec, incl_len, orig_len)
        return pcap_packet_header + data

class Driver:
    """
    The driver provides an interface to read and write raw data to and from an ANT+ capable hardware device
    """

    def __init__(self, logger: Logger = None):
        self._lock = Lock()
        self._logger = logger
        self._openTime = None

    def __enter__(self):
        self.open()
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        self.close()

    def isOpen(self) -> bool:
        with self._lock:
            return self._isOpen()

    def open(self) -> None:
        with self._lock:
            if not self._isOpen():
                self._openTime = time.time()
                if self._logger is not None:
                    self._logger.open()
                self._open()

    def close(self) -> None:
        with self._lock:
            if self._isOpen:
                self._close()
                if self._logger is not None:
                    self._logger.close()

    def reOpen(self) -> None:
        with self._lock:
            if self._isOpen():
                self._close()
            self._open()

    def read(self, timeout=None) -> Message:
        # Splits the string into a list of tokens every n characters
        def splitN(str1, n):
            return [str1[start:start + n] for start in range(0, len(str1), n)]

        if not self.isOpen():
            raise DriverException("Device is closed")

        with self._lock:
            while True:
                sync = self._read(1, timeout=timeout)[0]
                if sync is not MESSAGE_TX_SYNC:
                    continue
                length = self._read(1, timeout=timeout)[0]
                type = self._read(1, timeout=timeout)[0]
                data = self._read(length, timeout=timeout)
                chk = self._read(1, timeout=timeout)[0]
                msg = Message(type, data)

                if self._logger:
                    logMsg = bytearray([sync, length, type])
                    logMsg.extend(data)
                    logMsg.append(chk)

                    self._logger.log(bytes(logMsg))

                if msg.checksum() == chk:
                    return msg

    def write(self, msg: Message) -> None:
        if not self.isOpen():
            raise DriverException("Device is closed")

        with self._lock:
            self._write(msg.encode())

    @abstractmethod
    def _isOpen(self) -> bool:
        pass

    @abstractmethod
    def _open(self) -> None:
        pass

    @abstractmethod
    def _close(self) -> None:
        pass

    @abstractmethod
    def _read(self, count: int, timeout=None) -> bytes:
        pass

    @abstractmethod
    def _write(self, data: bytes) -> None:
        pass


class SerialDriver(Driver):
    """
    An implementation of a serial ANT+ device driver
    """

    def __init__(self, device: str, baudRate: int = 115200, logger: Logger = None):
        super().__init__(logger=logger)
        self._device = device
        self._baudRate = baudRate
        self._serial = None

    def __str__(self):
        if self.isOpen():
            return self._device + " @ " + str(self._baudRate)
        return None

    def _isOpen(self) -> bool:
        return self._serial is None

    def _open(self) -> None:
        try:
            self._serial = Serial(self._device, self._baudRate)
        except SerialException as e:
            raise DriverException(str(e))

        if not self._serial.isOpen():
            raise DriverException("Could not open specified device")

    def _close(self) -> None:
        self._serial.close()
        self._serial = None

    def _read(self, count: int, timeout=None) -> bytes:
        return self._serial.read(count, timeout=timeout)

    def _write(self, data: bytes) -> None:
        try:
            self._serial.write(data)
            self._serial.flush()
        except SerialTimeoutException as e:
            raise DriverException(str(e))


class USBDriver(Driver):
    """
    An implementation of a USB ANT+ device driver
    """

    def __init__(self, vid, pid, logger: Logger = None):
        super().__init__(logger=logger)
        self._idVendor = vid
        self._idProduct = pid
        self._dev = None
        self._epOut = None
        self._epIn = None
        self._interfaceNumber = None
        self._packetSize = 0x20
        self._queue = None
        self._loop = None
        self._driver_open = False

    def __str__(self):
        if self.isOpen():
            return str(self._dev)
        return "Closed"

    class USBLoop(Thread):
        def __init__(self, ep, packetSize: int, queue: Queue):
            super().__init__()
            self._stopper = Event()
            self._ep = ep
            self._packetSize = packetSize
            self._queue = queue

        def stop(self) -> None:
            self._stopper.set()

        def run(self) -> None:
            while not self._stopper.is_set():
                try:
                    data = self._ep.read(self._packetSize, timeout=1000)
                    for d in data:
                        self._queue.put(d)
                except usb.core.USBError as e:
                    if e.errno not in (60, 110) and e.backend_error_code != -116:  # Timout errors
                        self._stopper.set()
            # We Put in an invalid byte so threads will realize the device is stopped
            self._queue.put(None)

    def _isOpen(self) -> bool:
        return self._driver_open

    def _open(self) -> None:
        print('USB OPEN START')
        try:
            # find the first USB device that matches the filter
            self._dev = usb.core.find(idVendor=self._idVendor, idProduct=self._idProduct)

            if self._dev is None:
                raise DriverException("Could not open specified device")

            # Detach kernel driver
            try:
                if self._dev.is_kernel_driver_active(0):
                    try:
                        self._dev.detach_kernel_driver(0)
                    except usb.USBError as e:
                        raise DriverException("Could not detach kernel driver")
            except NotImplementedError:
                pass  # for non unix systems

            # set the active configuration. With no arguments, the first
            # configuration will be the active one
            self._dev.set_configuration()

            # get an endpoint instance
            cfg = self._dev.get_active_configuration()
            self._interfaceNumber = cfg[(0, 0)].bInterfaceNumber
            interface = usb.util.find_descriptor(cfg, bInterfaceNumber=self._interfaceNumber,
                                                 bAlternateSetting=usb.control.get_interface(self._dev,
                                                                                             self._interfaceNumber))
            usb.util.claim_interface(self._dev, self._interfaceNumber)

            self._epOut = usb.util.find_descriptor(interface, custom_match=lambda e: usb.util.endpoint_direction(
                e.bEndpointAddress) == usb.ENDPOINT_OUT)

            self._epIn = usb.util.find_descriptor(interface, custom_match=lambda e: usb.util.endpoint_direction(
                e.bEndpointAddress) == usb.ENDPOINT_IN)

            if self._epOut is None or self._epIn is None:
                raise DriverException("Could not initialize USB endpoint")

            self._queue = Queue()
            self._loop = self.USBLoop(self._epIn, self._packetSize, self._queue)
            self._loop.start()
            self._driver_open = True
            print('USB OPEN SUCCESS')
        except IOError as e:
            self._close()
            raise DriverException(str(e))

    def _close(self) -> None:
        print('USB CLOSE START')
        if self._loop is not None:
            if self._loop.is_alive():
                self._loop.stop()
                self._loop.join()
        self._loop = None
        try:
            self._dev.reset()
            usb.util.dispose_resources(self._dev)
        except:
            pass
        self._dev = self._epOut = self._epIn = None
        self._driver_open = False
        print('USB CLOSE END')

    def _read(self, count: int, timeout=None) -> bytes:
        data = bytearray()
        for i in range(0, count):
            b = self._queue.get(timeout=timeout)
            if b is None:
                self._close()
                raise DriverException("Device is closed!")
            data.append(b)
        return bytes(data)

    def _write(self, data: bytes) -> None:
        return self._epOut.write(data)


class DummyDriver(Driver):
    def __init__(self, logger: Logger = None):
        super().__init__(logger=logger)
        self._isopen = False
        self._data = Queue()
        msg1 = Message(MESSAGE_CHANNEL_BROADCAST_DATA, b'\x00\x01\x02\x03\x04\x05\x06\x07').encode()
        for b in msg1:
            self._data.put(b)
        msg2 = Message(MESSAGE_CHANNEL_BROADCAST_DATA, b'\x00\xF1\xF2\xF3\xF4\xF5\xF6\xF7').encode()
        for b in msg2:
            self._data.put(b)
        msg3 = Message(MESSAGE_CHANNEL_BROADCAST_DATA, b'\x00\xF9\xFA\xFB\xFC\xFD\xFE\xFF').encode()
        for b in msg3:
            self._data.put(b)

    def _isOpen(self) -> bool:
        return self._isopen

    def _close(self) -> None:
        self._isopen = False

    def _read(self, count: int, timeout=None) -> bytes:
        data = bytearray()
        for i in range(0, count):
            data.append(self._data.get(timeout=timeout))
        return bytes(data)

    def _open(self) -> None:
        self._isopen = True

    def _write(self, data: bytes) -> None:
        pass


class PcapDriver(Driver):
    def __init__(self, pcap, logger: Logger = None):
        super().__init__(logger=logger)
        self._isopen = False
        self._pcap = pcap
        self._buffer = Queue()

        self._loop = None

    class PcapLoop(Thread):
        def __init__(self, pcap, buffer: Queue):
            super().__init__()
            self._stopper = Event()
            self._pcap = pcap
            self._buffer = buffer

        def stop(self) -> None:
            self._stopper.set()

        def run(self) -> None:
            self._pcapfile = open(self._pcap, 'rb')
            # move file pointer to first packet header
            global_header_length = 24
            self._pcapfile.seek(global_header_length, 0)

            first_ts = 0
            start_time = time.time()
            while not self._stopper.is_set():
                try:
                    ts_sec, = unpack('i', self._pcapfile.read(4))
                except error:
                    break
                ts_usec = unpack('i', self._pcapfile.read(4))[0] / 1000000

                if first_ts is 0:
                    first_ts = ts_sec + ts_usec

                ts = ts_sec + ts_usec
                send_time = ts - first_ts
                elapsed_time = time.time() - start_time
                if send_time > (elapsed_time):
                    sleep_time = send_time - elapsed_time
                    time.sleep(sleep_time)

                packet_length = unpack('i', self._pcapfile.read(4))[0]
                self._pcapfile.seek(4, 1)
                for i in range(packet_length):
                    self._buffer.put(self._pcapfile.read(1))

            self._pcapfile.close()

    def _isOpen(self) -> bool:
        return self._isopen

    def _open(self) -> None:
        self._isopen = True
        self._loop = self.PcapLoop(self._pcap, self._buffer)
        self._loop.start()

    def _close(self) -> None:
        self._isopen = False
        if self._loop is not None:
            if self._loop.is_alive():
                self._loop.stop()
                self._loop.join()
        self._loop = None

    def _read(self, count: int, timeout=None) -> bytes:
        result = bytearray()

        while len(result) < count:
            result += self._buffer.get(block=True, timeout=timeout)

        return bytes(result)

    def _write(self, data: bytes) -> None:
        pass


1			from abc import abstractmethod
2			from queue import Queue
3			from threading import Lock, Thread, Event
4
5			import math
6			from serial import Serial, SerialException, SerialTimeoutException
7
8			import usb
9			import time
10			from struct import *
11
12			from libAnt.constants import MESSAGE_TX_SYNC, MESSAGE_CHANNEL_BROADCAST_DATA
13			from libAnt.message import Message, SystemResetMessage
14
15
16			class DriverException(Exception):
17			pass
18
19			class Logger:
20			def __init__(self, logFile: str):
21			self._logFile = logFile
22			self._log = None
23
24			def __enter__(self):
25			self.open()
26			return self
27
28			def __exit__(self, exc_type, exc_val, exc_tb):
29			self.close()
30
31			def open(self):
32			def validate(logFile: str) -> str:
33			if '.' in logFile:
34			name, ext = logFile.split('.', 2)
35			ext = '.' + ext
36			else:
37			name = logFile
38			ext = ''
39			num = 0
40			exists = True
41			while(exists):
42			logFile = name + '-' + str(num) + ext
43			try:
44			with open(logFile):
45			pass
46			except IOError:
47			return logFile
48			num += 1
49
50			if self._log is not None:
51			self.close()
52			self._logFile = validate(self._logFile)
53			self._log = open(self._logFile, 'wb')
54			self.onOpen()
55
56			def close(self):
57			if self._log is not None:
58			self.beforeClose()
59			self._log.close()
60			self.afterClose()
61
62			def log(self, data: bytes):
63			self._log.write(self.encodeData(data))
64
65			def onOpen(self):
66			pass
67
68			def beforeClose(self):
69			pass
70
71			def afterClose(self):
72			pass
73
74			def encodeData(self, data):
75			return data
76
77			class PcapLogger(Logger):
78			def onOpen(self):
79			# write pcap global header
80			magic_number = b'\xD4\xC3\xB2\xA1'
81			version_major = 2
82			version_minor = 4
83			thiszone = b'\x00\x00\x00\x00'
84			sigfigs = b'\x00\x00\x00\x00'
85			snaplen = b'\xFF\x00\x00\x00'
86			network = b'\x01\x00\x00\x00'
87			pcap_global_header = Struct('<4shh4s4s4s4s')
88			self._log.write(
89			pcap_global_header.pack(magic_number, version_major, version_minor, thiszone, sigfigs,
90			snaplen, network))
91
92			def encodeData(self, data):
93			timestamp = time.time()
94			frac, whole = math.modf(timestamp)
95
96			ts_sec = int(whole).to_bytes(4, byteorder='little')
97			ts_usec = int(frac * 1000 * 1000).to_bytes(4, byteorder='little')
98			incl_len = len(data)
99			orig_len = incl_len
100
101			pcap_packet_header = Struct('<4s4sll').pack(ts_sec, ts_usec, incl_len, orig_len)
102			return pcap_packet_header + data
103
104			class Driver:
105			"""
106			The driver provides an interface to read and write raw data to and from an ANT+ capable hardware device
107			"""
108
109			def __init__(self, logger: Logger = None):
110			self._lock = Lock()
111			self._logger = logger
112			self._openTime = None
113
114			def __enter__(self):
115			self.open()
116			return self
117
118			def __exit__(self, exc_type, exc_val, exc_tb):
119			self.close()
120
121			def isOpen(self) -> bool:
122			with self._lock:
123			return self._isOpen()
124
125			def open(self) -> None:
126			with self._lock:
127			if not self._isOpen():
128			self._openTime = time.time()
129			if self._logger is not None:
130			self._logger.open()
131			self._open()
132
133			def close(self) -> None:
134			with self._lock:
135			if self._isOpen:
136			self._close()
137			if self._logger is not None:
138			self._logger.close()
139
140			def reOpen(self) -> None:
141			with self._lock:
142			if self._isOpen():
143			self._close()
144			self._open()
145
146			def read(self, timeout=None) -> Message:
147			# Splits the string into a list of tokens every n characters
148			def splitN(str1, n):
149			return [str1[start:start + n] for start in range(0, len(str1), n)]
150
151			if not self.isOpen():
152			raise DriverException("Device is closed")
153
154			with self._lock:
155			while True:
156			sync = self._read(1, timeout=timeout)[0]
157			if sync is not MESSAGE_TX_SYNC:
158			continue
159			length = self._read(1, timeout=timeout)[0]
160			type = self._read(1, timeout=timeout)[0]
161			data = self._read(length, timeout=timeout)
162			chk = self._read(1, timeout=timeout)[0]
163			msg = Message(type, data)
164
165			if self._logger:
166			logMsg = bytearray([sync, length, type])
167			logMsg.extend(data)
168			logMsg.append(chk)
169
170			self._logger.log(bytes(logMsg))
171
172			if msg.checksum() == chk:
173			return msg
174
175			def write(self, msg: Message) -> None:
176			if not self.isOpen():
177			raise DriverException("Device is closed")
178
179			with self._lock:
180			self._write(msg.encode())
181
182			@abstractmethod
183			def _isOpen(self) -> bool:
184			pass
185
186			@abstractmethod
187			def _open(self) -> None:
188			pass
189
190			@abstractmethod
191			def _close(self) -> None:
192			pass
193
194			@abstractmethod
195			def _read(self, count: int, timeout=None) -> bytes:
196			pass
197
198			@abstractmethod
199			def _write(self, data: bytes) -> None:
200			pass
201
202
203			class SerialDriver(Driver):
204			"""
205			An implementation of a serial ANT+ device driver
206			"""
207
208			def __init__(self, device: str, baudRate: int = 115200, logger: Logger = None):
209			super().__init__(logger=logger)
210			self._device = device
211			self._baudRate = baudRate
212			self._serial = None
213
214			def __str__(self):
215			if self.isOpen():
216			return self._device + " @ " + str(self._baudRate)
217			return None
218
219			def _isOpen(self) -> bool:
220			return self._serial is None
221
222			def _open(self) -> None:
223			try:
224			self._serial = Serial(self._device, self._baudRate)
225			except SerialException as e:
226			raise DriverException(str(e))
227
228			if not self._serial.isOpen():
229			raise DriverException("Could not open specified device")
230
231			def _close(self) -> None:
232			self._serial.close()
233			self._serial = None
234
235			def _read(self, count: int, timeout=None) -> bytes:
236			return self._serial.read(count, timeout=timeout)
237
238			def _write(self, data: bytes) -> None:
239			try:
240			self._serial.write(data)
241			self._serial.flush()
242			except SerialTimeoutException as e:
243			raise DriverException(str(e))
244
245
246			class USBDriver(Driver):
247			"""
248			An implementation of a USB ANT+ device driver
249			"""
250
251			def __init__(self, vid, pid, logger: Logger = None):
252			super().__init__(logger=logger)
253			self._idVendor = vid
254			self._idProduct = pid
255			self._dev = None
256			self._epOut = None
257			self._epIn = None
258			self._interfaceNumber = None
259			self._packetSize = 0x20
260			self._queue = None
261			self._loop = None
262			self._driver_open = False
263
264			def __str__(self):
265			if self.isOpen():
266			return str(self._dev)
267			return "Closed"
268
269			class USBLoop(Thread):
270			def __init__(self, ep, packetSize: int, queue: Queue):
271			super().__init__()
272			self._stopper = Event()
273			self._ep = ep
274			self._packetSize = packetSize
275			self._queue = queue
276
277			def stop(self) -> None:
278			self._stopper.set()
279
280			def run(self) -> None:
281			while not self._stopper.is_set():
282			try:
283			data = self._ep.read(self._packetSize, timeout=1000)
284			for d in data:
285			self._queue.put(d)
286			except usb.core.USBError as e:
287			if e.errno not in (60, 110) and e.backend_error_code != -116: # Timout errors
288			self._stopper.set()
289			# We Put in an invalid byte so threads will realize the device is stopped
290			self._queue.put(None)
291
292			def _isOpen(self) -> bool:
293			return self._driver_open
294
295			def _open(self) -> None:
296			print('USB OPEN START')
297			try:
298			# find the first USB device that matches the filter
299			self._dev = usb.core.find(idVendor=self._idVendor, idProduct=self._idProduct)
300
301			if self._dev is None:
302			raise DriverException("Could not open specified device")
303
304			# Detach kernel driver
305			try:
306			if self._dev.is_kernel_driver_active(0):
307			try:
308			self._dev.detach_kernel_driver(0)
309			except usb.USBError as e:
310			raise DriverException("Could not detach kernel driver")
311			except NotImplementedError:
312			pass # for non unix systems
313
314			# set the active configuration. With no arguments, the first
315			# configuration will be the active one
316			self._dev.set_configuration()
317
318			# get an endpoint instance
319			cfg = self._dev.get_active_configuration()
320			self._interfaceNumber = cfg[(0, 0)].bInterfaceNumber
321			interface = usb.util.find_descriptor(cfg, bInterfaceNumber=self._interfaceNumber,
322			bAlternateSetting=usb.control.get_interface(self._dev,
323			self._interfaceNumber))
324			usb.util.claim_interface(self._dev, self._interfaceNumber)
325
326			self._epOut = usb.util.find_descriptor(interface, custom_match=lambda e: usb.util.endpoint_direction(
327			e.bEndpointAddress) == usb.ENDPOINT_OUT)
328
329			self._epIn = usb.util.find_descriptor(interface, custom_match=lambda e: usb.util.endpoint_direction(
330			e.bEndpointAddress) == usb.ENDPOINT_IN)
331
332			if self._epOut is None or self._epIn is None:
333			raise DriverException("Could not initialize USB endpoint")
334
335			self._queue = Queue()
336			self._loop = self.USBLoop(self._epIn, self._packetSize, self._queue)
337			self._loop.start()
338			self._driver_open = True
339			print('USB OPEN SUCCESS')
340			except IOError as e:
341			self._close()
342			raise DriverException(str(e))
343
344			def _close(self) -> None:
345			print('USB CLOSE START')
346			if self._loop is not None:
347			if self._loop.is_alive():
348			self._loop.stop()
349			self._loop.join()
350			self._loop = None
351			try:
352			self._dev.reset()
353			usb.util.dispose_resources(self._dev)
354			except:
355			pass
356			self._dev = self._epOut = self._epIn = None
357			self._driver_open = False
358			print('USB CLOSE END')
359
360			def _read(self, count: int, timeout=None) -> bytes:
361			data = bytearray()
362			for i in range(0, count):
363			b = self._queue.get(timeout=timeout)
364			if b is None:
365			self._close()
366			raise DriverException("Device is closed!")
367			data.append(b)
368			return bytes(data)
369
370			def _write(self, data: bytes) -> None:
371			return self._epOut.write(data)
372
373
374			class DummyDriver(Driver):
375			def __init__(self, logger: Logger = None):
376			super().__init__(logger=logger)
377			self._isopen = False
378			self._data = Queue()
379			msg1 = Message(MESSAGE_CHANNEL_BROADCAST_DATA, b'\x00\x01\x02\x03\x04\x05\x06\x07').encode()
380			for b in msg1:
381			self._data.put(b)
382			msg2 = Message(MESSAGE_CHANNEL_BROADCAST_DATA, b'\x00\xF1\xF2\xF3\xF4\xF5\xF6\xF7').encode()
383			for b in msg2:
384			self._data.put(b)
385			msg3 = Message(MESSAGE_CHANNEL_BROADCAST_DATA, b'\x00\xF9\xFA\xFB\xFC\xFD\xFE\xFF').encode()
386			for b in msg3:
387			self._data.put(b)
388
389			def _isOpen(self) -> bool:
390			return self._isopen
391
392			def _close(self) -> None:
393			self._isopen = False
394
395			def _read(self, count: int, timeout=None) -> bytes:
396			data = bytearray()
397			for i in range(0, count):
398			data.append(self._data.get(timeout=timeout))
399			return bytes(data)
400
401			def _open(self) -> None:
402			self._isopen = True
403
404			def _write(self, data: bytes) -> None:
405			pass
406
407
408			class PcapDriver(Driver):
409			def __init__(self, pcap, logger: Logger = None):
410			super().__init__(logger=logger)
411			self._isopen = False
412			self._pcap = pcap
413			self._buffer = Queue()
414
415			self._loop = None
416
417			class PcapLoop(Thread):
418			def __init__(self, pcap, buffer: Queue):
419			super().__init__()
420			self._stopper = Event()
421			self._pcap = pcap
422			self._buffer = buffer
423
424			def stop(self) -> None:
425			self._stopper.set()
426
427			def run(self) -> None:
428			self._pcapfile = open(self._pcap, 'rb')
429			# move file pointer to first packet header
430			global_header_length = 24
431			self._pcapfile.seek(global_header_length, 0)
432
433			first_ts = 0
434			start_time = time.time()
435			while not self._stopper.is_set():
436			try:
437			ts_sec, = unpack('i', self._pcapfile.read(4))
438			except error:
439			break
440			ts_usec = unpack('i', self._pcapfile.read(4))[0] / 1000000
441
442			if first_ts is 0:
443			first_ts = ts_sec + ts_usec
444
445			ts = ts_sec + ts_usec
446			send_time = ts - first_ts
447			elapsed_time = time.time() - start_time
448			if send_time > (elapsed_time):
449			sleep_time = send_time - elapsed_time
450			time.sleep(sleep_time)
451
452			packet_length = unpack('i', self._pcapfile.read(4))[0]
453			self._pcapfile.seek(4, 1)
454			for i in range(packet_length):
455			self._buffer.put(self._pcapfile.read(1))
456
457			self._pcapfile.close()
458
459			def _isOpen(self) -> bool:
460			return self._isopen
461
462			def _open(self) -> None:
463			self._isopen = True
464			self._loop = self.PcapLoop(self._pcap, self._buffer)
465			self._loop.start()
466
467			def _close(self) -> None:
468			self._isopen = False
469			if self._loop is not None:
470			if self._loop.is_alive():
471			self._loop.stop()
472			self._loop.join()
473			self._loop = None
474
475			def _read(self, count: int, timeout=None) -> bytes:
476			result = bytearray()
477
478			while len(result) < count:
479			result += self._buffer.get(block=True, timeout=timeout)
480
481			return bytes(result)
482
483			def _write(self, data: bytes) -> None:
484			pass
485

half2me / libant

GitHub Access Token became invalid

Pull Request — master (#3)

PcapDriver.__init__() A

Complexity

Size

Duplication

Importance

Duplication Side-by-Side

Filter issues like

PcapDriver.init() A