Source code for Exscript.servers.telnetd

#
# Copyright (C) 2010-2017 Samuel Abels
# The MIT License (MIT)
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files
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# and to permit persons to whom the Software is furnished to do so,
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#
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"""
A Telnet server.
"""
from __future__ import absolute_import, print_function
import select
from copy import deepcopy
from .server import Server


[docs]class Telnetd(Server): """ A Telnet server. Usage:: device = VirtualDevice('myhost') daemon = Telnetd('localhost', 1234, device) device.add_command('ls', 'ok', prompt = True) device.add_command('exit', daemon.exit_command) daemon.start() # Start the server. daemon.exit() # Stop the server. daemon.join() # Wait until it terminates. """ def _recvline(self, conn): while not b'\n' in self.buf: r, w, x = select.select([conn], [], [], self.timeout) if not self.running: return None if not r: continue buf = conn.recv(1024) if not buf: self.running = False return None self.buf += buf.replace(b'\r\n', b'\n').replace(b'\r', b'\n') lines = self.buf.split(b'\n') self.buf = b'\n'.join(lines[1:]) return lines[0].decode(self.encoding) + '\n' def _handle_connection(self, conn): try: device = deepcopy(self.device) conn.send(device.init().encode('utf8')) while self.running: line = self._recvline(conn) if not line: continue response = self.device.do(line) if response: conn.send(response.encode('utf8')) except Exception as err: self._dbg(1, "_handle_connection(): %s" % err) finally: conn.close()