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2.7 KiB

# -*- coding: utf-8 -*-
# TRX Toolkit
# CTRL interface implementation
# (C) 2016-2020 by Vadim Yanitskiy <axilirator@gmail.com>
# Contributions by sysmocom - s.f.m.c. GmbH
# All Rights Reserved
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# GNU General Public License for more details.
import logging as log
import time
from udp_link import UDPLink
class CTRLInterface(UDPLink):
def __init__(self, *udp_link_args):
UDPLink.__init__(self, *udp_link_args)
log.debug("Init TRXC interface (%s)" % self.desc_link())
# Do not delay RSP messages by default
self.rsp_delay_ms = 0
def handle_rx(self):
# Read data from socket
data, remote = self.sock.recvfrom(128)
data = data.decode()
if not self.verify_req(data):
log.error("Wrong data on TRXC interface")
# Attempt to parse a command
request = self.prepare_req(data)
rc = self.parse_cmd(request)
if type(rc) is tuple:
self.send_response(request, remote, rc[0], rc[1])
self.send_response(request, remote, rc)
def verify_req(self, data):
# Verify command signature
return data.startswith("CMD")
def prepare_req(self, data):
# Strip signature, paddings and \0
request = data[4:].strip().strip("\0")
# Split into a command and arguments
request = request.split(" ")
# Now we have something like ["TXTUNE", "941600"]
return request
# If va is True, the command can have variable number of arguments
def verify_cmd(self, request, cmd, argc, va = False):
# Check if requested command matches
if request[0] != cmd:
return False
# And has enough arguments
req_len = len(request[1:])
if not va and req_len != argc:
return False
elif va and req_len < argc:
return False
return True
def send_response(self, request, remote, response_code, params = None):
# Include status code, for example ["TXTUNE", "0", "941600"]
request.insert(1, str(response_code))
# Optionally append command specific parameters
if params is not None:
request += params
# Add the response signature, and join back to string
response = "RSP " + " ".join(request) + "\0"
# If configured, delay sending the RSP message
if self.rsp_delay_ms > 0:
time.sleep(self.rsp_delay_ms / 1000.0)
# Now we have something like "RSP TXTUNE 0 941600"
self.sendto(response, remote)
def parse_cmd(self, request):
raise NotImplementedError