Python code coverage for Lib/telnetlib.py

#	count	content
1	n/a	r"""TELNET client class.
2	n/a
3	n/a	Based on RFC 854: TELNET Protocol Specification, by J. Postel and
4	n/a	J. Reynolds
5	n/a
6	n/a	Example:
7	n/a
8	n/a	>>> from telnetlib import Telnet
9	n/a	>>> tn = Telnet('www.python.org', 79) # connect to finger port
10	n/a	>>> tn.write(b'guido\r\n')
11	n/a	>>> print(tn.read_all())
12	n/a	Login Name TTY Idle When Where
13	n/a	guido Guido van Rossum pts/2 <Dec 2 11:10> snag.cnri.reston..
14	n/a
15	n/a	>>>
16	n/a
17	n/a	Note that read_all() won't read until eof -- it just reads some data
18	n/a	-- but it guarantees to read at least one byte unless EOF is hit.
19	n/a
20	n/a	It is possible to pass a Telnet object to a selector in order to wait until
21	n/a	more data is available. Note that in this case, read_eager() may return b''
22	n/a	even if there was data on the socket, because the protocol negotiation may have
23	n/a	eaten the data. This is why EOFError is needed in some cases to distinguish
24	n/a	between "no data" and "connection closed" (since the socket also appears ready
25	n/a	for reading when it is closed).
26	n/a
27	n/a	To do:
28	n/a	- option negotiation
29	n/a	- timeout should be intrinsic to the connection object instead of an
30	n/a	option on one of the read calls only
31	n/a
32	n/a	"""
33	n/a
34	n/a
35	n/a	# Imported modules
36	n/a	import sys
37	n/a	import socket
38	n/a	import selectors
39	n/a	from time import monotonic as _time
40	n/a
41	n/a	__all__ = ["Telnet"]
42	n/a
43	n/a	# Tunable parameters
44	n/a	DEBUGLEVEL = 0
45	n/a
46	n/a	# Telnet protocol defaults
47	n/a	TELNET_PORT = 23
48	n/a
49	n/a	# Telnet protocol characters (don't change)
50	n/a	IAC = bytes([255]) # "Interpret As Command"
51	n/a	DONT = bytes([254])
52	n/a	DO = bytes([253])
53	n/a	WONT = bytes([252])
54	n/a	WILL = bytes([251])
55	n/a	theNULL = bytes([0])
56	n/a
57	n/a	SE = bytes([240]) # Subnegotiation End
58	n/a	NOP = bytes([241]) # No Operation
59	n/a	DM = bytes([242]) # Data Mark
60	n/a	BRK = bytes([243]) # Break
61	n/a	IP = bytes([244]) # Interrupt process
62	n/a	AO = bytes([245]) # Abort output
63	n/a	AYT = bytes([246]) # Are You There
64	n/a	EC = bytes([247]) # Erase Character
65	n/a	EL = bytes([248]) # Erase Line
66	n/a	GA = bytes([249]) # Go Ahead
67	n/a	SB = bytes([250]) # Subnegotiation Begin
68	n/a
69	n/a
70	n/a	# Telnet protocol options code (don't change)
71	n/a	# These ones all come from arpa/telnet.h
72	n/a	BINARY = bytes([0]) # 8-bit data path
73	n/a	ECHO = bytes([1]) # echo
74	n/a	RCP = bytes([2]) # prepare to reconnect
75	n/a	SGA = bytes([3]) # suppress go ahead
76	n/a	NAMS = bytes([4]) # approximate message size
77	n/a	STATUS = bytes([5]) # give status
78	n/a	TM = bytes([6]) # timing mark
79	n/a	RCTE = bytes([7]) # remote controlled transmission and echo
80	n/a	NAOL = bytes([8]) # negotiate about output line width
81	n/a	NAOP = bytes([9]) # negotiate about output page size
82	n/a	NAOCRD = bytes([10]) # negotiate about CR disposition
83	n/a	NAOHTS = bytes([11]) # negotiate about horizontal tabstops
84	n/a	NAOHTD = bytes([12]) # negotiate about horizontal tab disposition
85	n/a	NAOFFD = bytes([13]) # negotiate about formfeed disposition
86	n/a	NAOVTS = bytes([14]) # negotiate about vertical tab stops
87	n/a	NAOVTD = bytes([15]) # negotiate about vertical tab disposition
88	n/a	NAOLFD = bytes([16]) # negotiate about output LF disposition
89	n/a	XASCII = bytes([17]) # extended ascii character set
90	n/a	LOGOUT = bytes([18]) # force logout
91	n/a	BM = bytes([19]) # byte macro
92	n/a	DET = bytes([20]) # data entry terminal
93	n/a	SUPDUP = bytes([21]) # supdup protocol
94	n/a	SUPDUPOUTPUT = bytes([22]) # supdup output
95	n/a	SNDLOC = bytes([23]) # send location
96	n/a	TTYPE = bytes([24]) # terminal type
97	n/a	EOR = bytes([25]) # end or record
98	n/a	TUID = bytes([26]) # TACACS user identification
99	n/a	OUTMRK = bytes([27]) # output marking
100	n/a	TTYLOC = bytes([28]) # terminal location number
101	n/a	VT3270REGIME = bytes([29]) # 3270 regime
102	n/a	X3PAD = bytes([30]) # X.3 PAD
103	n/a	NAWS = bytes([31]) # window size
104	n/a	TSPEED = bytes([32]) # terminal speed
105	n/a	LFLOW = bytes([33]) # remote flow control
106	n/a	LINEMODE = bytes([34]) # Linemode option
107	n/a	XDISPLOC = bytes([35]) # X Display Location
108	n/a	OLD_ENVIRON = bytes([36]) # Old - Environment variables
109	n/a	AUTHENTICATION = bytes([37]) # Authenticate
110	n/a	ENCRYPT = bytes([38]) # Encryption option
111	n/a	NEW_ENVIRON = bytes([39]) # New - Environment variables
112	n/a	# the following ones come from
113	n/a	# http://www.iana.org/assignments/telnet-options
114	n/a	# Unfortunately, that document does not assign identifiers
115	n/a	# to all of them, so we are making them up
116	n/a	TN3270E = bytes([40]) # TN3270E
117	n/a	XAUTH = bytes([41]) # XAUTH
118	n/a	CHARSET = bytes([42]) # CHARSET
119	n/a	RSP = bytes([43]) # Telnet Remote Serial Port
120	n/a	COM_PORT_OPTION = bytes([44]) # Com Port Control Option
121	n/a	SUPPRESS_LOCAL_ECHO = bytes([45]) # Telnet Suppress Local Echo
122	n/a	TLS = bytes([46]) # Telnet Start TLS
123	n/a	KERMIT = bytes([47]) # KERMIT
124	n/a	SEND_URL = bytes([48]) # SEND-URL
125	n/a	FORWARD_X = bytes([49]) # FORWARD_X
126	n/a	PRAGMA_LOGON = bytes([138]) # TELOPT PRAGMA LOGON
127	n/a	SSPI_LOGON = bytes([139]) # TELOPT SSPI LOGON
128	n/a	PRAGMA_HEARTBEAT = bytes([140]) # TELOPT PRAGMA HEARTBEAT
129	n/a	EXOPL = bytes([255]) # Extended-Options-List
130	n/a	NOOPT = bytes([0])
131	n/a
132	n/a
133	n/a	# poll/select have the advantage of not requiring any extra file descriptor,
134	n/a	# contrarily to epoll/kqueue (also, they require a single syscall).
135	n/a	if hasattr(selectors, 'PollSelector'):
136	n/a	_TelnetSelector = selectors.PollSelector
137	n/a	else:
138	n/a	_TelnetSelector = selectors.SelectSelector
139	n/a
140	n/a
141	n/a	class Telnet:
142	n/a
143	n/a	"""Telnet interface class.
144	n/a
145	n/a	An instance of this class represents a connection to a telnet
146	n/a	server. The instance is initially not connected; the open()
147	n/a	method must be used to establish a connection. Alternatively, the
148	n/a	host name and optional port number can be passed to the
149	n/a	constructor, too.
150	n/a
151	n/a	Don't try to reopen an already connected instance.
152	n/a
153	n/a	This class has many read_*() methods. Note that some of them
154	n/a	raise EOFError when the end of the connection is read, because
155	n/a	they can return an empty string for other reasons. See the
156	n/a	individual doc strings.
157	n/a
158	n/a	read_until(expected, [timeout])
159	n/a	Read until the expected string has been seen, or a timeout is
160	n/a	hit (default is no timeout); may block.
161	n/a
162	n/a	read_all()
163	n/a	Read all data until EOF; may block.
164	n/a
165	n/a	read_some()
166	n/a	Read at least one byte or EOF; may block.
167	n/a
168	n/a	read_very_eager()
169	n/a	Read all data available already queued or on the socket,
170	n/a	without blocking.
171	n/a
172	n/a	read_eager()
173	n/a	Read either data already queued or some data available on the
174	n/a	socket, without blocking.
175	n/a
176	n/a	read_lazy()
177	n/a	Read all data in the raw queue (processing it first), without
178	n/a	doing any socket I/O.
179	n/a
180	n/a	read_very_lazy()
181	n/a	Reads all data in the cooked queue, without doing any socket
182	n/a	I/O.
183	n/a
184	n/a	read_sb_data()
185	n/a	Reads available data between SB ... SE sequence. Don't block.
186	n/a
187	n/a	set_option_negotiation_callback(callback)
188	n/a	Each time a telnet option is read on the input flow, this callback
189	n/a	(if set) is called with the following parameters :
190	n/a	callback(telnet socket, command, option)
191	n/a	option will be chr(0) when there is no option.
192	n/a	No other action is done afterwards by telnetlib.
193	n/a
194	n/a	"""
195	n/a
196	n/a	def __init__(self, host=None, port=0,
197	n/a	timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
198	n/a	"""Constructor.
199	n/a
200	n/a	When called without arguments, create an unconnected instance.
201	n/a	With a hostname argument, it connects the instance; port number
202	n/a	and timeout are optional.
203	n/a	"""
204	n/a	self.debuglevel = DEBUGLEVEL
205	n/a	self.host = host
206	n/a	self.port = port
207	n/a	self.timeout = timeout
208	n/a	self.sock = None
209	n/a	self.rawq = b''
210	n/a	self.irawq = 0
211	n/a	self.cookedq = b''
212	n/a	self.eof = 0
213	n/a	self.iacseq = b'' # Buffer for IAC sequence.
214	n/a	self.sb = 0 # flag for SB and SE sequence.
215	n/a	self.sbdataq = b''
216	n/a	self.option_callback = None
217	n/a	if host is not None:
218	n/a	self.open(host, port, timeout)
219	n/a
220	n/a	def open(self, host, port=0, timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
221	n/a	"""Connect to a host.
222	n/a
223	n/a	The optional second argument is the port number, which
224	n/a	defaults to the standard telnet port (23).
225	n/a
226	n/a	Don't try to reopen an already connected instance.
227	n/a	"""
228	n/a	self.eof = 0
229	n/a	if not port:
230	n/a	port = TELNET_PORT
231	n/a	self.host = host
232	n/a	self.port = port
233	n/a	self.timeout = timeout
234	n/a	self.sock = socket.create_connection((host, port), timeout)
235	n/a
236	n/a	def __del__(self):
237	n/a	"""Destructor -- close the connection."""
238	n/a	self.close()
239	n/a
240	n/a	def msg(self, msg, *args):
241	n/a	"""Print a debug message, when the debug level is > 0.
242	n/a
243	n/a	If extra arguments are present, they are substituted in the
244	n/a	message using the standard string formatting operator.
245	n/a
246	n/a	"""
247	n/a	if self.debuglevel > 0:
248	n/a	print('Telnet(%s,%s):' % (self.host, self.port), end=' ')
249	n/a	if args:
250	n/a	print(msg % args)
251	n/a	else:
252	n/a	print(msg)
253	n/a
254	n/a	def set_debuglevel(self, debuglevel):
255	n/a	"""Set the debug level.
256	n/a
257	n/a	The higher it is, the more debug output you get (on sys.stdout).
258	n/a
259	n/a	"""
260	n/a	self.debuglevel = debuglevel
261	n/a
262	n/a	def close(self):
263	n/a	"""Close the connection."""
264	n/a	sock = self.sock
265	n/a	self.sock = None
266	n/a	self.eof = True
267	n/a	self.iacseq = b''
268	n/a	self.sb = 0
269	n/a	if sock:
270	n/a	sock.close()
271	n/a
272	n/a	def get_socket(self):
273	n/a	"""Return the socket object used internally."""
274	n/a	return self.sock
275	n/a
276	n/a	def fileno(self):
277	n/a	"""Return the fileno() of the socket object used internally."""
278	n/a	return self.sock.fileno()
279	n/a
280	n/a	def write(self, buffer):
281	n/a	"""Write a string to the socket, doubling any IAC characters.
282	n/a
283	n/a	Can block if the connection is blocked. May raise
284	n/a	OSError if the connection is closed.
285	n/a
286	n/a	"""
287	n/a	if IAC in buffer:
288	n/a	buffer = buffer.replace(IAC, IAC+IAC)
289	n/a	self.msg("send %r", buffer)
290	n/a	self.sock.sendall(buffer)
291	n/a
292	n/a	def read_until(self, match, timeout=None):
293	n/a	"""Read until a given string is encountered or until timeout.
294	n/a
295	n/a	When no match is found, return whatever is available instead,
296	n/a	possibly the empty string. Raise EOFError if the connection
297	n/a	is closed and no cooked data is available.
298	n/a
299	n/a	"""
300	n/a	n = len(match)
301	n/a	self.process_rawq()
302	n/a	i = self.cookedq.find(match)
303	n/a	if i >= 0:
304	n/a	i = i+n
305	n/a	buf = self.cookedq[:i]
306	n/a	self.cookedq = self.cookedq[i:]
307	n/a	return buf
308	n/a	if timeout is not None:
309	n/a	deadline = _time() + timeout
310	n/a	with _TelnetSelector() as selector:
311	n/a	selector.register(self, selectors.EVENT_READ)
312	n/a	while not self.eof:
313	n/a	if selector.select(timeout):
314	n/a	i = max(0, len(self.cookedq)-n)
315	n/a	self.fill_rawq()
316	n/a	self.process_rawq()
317	n/a	i = self.cookedq.find(match, i)
318	n/a	if i >= 0:
319	n/a	i = i+n
320	n/a	buf = self.cookedq[:i]
321	n/a	self.cookedq = self.cookedq[i:]
322	n/a	return buf
323	n/a	if timeout is not None:
324	n/a	timeout = deadline - _time()
325	n/a	if timeout < 0:
326	n/a	break
327	n/a	return self.read_very_lazy()
328	n/a
329	n/a	def read_all(self):
330	n/a	"""Read all data until EOF; block until connection closed."""
331	n/a	self.process_rawq()
332	n/a	while not self.eof:
333	n/a	self.fill_rawq()
334	n/a	self.process_rawq()
335	n/a	buf = self.cookedq
336	n/a	self.cookedq = b''
337	n/a	return buf
338	n/a
339	n/a	def read_some(self):
340	n/a	"""Read at least one byte of cooked data unless EOF is hit.
341	n/a
342	n/a	Return b'' if EOF is hit. Block if no data is immediately
343	n/a	available.
344	n/a
345	n/a	"""
346	n/a	self.process_rawq()
347	n/a	while not self.cookedq and not self.eof:
348	n/a	self.fill_rawq()
349	n/a	self.process_rawq()
350	n/a	buf = self.cookedq
351	n/a	self.cookedq = b''
352	n/a	return buf
353	n/a
354	n/a	def read_very_eager(self):
355	n/a	"""Read everything that's possible without blocking in I/O (eager).
356	n/a
357	n/a	Raise EOFError if connection closed and no cooked data
358	n/a	available. Return b'' if no cooked data available otherwise.
359	n/a	Don't block unless in the midst of an IAC sequence.
360	n/a
361	n/a	"""
362	n/a	self.process_rawq()
363	n/a	while not self.eof and self.sock_avail():
364	n/a	self.fill_rawq()
365	n/a	self.process_rawq()
366	n/a	return self.read_very_lazy()
367	n/a
368	n/a	def read_eager(self):
369	n/a	"""Read readily available data.
370	n/a
371	n/a	Raise EOFError if connection closed and no cooked data
372	n/a	available. Return b'' if no cooked data available otherwise.
373	n/a	Don't block unless in the midst of an IAC sequence.
374	n/a
375	n/a	"""
376	n/a	self.process_rawq()
377	n/a	while not self.cookedq and not self.eof and self.sock_avail():
378	n/a	self.fill_rawq()
379	n/a	self.process_rawq()
380	n/a	return self.read_very_lazy()
381	n/a
382	n/a	def read_lazy(self):
383	n/a	"""Process and return data that's already in the queues (lazy).
384	n/a
385	n/a	Raise EOFError if connection closed and no data available.
386	n/a	Return b'' if no cooked data available otherwise. Don't block
387	n/a	unless in the midst of an IAC sequence.
388	n/a
389	n/a	"""
390	n/a	self.process_rawq()
391	n/a	return self.read_very_lazy()
392	n/a
393	n/a	def read_very_lazy(self):
394	n/a	"""Return any data available in the cooked queue (very lazy).
395	n/a
396	n/a	Raise EOFError if connection closed and no data available.
397	n/a	Return b'' if no cooked data available otherwise. Don't block.
398	n/a
399	n/a	"""
400	n/a	buf = self.cookedq
401	n/a	self.cookedq = b''
402	n/a	if not buf and self.eof and not self.rawq:
403	n/a	raise EOFError('telnet connection closed')
404	n/a	return buf
405	n/a
406	n/a	def read_sb_data(self):
407	n/a	"""Return any data available in the SB ... SE queue.
408	n/a
409	n/a	Return b'' if no SB ... SE available. Should only be called
410	n/a	after seeing a SB or SE command. When a new SB command is
411	n/a	found, old unread SB data will be discarded. Don't block.
412	n/a
413	n/a	"""
414	n/a	buf = self.sbdataq
415	n/a	self.sbdataq = b''
416	n/a	return buf
417	n/a
418	n/a	def set_option_negotiation_callback(self, callback):
419	n/a	"""Provide a callback function called after each receipt of a telnet option."""
420	n/a	self.option_callback = callback
421	n/a
422	n/a	def process_rawq(self):
423	n/a	"""Transfer from raw queue to cooked queue.
424	n/a
425	n/a	Set self.eof when connection is closed. Don't block unless in
426	n/a	the midst of an IAC sequence.
427	n/a
428	n/a	"""
429	n/a	buf = [b'', b'']
430	n/a	try:
431	n/a	while self.rawq:
432	n/a	c = self.rawq_getchar()
433	n/a	if not self.iacseq:
434	n/a	if c == theNULL:
435	n/a	continue
436	n/a	if c == b"\021":
437	n/a	continue
438	n/a	if c != IAC:
439	n/a	buf[self.sb] = buf[self.sb] + c
440	n/a	continue
441	n/a	else:
442	n/a	self.iacseq += c
443	n/a	elif len(self.iacseq) == 1:
444	n/a	# 'IAC: IAC CMD [OPTION only for WILL/WONT/DO/DONT]'
445	n/a	if c in (DO, DONT, WILL, WONT):
446	n/a	self.iacseq += c
447	n/a	continue
448	n/a
449	n/a	self.iacseq = b''
450	n/a	if c == IAC:
451	n/a	buf[self.sb] = buf[self.sb] + c
452	n/a	else:
453	n/a	if c == SB: # SB ... SE start.
454	n/a	self.sb = 1
455	n/a	self.sbdataq = b''
456	n/a	elif c == SE:
457	n/a	self.sb = 0
458	n/a	self.sbdataq = self.sbdataq + buf[1]
459	n/a	buf[1] = b''
460	n/a	if self.option_callback:
461	n/a	# Callback is supposed to look into
462	n/a	# the sbdataq
463	n/a	self.option_callback(self.sock, c, NOOPT)
464	n/a	else:
465	n/a	# We can't offer automatic processing of
466	n/a	# suboptions. Alas, we should not get any
467	n/a	# unless we did a WILL/DO before.
468	n/a	self.msg('IAC %d not recognized' % ord(c))
469	n/a	elif len(self.iacseq) == 2:
470	n/a	cmd = self.iacseq[1:2]
471	n/a	self.iacseq = b''
472	n/a	opt = c
473	n/a	if cmd in (DO, DONT):
474	n/a	self.msg('IAC %s %d',
475	n/a	cmd == DO and 'DO' or 'DONT', ord(opt))
476	n/a	if self.option_callback:
477	n/a	self.option_callback(self.sock, cmd, opt)
478	n/a	else:
479	n/a	self.sock.sendall(IAC + WONT + opt)
480	n/a	elif cmd in (WILL, WONT):
481	n/a	self.msg('IAC %s %d',
482	n/a	cmd == WILL and 'WILL' or 'WONT', ord(opt))
483	n/a	if self.option_callback:
484	n/a	self.option_callback(self.sock, cmd, opt)
485	n/a	else:
486	n/a	self.sock.sendall(IAC + DONT + opt)
487	n/a	except EOFError: # raised by self.rawq_getchar()
488	n/a	self.iacseq = b'' # Reset on EOF
489	n/a	self.sb = 0
490	n/a	pass
491	n/a	self.cookedq = self.cookedq + buf[0]
492	n/a	self.sbdataq = self.sbdataq + buf[1]
493	n/a
494	n/a	def rawq_getchar(self):
495	n/a	"""Get next char from raw queue.
496	n/a
497	n/a	Block if no data is immediately available. Raise EOFError
498	n/a	when connection is closed.
499	n/a
500	n/a	"""
501	n/a	if not self.rawq:
502	n/a	self.fill_rawq()
503	n/a	if self.eof:
504	n/a	raise EOFError
505	n/a	c = self.rawq[self.irawq:self.irawq+1]
506	n/a	self.irawq = self.irawq + 1
507	n/a	if self.irawq >= len(self.rawq):
508	n/a	self.rawq = b''
509	n/a	self.irawq = 0
510	n/a	return c
511	n/a
512	n/a	def fill_rawq(self):
513	n/a	"""Fill raw queue from exactly one recv() system call.
514	n/a
515	n/a	Block if no data is immediately available. Set self.eof when
516	n/a	connection is closed.
517	n/a
518	n/a	"""
519	n/a	if self.irawq >= len(self.rawq):
520	n/a	self.rawq = b''
521	n/a	self.irawq = 0
522	n/a	# The buffer size should be fairly small so as to avoid quadratic
523	n/a	# behavior in process_rawq() above
524	n/a	buf = self.sock.recv(50)
525	n/a	self.msg("recv %r", buf)
526	n/a	self.eof = (not buf)
527	n/a	self.rawq = self.rawq + buf
528	n/a
529	n/a	def sock_avail(self):
530	n/a	"""Test whether data is available on the socket."""
531	n/a	with _TelnetSelector() as selector:
532	n/a	selector.register(self, selectors.EVENT_READ)
533	n/a	return bool(selector.select(0))
534	n/a
535	n/a	def interact(self):
536	n/a	"""Interaction function, emulates a very dumb telnet client."""
537	n/a	if sys.platform == "win32":
538	n/a	self.mt_interact()
539	n/a	return
540	n/a	with _TelnetSelector() as selector:
541	n/a	selector.register(self, selectors.EVENT_READ)
542	n/a	selector.register(sys.stdin, selectors.EVENT_READ)
543	n/a
544	n/a	while True:
545	n/a	for key, events in selector.select():
546	n/a	if key.fileobj is self:
547	n/a	try:
548	n/a	text = self.read_eager()
549	n/a	except EOFError:
550	n/a	print('* Connection closed by remote host *')
551	n/a	return
552	n/a	if text:
553	n/a	sys.stdout.write(text.decode('ascii'))
554	n/a	sys.stdout.flush()
555	n/a	elif key.fileobj is sys.stdin:
556	n/a	line = sys.stdin.readline().encode('ascii')
557	n/a	if not line:
558	n/a	return
559	n/a	self.write(line)
560	n/a
561	n/a	def mt_interact(self):
562	n/a	"""Multithreaded version of interact()."""
563	n/a	import _thread
564	n/a	_thread.start_new_thread(self.listener, ())
565	n/a	while 1:
566	n/a	line = sys.stdin.readline()
567	n/a	if not line:
568	n/a	break
569	n/a	self.write(line.encode('ascii'))
570	n/a
571	n/a	def listener(self):
572	n/a	"""Helper for mt_interact() -- this executes in the other thread."""
573	n/a	while 1:
574	n/a	try:
575	n/a	data = self.read_eager()
576	n/a	except EOFError:
577	n/a	print('* Connection closed by remote host *')
578	n/a	return
579	n/a	if data:
580	n/a	sys.stdout.write(data.decode('ascii'))
581	n/a	else:
582	n/a	sys.stdout.flush()
583	n/a
584	n/a	def expect(self, list, timeout=None):
585	n/a	"""Read until one from a list of a regular expressions matches.
586	n/a
587	n/a	The first argument is a list of regular expressions, either
588	n/a	compiled (re.RegexObject instances) or uncompiled (strings).
589	n/a	The optional second argument is a timeout, in seconds; default
590	n/a	is no timeout.
591	n/a
592	n/a	Return a tuple of three items: the index in the list of the
593	n/a	first regular expression that matches; the match object
594	n/a	returned; and the text read up till and including the match.
595	n/a
596	n/a	If EOF is read and no text was read, raise EOFError.
597	n/a	Otherwise, when nothing matches, return (-1, None, text) where
598	n/a	text is the text received so far (may be the empty string if a
599	n/a	timeout happened).
600	n/a
601	n/a	If a regular expression ends with a greedy match (e.g. '.*')
602	n/a	or if more than one expression can match the same input, the
603	n/a	results are undeterministic, and may depend on the I/O timing.
604	n/a
605	n/a	"""
606	n/a	re = None
607	n/a	list = list[:]
608	n/a	indices = range(len(list))
609	n/a	for i in indices:
610	n/a	if not hasattr(list[i], "search"):
611	n/a	if not re: import re
612	n/a	list[i] = re.compile(list[i])
613	n/a	if timeout is not None:
614	n/a	deadline = _time() + timeout
615	n/a	with _TelnetSelector() as selector:
616	n/a	selector.register(self, selectors.EVENT_READ)
617	n/a	while not self.eof:
618	n/a	self.process_rawq()
619	n/a	for i in indices:
620	n/a	m = list[i].search(self.cookedq)
621	n/a	if m:
622	n/a	e = m.end()
623	n/a	text = self.cookedq[:e]
624	n/a	self.cookedq = self.cookedq[e:]
625	n/a	return (i, m, text)
626	n/a	if timeout is not None:
627	n/a	ready = selector.select(timeout)
628	n/a	timeout = deadline - _time()
629	n/a	if not ready:
630	n/a	if timeout < 0:
631	n/a	break
632	n/a	else:
633	n/a	continue
634	n/a	self.fill_rawq()
635	n/a	text = self.read_very_lazy()
636	n/a	if not text and self.eof:
637	n/a	raise EOFError
638	n/a	return (-1, None, text)
639	n/a
640	n/a	def __enter__(self):
641	n/a	return self
642	n/a
643	n/a	def __exit__(self, type, value, traceback):
644	n/a	self.close()
645	n/a
646	n/a
647	n/a	def test():
648	n/a	"""Test program for telnetlib.
649	n/a
650	n/a	Usage: python telnetlib.py [-d] ... [host [port]]
651	n/a
652	n/a	Default host is localhost; default port is 23.
653	n/a
654	n/a	"""
655	n/a	debuglevel = 0
656	n/a	while sys.argv[1:] and sys.argv[1] == '-d':
657	n/a	debuglevel = debuglevel+1
658	n/a	del sys.argv[1]
659	n/a	host = 'localhost'
660	n/a	if sys.argv[1:]:
661	n/a	host = sys.argv[1]
662	n/a	port = 0
663	n/a	if sys.argv[2:]:
664	n/a	portstr = sys.argv[2]
665	n/a	try:
666	n/a	port = int(portstr)
667	n/a	except ValueError:
668	n/a	port = socket.getservbyname(portstr, 'tcp')
669	n/a	with Telnet() as tn:
670	n/a	tn.set_debuglevel(debuglevel)
671	n/a	tn.open(host, port, timeout=0.5)
672	n/a	tn.interact()
673	n/a
674	n/a	if __name__ == '__main__':
675	n/a	test()