mirror of
https://github.com/markqvist/Reticulum.git
synced 2024-12-15 02:44:33 -05:00
299 lines
11 KiB
Python
299 lines
11 KiB
Python
|
# MIT License - Copyright (c) 2024 Mark Qvist / unsigned.io
|
||
|
|
|
||
|
|
# This example illustrates creating a custom interface
|
||
|
|
# definition, that can be loaded and used by Reticulum at
|
||
|
|
# runtime. Any number of custom interfaces can be created
|
||
|
|
# and loaded. To use the interface place it in the folder
|
||
|
|
# ~/.reticulum/interfaces, and add an interface entry to
|
||
|
|
# your Reticulum configuration file similar to this:
|
||
|
|
|
||
|
|
# [[Example Custom Interface]]
|
||
|
|
# type = ExampleInterface
|
||
|
|
# enabled = no
|
||
|
|
# mode = gateway
|
||
|
|
# port = /dev/ttyUSB0
|
||
|
|
# speed = 115200
|
||
|
|
# databits = 8
|
||
|
|
# parity = none
|
||
|
|
# stopbits = 1
|
||
|
|
|
||
|
|
from time import sleep
|
||
|
|
import sys
|
||
|
|
import threading
|
||
|
|
import time
|
||
|
|
|
||
|
|
# This HDLC helper class is used by the interface
|
||
|
|
# to delimit and packetize data over the physical
|
||
|
|
# medium - in this case a serial connection.
|
||
|
|
class HDLC():
|
||
|
|
# This example interface packetizes data using
|
||
|
|
# simplified HDLC framing, similar to PPP
|
||
|
|
FLAG = 0x7E
|
||
|
|
ESC = 0x7D
|
||
|
|
ESC_MASK = 0x20
|
||
|
|
|
||
|
|
@staticmethod
|
||
|
|
def escape(data):
|
||
|
|
data = data.replace(bytes([HDLC.ESC]), bytes([HDLC.ESC, HDLC.ESC^HDLC.ESC_MASK]))
|
||
|
|
data = data.replace(bytes([HDLC.FLAG]), bytes([HDLC.ESC, HDLC.FLAG^HDLC.ESC_MASK]))
|
||
|
|
return data
|
||
|
|
|
||
|
|
# Let's define our custom interface class. It must
|
||
|
|
# be a sub-class of the RNS "Interface" class.
|
||
|
|
class ExampleInterface(Interface):
|
||
|
|
# All interface classes must define a default
|
||
|
|
# IFAC size, used in IFAC setup when the user
|
||
|
|
# has not specified a custom IFAC size. This
|
||
|
|
# option is specified in bytes.
|
||
|
|
DEFAULT_IFAC_SIZE = 8
|
||
|
|
|
||
|
|
# The following properties are local to this
|
||
|
|
# particular interface implementation.
|
||
|
|
owner = None
|
||
|
|
port = None
|
||
|
|
speed = None
|
||
|
|
databits = None
|
||
|
|
parity = None
|
||
|
|
stopbits = None
|
||
|
|
serial = None
|
||
|
|
|
||
|
|
# All Reticulum interfaces must have an __init__
|
||
|
|
# method that takes 2 positional arguments:
|
||
|
|
# The owner RNS Transport instance, and a dict
|
||
|
|
# of configuration values.
|
||
|
|
def __init__(self, owner, configuration):
|
||
|
|
|
||
|
|
# The following lines demonstrate handling
|
||
|
|
# potential dependencies required for the
|
||
|
|
# interface to function correctly.
|
||
|
|
import importlib
|
||
|
|
if importlib.util.find_spec('serial') != None:
|
||
|
|
import serial
|
||
|
|
else:
|
||
|
|
RNS.log("Using this interface requires a serial communication module to be installed.", RNS.LOG_CRITICAL)
|
||
|
|
RNS.log("You can install one with the command: python3 -m pip install pyserial", RNS.LOG_CRITICAL)
|
||
|
|
RNS.panic()
|
||
|
|
|
||
|
|
# We start out by initialising the super-class
|
||
|
|
super().__init__()
|
||
|
|
|
||
|
|
# To make sure the configuration data is in the
|
||
|
|
# correct format, we parse it through the following
|
||
|
|
# method on the generic Interface class. This step
|
||
|
|
# is required to ensure compatibility on all the
|
||
|
|
# platforms that Reticulum supports.
|
||
|
|
ifconf = Interface.get_config_obj(configuration)
|
||
|
|
|
||
|
|
# Read the interface name from the configuration
|
||
|
|
# and set it on our interface instance.
|
||
|
|
name = ifconf["name"]
|
||
|
|
self.name = name
|
||
|
|
|
||
|
|
# We read configuration parameters from the supplied
|
||
|
|
# configuration data, and provide default values in
|
||
|
|
# case any are missing.
|
||
|
|
port = ifconf["port"] if "port" in ifconf else None
|
||
|
|
speed = int(ifconf["speed"]) if "speed" in ifconf else 9600
|
||
|
|
databits = int(ifconf["databits"]) if "databits" in ifconf else 8
|
||
|
|
parity = ifconf["parity"] if "parity" in ifconf else "N"
|
||
|
|
stopbits = int(ifconf["stopbits"]) if "stopbits" in ifconf else 1
|
||
|
|
|
||
|
|
# In case no port is specified, we abort setup by
|
||
|
|
# raising an exception.
|
||
|
|
if port == None:
|
||
|
|
raise ValueError(f"No port specified for {self}")
|
||
|
|
|
||
|
|
# All interfaces must supply a hardware MTU value
|
||
|
|
# to the RNS Transport instance. This value should
|
||
|
|
# be the maximum data packet payload size that the
|
||
|
|
# underlying medium is capable of handling in all
|
||
|
|
# cases without any segmentation.
|
||
|
|
self.HW_MTU = 564
|
||
|
|
|
||
|
|
# We initially set the "online" property to false,
|
||
|
|
# since the interface has not actually been fully
|
||
|
|
# initialised and connected yet.
|
||
|
|
self.online = False
|
||
|
|
|
||
|
|
# In this case, we can also set the indicated bit-
|
||
|
|
# rate of the interface to the serial port speed.
|
||
|
|
self.bitrate = self.speed
|
||
|
|
|
||
|
|
# Configure internal properties on the interface
|
||
|
|
# according to the supplied configuration.
|
||
|
|
self.pyserial = serial
|
||
|
|
self.serial = None
|
||
|
|
self.owner = owner
|
||
|
|
self.port = port
|
||
|
|
self.speed = speed
|
||
|
|
self.databits = databits
|
||
|
|
self.parity = serial.PARITY_NONE
|
||
|
|
self.stopbits = stopbits
|
||
|
|
self.timeout = 100
|
||
|
|
|
||
|
|
if parity.lower() == "e" or parity.lower() == "even":
|
||
|
|
self.parity = serial.PARITY_EVEN
|
||
|
|
|
||
|
|
if parity.lower() == "o" or parity.lower() == "odd":
|
||
|
|
self.parity = serial.PARITY_ODD
|
||
|
|
|
||
|
|
# Since all required parameters are now configured,
|
||
|
|
# we will try opening the serial port.
|
||
|
|
try:
|
||
|
|
self.open_port()
|
||
|
|
except Exception as e:
|
||
|
|
RNS.log("Could not open serial port for interface "+str(self), RNS.LOG_ERROR)
|
||
|
|
raise e
|
||
|
|
|
||
|
|
# If opening the port succeeded, run any post-open
|
||
|
|
# configuration required.
|
||
|
|
if self.serial.is_open:
|
||
|
|
self.configure_device()
|
||
|
|
else:
|
||
|
|
raise IOError("Could not open serial port")
|
||
|
|
|
||
|
|
# Open the serial port with supplied configuration
|
||
|
|
# parameters and store a reference to the open port.
|
||
|
|
def open_port(self):
|
||
|
|
RNS.log("Opening serial port "+self.port+"...", RNS.LOG_VERBOSE)
|
||
|
|
self.serial = self.pyserial.Serial(
|
||
|
|
port = self.port,
|
||
|
|
baudrate = self.speed,
|
||
|
|
bytesize = self.databits,
|
||
|
|
parity = self.parity,
|
||
|
|
stopbits = self.stopbits,
|
||
|
|
xonxoff = False,
|
||
|
|
rtscts = False,
|
||
|
|
timeout = 0,
|
||
|
|
inter_byte_timeout = None,
|
||
|
|
write_timeout = None,
|
||
|
|
dsrdtr = False,
|
||
|
|
)
|
||
|
|
|
||
|
|
# The only thing required after opening the port
|
||
|
|
# is to wait a small amount of time for the
|
||
|
|
# hardware to initialise and then start a thread
|
||
|
|
# that reads any incoming data from the device.
|
||
|
|
def configure_device(self):
|
||
|
|
sleep(0.5)
|
||
|
|
thread = threading.Thread(target=self.read_loop)
|
||
|
|
thread.daemon = True
|
||
|
|
thread.start()
|
||
|
|
self.online = True
|
||
|
|
RNS.log("Serial port "+self.port+" is now open", RNS.LOG_VERBOSE)
|
||
|
|
|
||
|
|
|
||
|
|
# This method will be called from our read-loop
|
||
|
|
# whenever a full packet has been received over
|
||
|
|
# the underlying medium.
|
||
|
|
def process_incoming(self, data):
|
||
|
|
# Update our received bytes counter
|
||
|
|
self.rxb += len(data)
|
||
|
|
|
||
|
|
# And send the data packet to the Transport
|
||
|
|
# instance for processing.
|
||
|
|
self.owner.inbound(data, self)
|
||
|
|
|
||
|
|
# The running Reticulum Transport instance will
|
||
|
|
# call this method on the interface whenever the
|
||
|
|
# interface must transmit a packet.
|
||
|
|
def process_outgoing(self,data):
|
||
|
|
if self.online:
|
||
|
|
# First, escape and packetize the data
|
||
|
|
# according to HDLC framing.
|
||
|
|
data = bytes([HDLC.FLAG])+HDLC.escape(data)+bytes([HDLC.FLAG])
|
||
|
|
|
||
|
|
# Then write the framed data to the port
|
||
|
|
written = self.serial.write(data)
|
||
|
|
|
||
|
|
# Update the transmitted bytes counter
|
||
|
|
# and ensure that all data was written
|
||
|
|
self.txb += len(data)
|
||
|
|
if written != len(data):
|
||
|
|
raise IOError("Serial interface only wrote "+str(written)+" bytes of "+str(len(data)))
|
||
|
|
|
||
|
|
# This read loop runs in a thread and continously
|
||
|
|
# receives bytes from the underlying serial port.
|
||
|
|
# When a full packet has been received, it will
|
||
|
|
# be sent to the process_incoming methed, which
|
||
|
|
# will in turn pass it to the Transport instance.
|
||
|
|
def read_loop(self):
|
||
|
|
try:
|
||
|
|
in_frame = False
|
||
|
|
escape = False
|
||
|
|
data_buffer = b""
|
||
|
|
last_read_ms = int(time.time()*1000)
|
||
|
|
|
||
|
|
while self.serial.is_open:
|
||
|
|
if self.serial.in_waiting:
|
||
|
|
byte = ord(self.serial.read(1))
|
||
|
|
last_read_ms = int(time.time()*1000)
|
||
|
|
|
||
|
|
if (in_frame and byte == HDLC.FLAG):
|
||
|
|
in_frame = False
|
||
|
|
self.process_incoming(data_buffer)
|
||
|
|
elif (byte == HDLC.FLAG):
|
||
|
|
in_frame = True
|
||
|
|
data_buffer = b""
|
||
|
|
elif (in_frame and len(data_buffer) < self.HW_MTU):
|
||
|
|
if (byte == HDLC.ESC):
|
||
|
|
escape = True
|
||
|
|
else:
|
||
|
|
if (escape):
|
||
|
|
if (byte == HDLC.FLAG ^ HDLC.ESC_MASK):
|
||
|
|
byte = HDLC.FLAG
|
||
|
|
if (byte == HDLC.ESC ^ HDLC.ESC_MASK):
|
||
|
|
byte = HDLC.ESC
|
||
|
|
escape = False
|
||
|
|
data_buffer = data_buffer+bytes([byte])
|
||
|
|
|
||
|
|
else:
|
||
|
|
time_since_last = int(time.time()*1000) - last_read_ms
|
||
|
|
if len(data_buffer) > 0 and time_since_last > self.timeout:
|
||
|
|
data_buffer = b""
|
||
|
|
in_frame = False
|
||
|
|
escape = False
|
||
|
|
sleep(0.08)
|
||
|
|
|
||
|
|
except Exception as e:
|
||
|
|
self.online = False
|
||
|
|
RNS.log("A serial port error occurred, the contained exception was: "+str(e), RNS.LOG_ERROR)
|
||
|
|
RNS.log("The interface "+str(self)+" experienced an unrecoverable error and is now offline.", RNS.LOG_ERROR)
|
||
|
|
|
||
|
|
if RNS.Reticulum.panic_on_interface_error:
|
||
|
|
RNS.panic()
|
||
|
|
|
||
|
|
RNS.log("Reticulum will attempt to reconnect the interface periodically.", RNS.LOG_ERROR)
|
||
|
|
|
||
|
|
self.online = False
|
||
|
|
self.serial.close()
|
||
|
|
self.reconnect_port()
|
||
|
|
|
||
|
|
# This method handles serial port disconnects.
|
||
|
|
def reconnect_port(self):
|
||
|
|
while not self.online:
|
||
|
|
try:
|
||
|
|
time.sleep(5)
|
||
|
|
RNS.log("Attempting to reconnect serial port "+str(self.port)+" for "+str(self)+"...", RNS.LOG_VERBOSE)
|
||
|
|
self.open_port()
|
||
|
|
if self.serial.is_open:
|
||
|
|
self.configure_device()
|
||
|
|
except Exception as e:
|
||
|
|
RNS.log("Error while reconnecting port, the contained exception was: "+str(e), RNS.LOG_ERROR)
|
||
|
|
|
||
|
|
RNS.log("Reconnected serial port for "+str(self))
|
||
|
|
|
||
|
|
# Signal to Reticulum that this interface should
|
||
|
|
# not perform any ingress limiting.
|
||
|
|
def should_ingress_limit(self):
|
||
|
|
return False
|
||
|
|
|
||
|
|
# We must provide a string representation of this
|
||
|
|
# interface, that is used whenever the interface
|
||
|
|
# is printed in logs or external programs.
|
||
|
|
def __str__(self):
|
||
|
|
return "ExampleInterface["+self.name+"]"
|
||
|
|
|
||
|
|
# Finally, register the defined interface class as the
|
||
|
|
# target class for Reticulum to use as an interface
|
||
|
|
interface_class = ExampleInterface
|