def create_device_stream(arg, allowed):
""" Create a device stream based on protocal string. """
argsplit = arg.split(':', 1)
if len(argsplit) == 1:
# use first allowed protocol as default
addr, val = allowed[0], argsplit[0]
elif len(argsplit) == 2:
addr, val = argsplit[0].upper(), argsplit[1]
else:
return None
if addr not in allowed:
return None
if addr == 'PRINTER':
stream = printer.PrinterStream(val)
elif addr == 'FILE':
try:
if not os.path.exists(val):
open(val, 'wb').close()
stream = open(val, 'r+b')
except (IOError, OSError) as e:
return None
elif addr == 'PARPORT':
# port can be e.g. /dev/parport0 on Linux or LPT1 on Windows. Just a number counting from 0 would also work.
stream = serial_socket.parallel_port(val)
elif addr == 'PORT':
# port can be e.g. /dev/ttyS1 on Linux or COM1 on Windows. Or anything supported by serial_for_url (RFC 2217 etc)
stream = serial_socket.serial_for_url(val)
elif addr == 'SOCKET':
stream = serial_socket.serial_for_url('socket://'+val)
else:
# File not found
raise error.RunError(53)
return stream
def __init__(self, arg, default_stream, flush_trigger):
""" Initialise LPTn: device. """
Device.__init__(self)
addr, val = parse_protocol_string(arg)
self.stream = default_stream
if (addr and addr not in self.allowed_protocols):
logging.warning('Could not attach %s to LPT device', arg)
elif addr == 'FILE':
try:
if not os.path.exists(val):
open(val, 'wb').close()
self.stream = open(val, 'r+b')
except (IOError, OSError) as e:
logging.warning('Could not attach file %s to LPT device: %s', val, str(e))
elif addr == 'PARPORT':
# port can be e.g. /dev/parport0 on Linux or LPT1 on Windows. Just a number counting from 0 would also work.
self.stream = serial_socket.parallel_port(val)
else:
# 'PRINTER' is default
self.stream = printer.PrinterStream(val)
if self.stream:
self.device_file = LPTFile(self.stream, flush_trigger)
self.device_file.flush_trigger = flush_trigger
