Python select.POLLNVAL Examples

def _ensure_communication(self, timeout=None):

        "Ensure that sending and receiving are possible."

        while 1:
            self._ensure_pipes()
            fileno = self.write_pipe.fileno()
            fds = self.poller.poll(timeout)
            for fd, status in fds:
                if fd != fileno:
                    continue
                if status & (select.POLLHUP | select.POLLNVAL | select.POLLERR):

                    # Broken connection: discard it and start all over again.

                    self._reset_pipes()
                    break
            else:
                return 

def readwrite(obj, flags):
    try:
        if flags & select.POLLIN:
            obj.handle_read_event()
        if flags & select.POLLOUT:
            obj.handle_write_event()
        if flags & select.POLLPRI:
            obj.handle_expt_event()
        if flags & (select.POLLHUP | select.POLLERR | select.POLLNVAL):
            obj.handle_close()
    except OSError as e:
        if e.args[0] not in _DISCONNECTED:
            obj.handle_error()
        else:
            obj.handle_close()
    except _reraised_exceptions:
        raise
    except:
        obj.handle_error() 

def _parse_events(self, events):
        """Parse ``events``.

        ``events`` is a list of events as returned by
        :meth:`select.poll.poll()`.

        Yield all parsed events.

        """
        for fd, event_mask in events:
            if self._has_event(event_mask, select.POLLNVAL):
                raise IOError('File descriptor not open: {0!r}'.format(fd))
            elif self._has_event(event_mask, select.POLLERR):
                raise IOError('Error while polling fd: {0!r}'.format(fd))

            if self._has_event(event_mask, select.POLLIN):
                yield fd, 'r'
            if self._has_event(event_mask, select.POLLOUT):
                yield fd, 'w'
            if self._has_event(event_mask, select.POLLHUP):
                yield fd, 'h' 

def run(self):
        #print(self.run, 'enter')
        while True:
            #print(self.run, 'cycle')
            pollret = dict(self.pollobj.poll()).get(self.fileno, 0)
            if pollret & POLLNVAL != 0:
                break
            if pollret & POLLIN == 0:
                continue
            try:
                clientsock, addr = self.clicm.serversock.accept()
            except Exception as why:
                if isinstance(why, socket.error):
                    if why.errno == ECONNABORTED:
                        continue
                    elif why.errno == EBADF:
                        break
                    else:
                        raise
                dump_exception('CLIConnectionManager: unhandled exception when accepting incoming connection')
                break
            #print(self.run, 'handle_accept')
            ED2.callFromThread(self.clicm.handle_accept, clientsock, addr)
        self.clicm = None
        #print(self.run, 'exit') 

def read(self, size=1):
        """Read size bytes from the serial port. If a timeout is set it may
           return less characters as requested. With no timeout it will block
           until the requested number of bytes is read."""
        if self.fd is None: raise portNotOpenError
        read = bytearray()
        poll = select.poll()
        poll.register(self.fd, select.POLLIN|select.POLLERR|select.POLLHUP|select.POLLNVAL)
        if size > 0:
            while len(read) < size:
                # print "\tread(): size",size, "have", len(read)    #debug
                # wait until device becomes ready to read (or something fails)
                for fd, event in poll.poll(self._timeout*1000):
                    if event & (select.POLLERR|select.POLLHUP|select.POLLNVAL):
                        raise SerialException('device reports error (poll)')
                    #  we don't care if it is select.POLLIN or timeout, that's
                    #  handled below
                buf = os.read(self.fd, size - len(read))
                read.extend(buf)
                if ((self._timeout is not None and self._timeout >= 0) or 
                    (self._interCharTimeout is not None and self._interCharTimeout > 0)) and not buf:
                    break   # early abort on timeout
        return bytes(read) 

def run(self):
        #print(self.run, 'enter')
        while True:
            #print(self.run, 'cycle')
            pollret = dict(self.pollobj.poll()).get(self.fileno, 0)
            if pollret & POLLNVAL != 0:
                break
            if pollret & POLLIN == 0:
                continue
            try:
                clientsock, addr = self.clicm.serversock.accept()
            except Exception as why:
                if isinstance(why, socket.error):
                    if why.errno == ECONNABORTED:
                        continue
                    elif why.errno == EBADF:
                        break
                    else:
                        raise
                dump_exception('CLIConnectionManager: unhandled exception when accepting incoming connection')
                break
            #print(self.run, 'handle_accept')
            ED2.callFromThread(self.clicm.handle_accept, clientsock, addr)
        self.clicm = None
        #print(self.run, 'exit') 

def read(self, size=1):
        """Read size bytes from the serial port. If a timeout is set it may
           return less characters as requested. With no timeout it will block
           until the requested number of bytes is read."""
        if self.fd is None: raise portNotOpenError
        read = bytearray()
        poll = select.poll()
        poll.register(self.fd, select.POLLIN|select.POLLERR|select.POLLHUP|select.POLLNVAL)
        if size > 0:
            while len(read) < size:
                # print "\tread(): size",size, "have", len(read)    #debug
                # wait until device becomes ready to read (or something fails)
                for fd, event in poll.poll(self._timeout*1000):
                    if event & (select.POLLERR|select.POLLHUP|select.POLLNVAL):
                        raise SerialException('device reports error (poll)')
                    #  we don't care if it is select.POLLIN or timeout, that's
                    #  handled below
                buf = os.read(self.fd, size - len(read))
                read.extend(buf)
                if ((self._timeout is not None and self._timeout >= 0) or 
                    (self._interCharTimeout is not None and self._interCharTimeout > 0)) and not buf:
                    break   # early abort on timeout
        return bytes(read) 

def read(self, size=1):
        """Read size bytes from the serial port. If a timeout is set it may
           return less characters as requested. With no timeout it will block
           until the requested number of bytes is read."""
        if self.fd is None: raise portNotOpenError
        read = bytearray()
        poll = select.poll()
        poll.register(self.fd, select.POLLIN|select.POLLERR|select.POLLHUP|select.POLLNVAL)
        if size > 0:
            while len(read) < size:
                # print "\tread(): size",size, "have", len(read)    #debug
                # wait until device becomes ready to read (or something fails)
                for fd, event in poll.poll(self._timeout*1000):
                    if event & (select.POLLERR|select.POLLHUP|select.POLLNVAL):
                        raise SerialException('device reports error (poll)')
                    #  we don't care if it is select.POLLIN or timeout, that's
                    #  handled below
                buf = os.read(self.fd, size - len(read))
                read.extend(buf)
                if ((self._timeout is not None and self._timeout >= 0) or 
                    (self._interCharTimeout is not None and self._interCharTimeout > 0)) and not buf:
                    break   # early abort on timeout
        return bytes(read) 

def readwrite(obj, flags):
    try:
        if flags & select.POLLIN:
            obj.handle_read_event()
        if flags & select.POLLOUT:
            obj.handle_write_event()
        if flags & select.POLLPRI:
            obj.handle_expt_event()
        if flags & (select.POLLHUP | select.POLLERR | select.POLLNVAL):
            obj.handle_close()
    except OSError as e:
        if e.args[0] not in _DISCONNECTED:
            obj.handle_error()
        else:
            obj.handle_close()
    except _reraised_exceptions:
        raise
    except:
        obj.handle_error() 

def readwrite(obj, flags):
    try:
        if flags & select.POLLIN:
            obj.handle_read_event()
        if flags & select.POLLOUT:
            obj.handle_write_event()
        if flags & select.POLLPRI:
            obj.handle_expt_event()
        if flags & (select.POLLHUP | select.POLLERR | select.POLLNVAL):
            obj.handle_close()
    except OSError as e:
        if e.args[0] not in _DISCONNECTED:
            obj.handle_error()
        else:
            obj.handle_close()
    except _reraised_exceptions:
        raise
    except:
        obj.handle_error() 

def poll(self, timeout = None):
            events = self._poll.poll(timeout)
            processed = []
            for fd, evt in events:
                mask = ""
                if evt & (select_module.POLLIN | select_module.POLLPRI):
                    mask += "r"
                if evt & select_module.POLLOUT:
                    mask += "w"
                if evt & select_module.POLLERR:
                    mask += "e"
                if evt & select_module.POLLHUP:
                    mask += "h"
                if evt & select_module.POLLNVAL:
                    mask += "n"
                processed.append((fd, mask))
            return processed 

def _poll(fds, timeout):
        if timeout is not None:
            timeout = int(timeout * 1000)  # timeout is in milliseconds
        fd_map = {}
        pollster = select.poll()
        for fd in fds:
            pollster.register(fd, select.POLLIN)
            if hasattr(fd, 'fileno'):
                fd_map[fd.fileno()] = fd
            else:
                fd_map[fd] = fd
        ls = []
        for fd, event in pollster.poll(timeout):
            if event & select.POLLNVAL:  # pragma: no cover
                raise ValueError('invalid file descriptor %i' % fd)
            ls.append(fd_map[fd])
        return ls 

def poll(self, timeout = None):
            events = self._poll.poll(timeout)
            processed = []
            for fd, evt in events:
                mask = ""
                if evt & (select_module.POLLIN | select_module.POLLPRI):
                    mask += "r"
                if evt & select_module.POLLOUT:
                    mask += "w"
                if evt & select_module.POLLERR:
                    mask += "e"
                if evt & select_module.POLLHUP:
                    mask += "h"
                if evt & select_module.POLLNVAL:
                    mask += "n"
                processed.append((fd, mask))
            return processed 

def readwrite(obj, flags):
    try:
        if flags & select.POLLIN:
            obj.handle_read_event()
        if flags & select.POLLOUT:
            obj.handle_write_event()
        if flags & select.POLLPRI:
            obj.handle_expt_event()
        if flags & (select.POLLHUP | select.POLLERR | select.POLLNVAL):
            obj.handle_close()
    except OSError as e:
        if e.args[0] not in _DISCONNECTED:
            obj.handle_error()
        else:
            obj.handle_close()
    except _reraised_exceptions:
        raise
    except:
        obj.handle_error() 

def poll(self, timeout):
            if timeout is not None:
                # convert from seconds to milliseconds
                timeout *= 1000
            changes = self._poll.poll(timeout)
            results = []
            for fd, events in changes:
                f = self._get_file_object(fd)
                if events & (select.POLLIN | select.POLLPRI):
                    results.append((f, POLLER_EVENT_READ))
                elif events & (select.POLLOUT):
                    results.append((f, POLLER_EVENT_WRITE))
                elif events & (select.POLLHUP):
                    results.append((f, POLLER_EVENT_HUP))
                elif events & (select.POLLERR | select.POLLNVAL):
                    results.append((f, POLLER_EVENT_ERROR))
            return results 

def readwrite(obj, flags):
    try:
        if flags & select.POLLIN:
            obj.handle_read_event()
        if flags & select.POLLOUT:
            obj.handle_write_event()
        if flags & select.POLLPRI:
            obj.handle_expt_event()
        if flags & (select.POLLHUP | select.POLLERR | select.POLLNVAL):
            obj.handle_close()
    except OSError as e:
        if e.args[0] not in _DISCONNECTED:
            obj.handle_error()
        else:
            obj.handle_close()
    except _reraised_exceptions:
        raise
    except:
        obj.handle_error() 

def read(self, size=1):
        """Read size bytes from the serial port. If a timeout is set it may
           return less characters as requested. With no timeout it will block
           until the requested number of bytes is read."""
        if self.fd is None: raise portNotOpenError
        read = bytearray()
        poll = select.poll()
        poll.register(self.fd, select.POLLIN|select.POLLERR|select.POLLHUP|select.POLLNVAL)
        if size > 0:
            while len(read) < size:
                # print "\tread(): size",size, "have", len(read)    #debug
                # wait until device becomes ready to read (or something fails)
                for fd, event in poll.poll(self._timeout*1000):
                    if event & (select.POLLERR|select.POLLHUP|select.POLLNVAL):
                        raise SerialException('device reports error (poll)')
                    #  we don't care if it is select.POLLIN or timeout, that's
                    #  handled below
                buf = os.read(self.fd, size - len(read))
                read.extend(buf)
                if ((self._timeout is not None and self._timeout >= 0) or 
                    (self._interCharTimeout is not None and self._interCharTimeout > 0)) and not buf:
                    break   # early abort on timeout
        return bytes(read) 

def _ensure_pipes(self):

        "Ensure that the channel is capable of communicating."

        if self.read_pipe is None or self.write_pipe is None:

            # Accept any incoming connections.

            endpoint, address = self.endpoint.accept()
            self.read_pipe = endpoint.makefile("rb", 0)
            self.write_pipe = endpoint.makefile("wb", 0)

            # Monitor the write pipe for error conditions.

            fileno = self.write_pipe.fileno()
            self.poller.register(fileno, select.POLLOUT | select.POLLHUP | select.POLLNVAL | select.POLLERR) 

def add_file(self, file, callback):
    logging.debug("IOManager adding file: %s", str(file))

    def add_handler(poller, callbacks):
      poller.register(
          file, select.POLLIN | select.POLLPRI | select.POLLERR | select.POLLHUP | select.POLLNVAL)
      callbacks[file.fileno()] = callback
      logging.debug("IOManager thread added file successfully")
      return True

    self.control_queue.put(add_handler)
    self._wake_io_thread()
    self.control_queue.join() 

def poll2(timeout=0.0, map=None):
    # Use the poll() support added to the select module in Python 2.0
    if map is None:
        map = socket_map
    if timeout is not None:
        # timeout is in milliseconds
        timeout = int(timeout*1000)
    pollster = select.poll()
    if map:
        for fd, obj in map.items():
            flags = 0
            if obj.readable():
                flags |= select.POLLIN | select.POLLPRI
            if obj.writable():
                flags |= select.POLLOUT
            if flags:
                # Only check for exceptions if object was either readable
                # or writable.
                flags |= select.POLLERR | select.POLLHUP | select.POLLNVAL
                pollster.register(fd, flags)
        try:
            r = pollster.poll(timeout)
        except select.error, err:
            if err.args[0] != EINTR:
                raise
            r = []
        for fd, flags in r:
            obj = map.get(fd)
            if obj is None:
                continue
            readwrite(obj, flags) 

def events_from_poll(self, events):
        ret = 0
        if events & select.POLLIN:
            ret |= libvirt.VIR_EVENT_HANDLE_READABLE
        if events & select.POLLOUT:
            ret |= libvirt.VIR_EVENT_HANDLE_WRITABLE
        if events & select.POLLNVAL:
            ret |= libvirt.VIR_EVENT_HANDLE_ERROR
        if events & select.POLLERR:
            ret |= libvirt.VIR_EVENT_HANDLE_ERROR
        if events & select.POLLHUP:
            ret |= libvirt.VIR_EVENT_HANDLE_HANGUP
        return ret 

def test_sends_hangups(self):
    pipe = PipeWrapper()
    event = threading.Event()

    def callback(flag):
      if flag != select.POLLHUP and flag != select.POLLNVAL:
        self.assertEqual(flag, select.POLLHUP | select.POLLNVAL)
      event.set()

    self.manager.add_file(pipe.reader, callback)
    pipe.writer.close()
    event.wait(1)
    self.assertTrue(event.is_set()) 

def ready(self, timeout=None):

        """
        Wait for a period of time specified by the optional 'timeout' in
        milliseconds (or until communication is possible) and return a list of
        channels which are ready to be read from.
        """

        fds = self.poller.poll(timeout)
        readables = []
        self.removed = []

        for fd, status in fds:
            channel = self.readables[fd]
            removed = 0

            # Remove ended/error channels.

            if status & (select.POLLHUP | select.POLLNVAL | select.POLLERR):
                self.remove(channel)
                self.removed.append(channel)
                removed = 1

            # Record readable channels.

            if status & select.POLLIN:
                if not (removed and self.autoclose):
                    readables.append(channel)

        return readables 

def readwrite(obj, flags):
    try:
        if flags & select.POLLIN:
            obj.handle_read_event()
        if flags & select.POLLOUT:
            obj.handle_write_event()
        if flags & select.POLLPRI:
            obj.handle_expt_event()
        if flags & (select.POLLHUP | select.POLLERR | select.POLLNVAL):
            obj.handle_close()
    except socket.error, e:
        if e.args[0] not in _DISCONNECTED:
            obj.handle_error()
        else:
            obj.handle_close() 

def readwrite(obj, flags):
    try:
        if flags & select.POLLIN:
            obj.handle_read_event()
        if flags & select.POLLOUT:
            obj.handle_write_event()
        if flags & select.POLLPRI:
            obj.handle_expt_event()
        if flags & (select.POLLHUP | select.POLLERR | select.POLLNVAL):
            obj.handle_close()
    except socket.error, e:
        if e.args[0] not in _DISCONNECTED:
            obj.handle_error()
        else:
            obj.handle_close() 

def step_impl(context):
    """Test that we have a correctly installed Burp Suite and the scanner driver available"""
    logging.getLogger("requests").setLevel(logging.WARNING)
    burpprocess = start_burp(context)

    # Send a message to headless-scanner-driver extension and wait for response.
    # Communicates to the scanner driver using a magical port number.
    # See https://github.com/F-Secure/headless-scanner-driver for additional documentation

    proxydict = {'http': 'http://' + context.burp_proxy_address,
                 'https': 'https://' + context.burp_proxy_address}
    try:
        requests.get("http://localhost:1111", proxies=proxydict)
    except requests.exceptions.RequestException as e:
        kill_subprocess(burpprocess)
        assert False, "Could not fetch scan item status over %s (%s). Is the proxy listener on?" % (
            context.burp_proxy_address, e)
    proxy_message = read_next_json(burpprocess)
    if proxy_message is None:
        kill_subprocess(burpprocess)
        assert False, "Timed out communicating to headless-scanner-driver " \
                      "extension over %s. Is something else running there?" \
                      % context.burp_proxy_address

    # Shut down Burp Suite. Again, see the scanner driver plugin docs for further info.

    poll = select.poll()
    poll.register(burpprocess.stdout, select.POLLNVAL | select.POLLHUP)  # pylint: disable-msg=E1101
    try:
        requests.get("http://localhost:1112", proxies=proxydict)
    except requests.exceptions.RequestException as e:
        kill_subprocess(burpprocess)
        assert False, "Could not fetch scan results over %s (%s)" % (context.burp_proxy_address, e)
    descriptors = poll.poll(10000)
    if descriptors == []:
        kill_subprocess(burpprocess)
        assert False, "Burp Suite clean exit took more than 10 seconds, killed"
    assert True 

def read(self, size=1):
        """\
        Read size bytes from the serial port. If a timeout is set it may
        return less characters as requested. With no timeout it will block
        until the requested number of bytes is read.
        """
        if not self.is_open:
            raise portNotOpenError
        read = bytearray()
        poll = select.poll()
        poll.register(self.fd, select.POLLIN | select.POLLERR | select.POLLHUP | select.POLLNVAL)
        if size > 0:
            while len(read) < size:
                # print "\tread(): size",size, "have", len(read)    #debug
                # wait until device becomes ready to read (or something fails)
                for fd, event in poll.poll(self._timeout * 1000):
                    if event & (select.POLLERR | select.POLLHUP | select.POLLNVAL):
                        raise SerialException('device reports error (poll)')
                    #  we don't care if it is select.POLLIN or timeout, that's
                    #  handled below
                buf = os.read(self.fd, size - len(read))
                read.extend(buf)
                if ((self._timeout is not None and self._timeout >= 0) or
                        (self._inter_byte_timeout is not None and self._inter_byte_timeout > 0)) and not buf:
                    break   # early abort on timeout
        return bytes(read) 

def poll2(timeout=0.0, map=None):
    # Use the poll() support added to the select module in Python 2.0
    if map is None:
        map = socket_map
    if timeout is not None:
        # timeout is in milliseconds
        timeout = int(timeout*1000)
    pollster = select.poll()
    if map:
        for fd, obj in map.items():
            flags = 0
            if obj.readable():
                flags |= select.POLLIN | select.POLLPRI
            # accepting sockets should not be writable
            if obj.writable() and not obj.accepting:
                flags |= select.POLLOUT
            if flags:
                # Only check for exceptions if object was either readable
                # or writable.
                flags |= select.POLLERR | select.POLLHUP | select.POLLNVAL
                pollster.register(fd, flags)
        try:
            r = pollster.poll(timeout)
        except select.error, err:
            if err.args[0] != EINTR:
                raise
            r = []
        for fd, flags in r:
            obj = map.get(fd)
            if obj is None:
                continue
            readwrite(obj, flags) 

def readwrite(obj, flags):
    try:
        if flags & select.POLLIN:
            obj.handle_read_event()
        if flags & select.POLLOUT:
            obj.handle_write_event()
        if flags & select.POLLPRI:
            obj.handle_expt_event()
        if flags & (select.POLLHUP | select.POLLERR | select.POLLNVAL):
            obj.handle_close()
    except socket.error, e:
        if e.args[0] not in _DISCONNECTED:
            obj.handle_error()
        else:
            obj.handle_close() 

def readwrite(obj, flags):
    try:
        if flags & select.POLLIN:
            obj.handle_read_event()
        if flags & select.POLLOUT:
            obj.handle_write_event()
        if flags & select.POLLPRI:
            obj.handle_expt_event()
        if flags & (select.POLLHUP | select.POLLERR | select.POLLNVAL):
            obj.handle_close()
    except socket.error, e:
        if e.args[0] not in _DISCONNECTED:
            obj.handle_error()
        else:
            obj.handle_close()