def authenticate(self, cmd, password=None):
# I'm just implementing the authentication scheme designed in the
# protocol. Don't take this as any kind of assurance that it's secure.
data = protocol.read(self.f, 9)
assert data[:7] == 'PJLINK '
security = data[7]
if security == '0':
return None
data += protocol.read(self.f, 9)
assert security == '1'
assert data[8] == ' '
salt = data[9:17]
assert data[17] == '\r'
if password is None:
raise RuntimeError('projector needs a password')
if callable(password):
password = password()
pass_data = (salt + password).encode('utf-8')
pass_data_md5 = hashlib.md5(pass_data).hexdigest()
# we *must* send a command to complete the procedure,
# so we just get the power state.
cmd_data = protocol.to_binary(POWR_BODY, cmd)
self.f.write(pass_data_md5 + cmd_data)
self.f.flush()
# read the response, see if it's a failed auth
data = protocol.read(self.f, 7)
if data == 'PJLINK ':
# should be a failed auth if we get that
data += protocol.read(self.f, 5)
assert data == 'PJLINK ERRA\r'
# it definitely is
return False
# good auth, so we should get a reply to the command we sent
body, param = protocol.parse_response(self.f, data)
# make sure we got a sensible response back
assert body == POWR_BODY
if param in protocol.ERRORS:
raise ProjectorError(protocol.ERRORS[param])
# but we don't care about the value if we did
return param
def updateGyro():
protocol.usb.flushInput()
protocol.sendCommand('G')
angle = protocol.read(1)
if len(angle > 0):
global heading
heading = ord(angle[0]) - 128
def updateUltrasonic():
protocol.usb.flushInput()
protocol.sendCommand('M')
lrDistance = protocol.read(2)
if len(lrDistance) == 2:
global distanceLeft
global distanceRight
distanceLeft = ord(lrDistance[0])
distanceRight = ord(lrDistance[1])
def json(self):
if not hasattr(self, "parsed"):
self.parsed = read(self.msgType, self.data)
return self.parsed