yrc.py [genesis]

yrc.py

1	"""
2	yrc: the Unix IRC client
3	Jacob Welsh
4	February 2017 - June 2019
5	"""
6
7	__version__ = '97 Kelvin'
8
9	# Knobs that one might conceivably want to tweak
10	DEFAULT_PORT = 6667
11	RECONN_DELAY_MIN = 4 # seconds
12	RECONN_DELAY_MAX = 256
13	PING_INTERVAL = 120
14	PING_TIMEOUT = 240
15	BUFLIST_WIDTH_MIN = len('* =#a$\|')
16	BUFLIST_WIDTH_STEP = 4
17	BUFLIST_WIDTH_START = BUFLIST_WIDTH_MIN + 3*BUFLIST_WIDTH_STEP
18	format_time = lambda tt: '%02d:%02d:%02d' % (tt.tm_hour, tt.tm_min, tt.tm_sec)
19
20	from os import (
21	O_APPEND, O_CREAT, O_NONBLOCK, O_WRONLY, chdir, close, getenv, mkdir,
22	open as os_open, pipe, read, strerror, write
23	)
24	from time import localtime, time
25	from errno import EAGAIN, EWOULDBLOCK, EEXIST, EINPROGRESS, EINTR, ENOENT
26	from select import select, error as SelectError
27	from signal import signal, SIG_DFL, SIGINT, SIGWINCH
28	from socket import socket, SOL_SOCKET, SO_ERROR, SHUT_RDWR, error as SockError
29
30	from fcntl import fcntl, F_GETFL, F_SETFL
31
32	import yterm as t
33	from yterm import NUL, BS, LF, CR, SO, SI, ESC, CSI, cseq
34	STDIN = 0
35	STDOUT = 1
36	self_pipe_rd, self_pipe_wr = pipe()
37
38	is_ctrl = lambda c: c < '\x20' or c == '\x7f'
39	ctrl = lambda c: chr(ord(c) ^ 0x40)
40
41	meta = lambda c: ESC + c
42
43	BEL = chr(7)
44	CRLF = CR + LF
45	C_X = ctrl('X')
46	C_G = ctrl('G') # aka BEL
47
48	# Cursor control keys
49	LEFT = t.CURSOR_BACK1
50	RIGHT = t.CURSOR_FORWARD1
51	UP = t.CURSOR_UP1
52	DOWN = t.CURSOR_DOWN1
53	HOME = t.CURSOR_HOME
54	# Not sure where these originate; vt220 perhaps? Seen on xterm, linux, screen
55	END = cseq('F')
56	INS = cseq('~', 2)
57	DEL = cseq('~', 3)
58	PGUP = cseq('~', 5)
59	PGDN = cseq('~', 6)
60	# Likewise; so far seen on linux, screen
61	LNX_HOME = cseq('~', 1)
62	LNX_END = cseq('~', 4)
63
64	GLOBAL_KEYS = {
65	C_X + 'n': 'buflist-switch-next',
66	C_X + 'p': 'buflist-switch-prev',
67	C_X + 'l': 'buflist-last-selected',
68	C_X + 'w': 'buflist-enter',
69	ctrl('L'): 'redraw',
70	}
71
72	PROMPT_KEYS = {
73	CR: 'prompt-submit',
74
75	INS: 'prompt-exit',
76
77	ctrl('F'): 'prompt-forward',
78	RIGHT: 'prompt-forward',
79
80	ctrl('B'): 'prompt-backward',
81	LEFT: 'prompt-backward',
82
83	ctrl('A'): 'prompt-start',
84	HOME: 'prompt-start',
85	LNX_HOME: 'prompt-start',
86
87	ctrl('E'): 'prompt-end',
88	END: 'prompt-end',
89	LNX_END: 'prompt-end',
90
91	ctrl('H'): 'prompt-backspace',
92	ctrl('?'): 'prompt-backspace',
93
94	ctrl('D'): 'prompt-delete',
95	DEL: 'prompt-delete',
96
97	meta('v'): 'scroll-up-page',
98	PGUP: 'scroll-up-page',
99
100	ctrl('V'): 'scroll-down-page',
101	PGDN: 'scroll-down-page',
102	}
103
104	BUFLIST_KEYS = {
105	CR: 'buflist-submit',
106
107	ctrl('N'): 'buflist-next',
108	DOWN: 'buflist-next',
109	'j': 'buflist-next',
110
111	ctrl('P'): 'buflist-prev',
112	UP: 'buflist-prev',
113	'k': 'buflist-prev',
114
115	meta('<'): 'buflist-top',
116	HOME: 'buflist-top',
117	LNX_HOME: 'buflist-top',
118	'g': 'buflist-top',
119
120	meta('>'): 'buflist-bottom',
121	END: 'buflist-bottom',
122	LNX_END: 'buflist-bottom',
123	'G': 'buflist-bottom',
124
125	'h': 'buflist-shrink',
126	LEFT: 'buflist-shrink',
127
128	'l': 'buflist-grow',
129	RIGHT: 'buflist-grow',
130	}
131
132	BUF_KEYS = {
133	'i': 'prompt-enter',
134	INS: 'prompt-enter',
135
136	meta('v'): 'scroll-up-page',
137	PGUP: 'scroll-up-page',
138	ctrl('B'): 'scroll-up-page',
139	'b': 'scroll-up-page',
140
141	ctrl('V'): 'scroll-down-page',
142	PGDN: 'scroll-down-page',
143	ctrl('F'): 'scroll-down-page',
144	'f': 'scroll-down-page',
145	' ': 'scroll-down-page',
146
147	ctrl('P'): 'scroll-up-line',
148	UP: 'scroll-up-line',
149	'k': 'scroll-up-line',
150
151	ctrl('N'): 'scroll-down-line',
152	DOWN: 'scroll-down-line',
153	'j': 'scroll-down-line',
154
155	meta('<'): 'scroll-top',
156	HOME: 'scroll-top',
157	LNX_HOME: 'scroll-top',
158	'g': 'scroll-top',
159
160	meta('>'): 'scroll-bottom',
161	END: 'scroll-bottom',
162	LNX_END: 'scroll-bottom',
163	'G': 'scroll-bottom',
164	}
165
166	CMD_ABBREVS = {
167	'c': 'connect',
168	'd': 'disconnect',
169	'j': 'join',
170	'k': 'kick',
171	'l': 'list',
172	'm': 'mode',
173	'n': 'nick',
174	'nam': 'names',
175	'p': 'part',
176	'q': 'quit',
177	's': 'send',
178	't': 'topic',
179	'st': 'set-topic',
180	'w': 'whois',
181	'ww': 'whowas',
182	'x': 'close',
183	'xn': 'close-net',
184	}
185
186	# file.write can barf up EINTR and unclear how to retry due to buffering. Nuts.
187	def write_all(fd, s):
188	n = 0
189	while n < len(s):
190	try:
191	n += write(fd, s[n:])
192	except EnvironmentError, e:
193	if e.errno != EINTR:
194	raise
195
196	out_buf = bytearray()
197	write_out = out_buf.extend
198	def flush_out():
199	write_all(STDOUT, out_buf)
200	del out_buf[:]
201
202	# MLtronics
203	def variant(vtype, name, nargs):
204	tag = (vtype, len(vtype), name)
205	def cons(*args):
206	if len(args) != nargs:
207	raise TypeError('%s takes %d args (%d given)'
208	% (name, nargs, len(args)))
209	return (tag, args)
210	vtype.append((name, cons))
211	return cons
212
213	variant_name = lambda val: val[0][2]
214	variant_args = lambda val: val[1]
215
216	def matcher(vtype, cases):
217	def receiver(name, cons):
218	for case, recv in cases:
219	if case is cons:
220	return recv
221	raise TypeError('missing case %s' % name)
222	tbl = [receiver(name, cons) for name, cons in vtype]
223	def match(val):
224	tag, args = val
225	if tag[0] is not vtype:
226	raise TypeError
227	return tbl[tag[1]](*args)
228	return match
229
230	message = []
231	m_privmsg = variant(message, 'PRIVMSG', 2)
232	m_notice = variant(message, 'NOTICE', 2)
233	m_join = variant(message, 'JOIN', 2)
234	m_part = variant(message, 'PART', 3)
235	m_quit = variant(message, 'QUIT', 2)
236	m_nick = variant(message, 'NICK', 2)
237	m_kick = variant(message, 'KICK', 4) # kick of specified user
238	m_kicked = variant(message, 'KICKED', 3) # kick of self
239	m_topic = variant(message, 'TOPIC', 2) # unifies TOPIC and RPL_(NO)TOPIC
240	m_chantopic = variant(message, 'CHANTOPIC', 3) # for unjoined channels
241	m_mode = variant(message, 'MODE', 2)
242	m_chanmode = variant(message, 'CHANMODE', 3)
243	m_names = variant(message, 'NAMES', 3)
244	m_endnames = variant(message, 'ENDNAMES', 2)
245	m_error = variant(message, 'ERROR', 2) # ERROR from server
246	m_client = variant(message, 'CLIENT', 1) # generated by client, not logged
247	m_server = variant(message, 'SERVER', 2) # catch-all for other server msgs
248
249	scr_height = None
250	scr_width = None
251
252	def sequence(*thunks):
253	def run():
254	for f in thunks:
255	f()
256	return run
257
258	def flatten(iterables):
259	for it in iterables:
260	for val in it:
261	yield val
262
263	def char_range(pair):
264	a, b = pair
265	return ''.join(map(chr, range(ord(a), ord(b) + 1)))
266
267	def partition(l, pred):
268	left = []
269	right = []
270	for elem in l:
271	if pred(elem):
272	left.append(elem)
273	else:
274	right.append(elem)
275	return left, right
276
277	def split_pair(s, sep=' '):
278	pair = s.split(sep, 1)
279	if len(pair) == 1:
280	pair.append('')
281	return pair
282
283	def make_encoder(f):
284	tbl = [f(i) for i in range(0x100)]
285	return lambda s: ''.join(tbl[ord(c)] for c in s)
286
287	# Non-invertible terminal sanitizing
288	asciify = make_encoder(lambda i:
289	'^' + ctrl(chr(i)) if i < 0x20 or i == 0x7f
290	else chr(i) if 0x20 <= i <= 0x7e
291	else '\\x%X' % i)
292
293	# Uglier, injective encoding for file names
294	fs_encode = make_encoder(lambda i:
295	chr(i) if 0x20 <= i <= 0x7e and chr(i) not in './%'
296	else '%' + ('%02X' % i))
297
298	make_casemapper = lambda upper_bound: make_encoder(lambda i:
299	chr(i + 0x20) if 0x41 <= i <= upper_bound
300	else chr(i))
301
302	# We currently support only the original IRC case mapping (as implemented, not
303	# as specified; one of many howlers in the RFC). The RPL_ISUPPORT reply that
304	# some servers use to advertise alternate mappings was specified in a draft
305	# long since expired
306	# (http://www.irc.org/tech_docs/draft-brocklesby-irc-isupport-03.txt). Besides,
307	# a case-insensitive protocol that can't agree on what "case" means is
308	# preposterous. This is an IRC client; if a server does not behave like an IRC
309	# server, it doesn't fall to us to decipher its nonsense.
310
311	IRC_CASEMAP = {'rfc1459': make_casemapper(0x5e)}
312
313	casemap_ascii = make_casemapper(0x5a)
314
315	clip = lambda min_, max_, x: max(min_, min(max_, x))
316	clip_to = lambda l, i: clip(0, len(l) - 1, i)
317	get_clipped = lambda l, i: l[clip_to(l, i)]
318
319	def clip_str(s, width):
320	if width == 0:
321	return ''
322	if len(s) > width:
323	return '%s$' % s[:width - 1]
324	return s
325
326	def pad_or_clip_str(s, width, pad=' '):
327	if len(s) < width:
328	return s + pad*(width - len(s))
329	return clip_str(s, width)
330
331	def wrap(line, width, sep=' '):
332	start = 0
333	lines = []
334	while start + width < len(line):
335	end = start + width
336	cut = line.rfind(sep, start, end + 1)
337	if cut == -1:
338	lines.append(line[start:end])
339	start = end
340	else:
341	lines.append(line[start:cut])
342	start = cut + 1
343	lines.append(line[start:])
344	return lines
345
346	def is_digit(c):
347	return '0' <= c <= '9'
348
349	def parse_address(addr):
350	addr = addr.rsplit(':', 1)
351	host = addr[0]
352	if len(addr) == 1:
353	port = DEFAULT_PORT
354	else:
355	port = addr[1]
356	if not all(map(is_digit, port)):
357	raise ValueError('port not a positive integer: %r' % port)
358	port = int(port)
359	if port >= 2**16:
360	raise ValueError('port out of range: %d' % port)
361	return host, port
362
363	format_address = lambda host_port: '%s:%d' % host_port
364
365	int_of_bytes = lambda b: reduce(lambda acc, byte: acc*256 + ord(byte), b, 0)
366
367	def rand_int(n):
368	"""Get a random integer from 0 (inclusive) to n (exclusive) using the
369	system's nonblocking entropy pool. More-or-less deterministic run time, at
370	the cost of a small modulo bias."""
371	nbytes = (n.bit_length() + 7) / 8
372	with open('/dev/urandom', 'rb') as f:
373	return int_of_bytes(f.read(2*nbytes)) % n
374
375	#
376	# Binary min-heap, used as priority queue for scheduling
377	#
378
379	def heap_insert(h, key, value):
380	h.append((key, value))
381	# Percolate up
382	i = len(h) - 1
383	while i > 0:
384	i_parent = (i - 1)/2
385	item = h[i]
386	parent = h[i_parent]
387	if parent[0] <= item[0]:
388	break
389	h[i] = parent
390	h[i_parent] = item
391	i = i_parent
392
393	heap_peek = lambda h: h[0]
394
395	def heap_extract(h):
396	if len(h) == 1:
397	return h.pop()
398	result = h[0]
399	h[0] = h.pop()
400	# Percolate down
401	i = 0
402	while True:
403	i_child = 2*i + 1
404	if i_child >= len(h):
405	break
406	i_right = i_child + 1
407	if i_right < len(h) and h[i_right][0] < h[i_child][0]:
408	i_child = i_right
409	item = h[i]
410	child = h[i_child]
411	if item[0] <= child[0]:
412	break
413	h[i] = child
414	h[i_child] = item
415	i = i_child
416	return result
417
418	# purely for testing
419	def heapsort(iterable):
420	h = []
421	for item in iterable:
422	heap_insert(h, item, None)
423	while h:
424	yield heap_extract(h)[0]
425
426	#
427	# Config
428	#
429
430	def safe_filename(name):
431	return '/' not in name and name not in ('', '.', '..')
432
433	def get_config(key, paths=(()), default=None):
434	assert safe_filename(key)
435	for path in paths:
436	assert all(map(safe_filename, path))
437	fspath = []
438	fspath.extend(path)
439	fspath.append(key)
440	try:
441	with open('/'.join(fspath), 'rb') as f:
442	return f.read().rstrip('\n')
443	except EnvironmentError, e:
444	if e.errno != ENOENT:
445	error(e)
446	return default
447
448	def config_lines(text):
449	if text is None:
450	return None
451	lines = text.split('\n')
452	lines = [l.strip() for l in lines if not l.startswith('#')]
453	lines = [l for l in lines if len(l) > 0]
454	return lines if lines else None
455
456	#
457	# UI stuff
458	#
459
460	class CommandError(Exception):
461	pass
462
463	commands = {}
464	def command(name, min_args=0, max_args=None, extended_arg=False):
465	if max_args is None:
466	max_args = min_args
467	def register(func):
468	if name in commands:
469	raise ValueError('duplicate command %s' % name)
470	def run(arg_str=''):
471	args = []
472	while len(args) != max_args:
473	arg, arg_str = split_pair(arg_str.lstrip())
474	if arg == '':
475	break
476	args.append(arg)
477	arg_str = arg_str.lstrip()
478	if extended_arg:
479	args.append(arg_str)
480	elif arg_str:
481	raise CommandError('%s: too many arguments' % name)
482	if len(args) < min_args:
483	raise CommandError('%s: too few arguments' % name)
484	return func(*args)
485	commands[name] = run
486	return func
487	return register
488
489	def check_command_dicts(dicts):
490	for d in dicts:
491	for cmd in d.itervalues():
492	assert cmd in commands, cmd
493
494	def run_command(line):
495	cmd, args = split_pair(line)
496	cmd = CMD_ABBREVS.get(cmd, cmd)
497	func = commands.get(cmd)
498	if func is None:
499	raise CommandError('bad command: %s' % cmd)
500	return func(args)
501
502	flags = [False]*12
503	_getf = lambda i: (lambda: flags[i])
504	_setf = lambda i: (lambda: flags.__setitem__(i, True))
505	_clrf = lambda i: (lambda: flags.__setitem__(i, False))
506
507	refresh_flag = _getf(0)
508	schedule_refresh = _setf(0)
509	refresh_done = _clrf(0)
510
511	redraw_flag = _getf(1)
512	schedule_redraw = _setf(1)
513	redraw_done = _clrf(1)
514
515	buflist_draw_flag = _getf(2)
516	schedule_buflist_draw = _setf(2)
517	buflist_draw_done = _clrf(2)
518
519	buf_draw_flag = _getf(3)
520	schedule_buf_draw = _setf(3)
521	buf_draw_done = _clrf(3)
522
523	prompt_draw_flag = _getf(4)
524	schedule_prompt_draw = _setf(4)
525	prompt_draw_done = _clrf(4)
526
527	status_draw_flag = _getf(5)
528	schedule_status_draw = _setf(5)
529	status_draw_done = _clrf(5)
530
531	quit_flag = _getf(6)
532	schedule_quit = _setf(6)
533
534	# 7-8: available
535
536	buflist_flag = _getf(9)
537	buflist_enter = _setf(9)
538	buflist_exit = _clrf(9)
539
540	prompt_flag = _getf(10)
541	prompt_enter = _setf(10)
542	prompt_exit = _clrf(10)
543
544	ping_draw_flag = _getf(11)
545	set_ping_draw = _setf(11)
546	clr_ping_draw = _clrf(11)
547
548	new_buf = lambda name, parent, title: [name, parent, title, 0, [], 0, True]
549
550	buf_name = lambda b: b[0]
551	buf_parent = lambda b: b[1]
552	buf_title = lambda b: b[2]
553	buf_vscroll = lambda b: b[3]
554	buf_lines = lambda b: b[4]
555	buf_num_read = lambda b: b[5]
556	buf_unread = lambda b: len(buf_lines(b)) - buf_num_read(b)
557	buf_at_end = lambda b: b[6]
558
559	buf_set_title = lambda b, title: b.__setitem__(2, title)
560	buf_set_vscroll = lambda b, i: b.__setitem__(3, clip_to(buf_lines(b), i))
561	buf_set_num_read = lambda b, n: b.__setitem__(5, max(buf_num_read(b), n))
562	buf_set_at_end = lambda b: b.__setitem__(6, True)
563	buf_clr_at_end = lambda b: b.__setitem__(6, False)
564
565	format_buf_msg = matcher(message, (
566	(m_privmsg, lambda sender, msg: '<%s> %s' % (sender, msg)),
567	(m_server, lambda sender, msg: '<%s> %s' % (sender, msg)),
568	(m_notice, lambda sender, msg: '<-%s-> %s' % (sender, msg)),
569	(m_join, lambda sender, chan: '%s joins %s' % (sender, chan)),
570	(m_part, lambda sender, chan, msg: '%s parts %s [%s]'
571	% (sender, chan, msg)),
572	(m_quit, lambda sender, msg: '%s quits [%s]' % (sender, msg)),
573	(m_nick, lambda sender, nick: '%s is now known as %s' % (sender, nick)),
574	(m_kick, lambda sender, chan, name, msg: '%s kicked from %s by %s [%s]'
575	% (name, chan, sender, msg)),
576	(m_kicked, lambda sender, chan, msg: 'kicked from %s by %s [%s]'
577	% (chan, sender, msg)),
578	(m_topic, lambda sender, topic:
579	'%s sets topic to %s' % (sender, topic)
580	if topic else
581	'%s removes topic' % sender),
582	(m_chantopic, lambda sender, chan, topic:
583	'<%s> Topic for %s: %s' % (sender, chan, topic)
584	if topic is not None else
585	'<%s> No topic for %s' % (sender, chan)),
586	(m_mode, lambda sender, modes: 'MODE %s by %s' % (modes, sender)),
587	(m_chanmode, lambda sender, chan, modes: 'MODE %s on %s by %s'
588	% (modes, chan, sender)),
589	(m_names, lambda sender, chan, names: '<%s> NAMES in %s: %s'
590	% (sender, chan, names)),
591	(m_endnames, lambda sender, chan: '<%s> end NAMES in %s'
592	% (sender, chan)),
593	(m_error, lambda sender, msg: '<%s> server error: %s' % (sender, msg)),
594	(m_client, lambda msg: msg)))
595
596	def buf_log_msg(buf, m):
597	buf_lines(buf).append(format_time(localtime()) + ' ' + format_buf_msg(m))
598	schedule_buflist_draw() # for unread counts
599	if buf is cur_buf and buf_at_end(buf):
600	schedule_buf_draw()
601
602	def buf_privmsg(buf, msg):
603	if buf_parent(buf) is None:
604	raise CommandError("can't send messages here")
605	conn_privmsg(buf_registered_conn(buf), buf_name(buf), msg)
606
607	def render_lines(lines, width, start, row_limit):
608	"""Returns list of wrapped line lists, and the number of complete source
609	lines in the output"""
610	rows = 0
611	groups = []
612	while rows < row_limit and start < len(lines):
613	msg = lines[start]
614	group = wrap(asciify(msg), width)
615	rows += len(group)
616	if rows > row_limit:
617	group = group[:row_limit - rows]
618	groups.append(group)
619	return groups, len(groups) - 1
620	groups.append(group)
621	start += 1
622	return groups, len(groups)
623
624	def check_buf_at_end():
625	width = scr_width - buflist_width()
626	height = scr_height - 3
627	if height < 1 or width < 1:
628	return
629	lines = buf_lines(cur_buf)
630	scroll = buf_vscroll(cur_buf)
631	lines_shown = render_lines(lines, width, scroll, height)[1]
632	if scroll + lines_shown == len(lines):
633	buf_set_at_end(cur_buf)
634	else:
635	buf_clr_at_end(cur_buf)
636
637	def buf_draw(buf):
638	if scr_height < 2:
639	return
640	schedule_refresh()
641	write_out(t.CURSOR_HOME)
642	write_out(t.render((t.A_REVERSE,
643	pad_or_clip_str(asciify(buf_title(buf)), scr_width))))
644	left_column = buflist_width() + 1
645	width = scr_width - buflist_width()
646	top_row = 2
647	height = scr_height - 3
648	if height < 1 or width < 1:
649	return
650	lines = buf_lines(buf)
651	while True:
652	scroll = buf_vscroll(buf)
653	groups, lines_shown = render_lines(lines, width, scroll, height)
654	lines_shown += scroll
655	if lines_shown == len(lines):
656	buf_set_at_end(buf)
657	break
658	if not buf_at_end(buf):
659	break
660	# Was at end until now: autoscroll
661	if scroll + 1 == len(lines):
662	break # Couldn't even fit one complete line
663	buf_set_vscroll(buf, max(scroll + 1, len(lines) - height))
664	row = 0
665	for row, text in enumerate(flatten(groups)):
666	write_out(t.cursor_pos(top_row + row, left_column) + text)
667	if len(text) != width:
668	write_out(t.ERASE_LINE_TO_END)
669	for row in range(row + 1, height):
670	write_out(t.cursor_pos(top_row + row, left_column))
671	write_out(t.ERASE_LINE_TO_END)
672	buf_set_num_read(buf, lines_shown)
673	buf_draw_done()
674
675	cur_buf = new_buf('yrc', None, 'yrc general messages')
676	buffers = [cur_buf]
677	buffer_index = {}
678
679	is_child_of = lambda parent: lambda buf: buf_parent(buf) is parent
680
681	def sort_buffers():
682	global buffers
683	schedule_buflist_draw()
684	# "yrc" is always first
685	acc, buffers = buffers[:1], buffers[1:]
686	roots, buffers = partition(buffers, is_child_of(None))
687	roots.sort(key=buf_name)
688	for root in roots:
689	children, buffers = partition(buffers, is_child_of(root))
690	children.sort(key=buf_name)
691	acc.append(root)
692	acc.extend(children)
693	buffers = acc
694	buffer_index.clear()
695	for b in buffers:
696	parent = buf_parent(b)
697	parent_name = buf_name(parent) if parent else None
698	buffer_index[(buf_name(b), parent_name)] = b
699
700	def get_buf(name, parent_name):
701	try:
702	return buffer_index[(name, parent_name)]
703	except KeyError:
704	if parent_name is None:
705	parent = None
706	title = 'Network messages: %s' % name
707	else:
708	parent = get_buf(parent_name, None)
709	title = name if is_chan(name) else 'Private messages: %s' % name
710	b = new_buf(name, parent, title)
711	buffers.append(b)
712	sort_buffers()
713	return b
714
715	def find_buf(buf):
716	for i, b in enumerate(buffers):
717	if b is buf:
718	return i
719	raise ValueError("not in buffer list")
720
721	def close_buf(buf):
722	i = find_buf(buf)
723	assert i > 0
724	prev = buffers[i - 1]
725	buflist_set_cursor(prev)
726	last = buflist_last()
727	if last is buf: # not sure if this is possible but just in case
728	last = prev
729	buflist_select(prev)
730	buflist_set_last(last)
731	parent = buf_parent(buf)
732	parent_name = buf_name(parent) if parent else None
733	del buffer_index[(buf_name(buf), parent_name)]
734	buffers.pop(i)
735
736	command('scroll-down-page')(sequence(
737	schedule_buf_draw,
738	schedule_buflist_draw, # update unread counts
739	lambda: buf_set_vscroll(cur_buf, buf_vscroll(cur_buf) + (scr_height-3)/2)))
740
741	command('scroll-up-page')(sequence(
742	schedule_buf_draw,
743	lambda: buf_set_vscroll(cur_buf, buf_vscroll(cur_buf) - (scr_height-3)/2),
744	check_buf_at_end)) # stop autoscrolling if no longer at end
745
746	command('scroll-down-line')(sequence(
747	schedule_buf_draw,
748	schedule_buflist_draw,
749	lambda: buf_set_vscroll(cur_buf, buf_vscroll(cur_buf) + 1)))
750
751	command('scroll-up-line')(sequence(
752	schedule_buf_draw,
753	lambda: buf_set_vscroll(cur_buf, buf_vscroll(cur_buf) - 1),
754	check_buf_at_end))
755
756	command('scroll-bottom')(sequence(
757	schedule_buf_draw,
758	schedule_buflist_draw,
759	lambda: buf_set_vscroll(cur_buf, len(buf_lines(cur_buf)))))
760
761	command('scroll-top')(sequence(
762	schedule_buf_draw,
763	lambda: buf_set_vscroll(cur_buf, 0),
764	check_buf_at_end))
765
766	def info(msg, buf=None):
767	buf_log_msg(buf or buffers[0], m_client(msg))
768
769	def error(msg_or_exc, buf=None):
770	buf_log_msg(buf or buffers[0], m_client('ERROR: ' + str(msg_or_exc)))
771
772	prompt = [[], 0, 0, 1]
773
774	prompt_chars = lambda: prompt[0]
775	prompt_cursor = lambda: prompt[1]
776	prompt_hscroll = lambda: prompt[2]
777	prompt_cursor_column = lambda: prompt[3]
778
779	def prompt_clear():
780	schedule_prompt_draw()
781	prompt[0] = []
782	prompt_set_cursor(0)
783	prompt_set_hscroll(0)
784
785	def prompt_set_cursor(c):
786	schedule_prompt_draw()
787	if 0 <= c <= len(prompt_chars()):
788	prompt[1] = c
789	return True
790	return False
791
792	def prompt_set_hscroll(s):
793	schedule_prompt_draw()
794	prompt[2] = s
795
796	def prompt_set_cursor_column(c):
797	prompt[3] = c
798
799	def prompt_insert(char):
800	schedule_prompt_draw()
801	c = prompt_cursor()
802	prompt_chars().insert(c, char)
803	prompt_set_cursor(c + 1)
804
805	@command('prompt-delete')
806	def prompt_delete():
807	schedule_prompt_draw()
808	c = prompt_cursor()
809	chars = prompt_chars()
810	if c < len(chars):
811	chars.pop(c)
812
813	@command('prompt-backspace')
814	def prompt_backspace():
815	schedule_prompt_draw()
816	c = prompt_cursor()
817	if prompt_set_cursor(c - 1):
818	prompt_delete()
819
820	@command('prompt-submit')
821	def prompt_submit():
822	schedule_prompt_draw()
823	line = ''.join(prompt_chars())
824	prompt_clear()
825	if len(line) == 0:
826	return
827	try:
828	if line.startswith('/'):
829	line = line[1:]
830	if not line:
831	raise CommandError('empty command')
832	if not line.startswith('/'):
833	run_command(line)
834	return
835	buf_privmsg(cur_buf, line)
836	except CommandError, e:
837	error(e, cur_buf)
838
839	command('prompt-forward')(lambda: prompt_set_cursor(prompt_cursor() + 1))
840	command('prompt-backward')(lambda: prompt_set_cursor(prompt_cursor() - 1))
841	command('prompt-start')(lambda: prompt_set_cursor(0))
842	command('prompt-end')(lambda: prompt_set_cursor(len(prompt_chars())))
843
844	def prompt_draw():
845	if scr_height < 1:
846	return
847	write_out(t.cursor_pos(scr_height, 1))
848	if scr_width < 4:
849	write_out(t.ERASE_LINE_TO_END)
850	return
851	prompt_str = '> '
852	write_out(prompt_str)
853	chars = prompt_chars()
854	cursor = prompt_cursor()
855	hscr = prompt_hscroll()
856	before_cursor = asciify(chars[:cursor])
857	cursor_offset = len(before_cursor) - hscr
858	max_width = scr_width - len(prompt_str)
859	if not 0 <= cursor_offset < max_width:
860	hscr = max(0, hscr + cursor_offset - max_width/2)
861	prompt_set_hscroll(hscr)
862	cursor_offset = len(before_cursor) - hscr
863	prompt_set_cursor_column(1 + len(prompt_str) + cursor_offset)
864	printable = (before_cursor[hscr:] +
865	asciify(chars[cursor:])[:max_width - cursor_offset])
866	write_out(printable)
867	write_out(t.ERASE_LINE_TO_END)
868	schedule_refresh()
869	prompt_draw_done()
870
871	def conn_ping_status(c):
872	t0 = conn_ping_ts(c)
873	t1 = conn_pong_ts(c)
874	if t1 < t0:
875	if not ping_draw_flag():
876	set_ping_draw()
877	run_in(5, sequence(clr_ping_draw, status_draw))
878	delta = int(mono_time() - t0)
879	return '%d...' % (delta - delta%5)
880	return '%.3f' % (t1 - t0)
881
882	def status_draw():
883	row = scr_height - 1
884	if row < 1:
885	return
886	if kbd_state is ks_esc:
887	status = 'ESC-'
888	elif kbd_state is ks_cx:
889	status = 'C-x-'
890	elif kbd_state in (ks_cseq, ks_cs_intermed):
891	status = ' '.join(['CSI'] + list(str(kbd_accum[len(CSI):]))) + '-'
892	elif cur_buf is buffers[0]:
893	status = ''
894	else:
895	parent = buf_parent(cur_buf)
896	network = buf_name(cur_buf if parent is None else parent)
897	status = asciify(network)
898	c = network_conns.get(network)
899	if c:
900	status = asciify(conn_nick(c) + '@') + status
901	if parent:
902	venue = buf_name(cur_buf)
903	status += ' \| ' + asciify(venue)
904	if c and conn_sock(c):
905	if not conn_registered(c):
906	status += ' \| unregistered'
907	elif parent and is_chan(venue) and venue not in conn_channels(c):
908	status += ' \| unjoined'
909	status += ' \| ping: %s' % conn_ping_status(c)
910	else:
911	status += ' \| offline'
912	write_out(t.cursor_pos(row, 1))
913	write_out(t.ATTR_REVERSE)
914	write_out(pad_or_clip_str(status, scr_width))
915	write_out(t.ATTR_NONE)
916	schedule_refresh()
917	status_draw_done()
918
919	# buflist singleton: lists the open buffers in a left-hand pane
920
921	buflist = [0, BUFLIST_WIDTH_START, cur_buf, cur_buf, cur_buf]
922	buflist_vscroll = lambda: buflist[0]
923	buflist_width = lambda: buflist[1]
924	buflist_cursor = lambda: buflist[2]
925	buflist_last = lambda: buflist[3]
926
927	def buflist_set_width(w):
928	schedule_redraw()
929	if w > scr_width:
930	w = scr_width - (scr_width - w) % BUFLIST_WIDTH_STEP
931	buflist[1] = max(BUFLIST_WIDTH_MIN, w)
932
933	def buflist_set_cursor(b):
934	schedule_buflist_draw()
935	buflist[2] = b
936
937	def buflist_set_last(b):
938	buflist[3] = b
939
940	def buflist_select(b):
941	global cur_buf
942	schedule_buflist_draw()
943	schedule_buf_draw()
944	schedule_status_draw()
945	if b is not cur_buf:
946	buflist_set_last(cur_buf)
947	# don't autoscroll a newly selected window (at_end will get restored on
948	# draw if it's still at the end)
949	buf_clr_at_end(b)
950	buflist_set_cursor(b)
951	cur_buf = b
952
953	command('buflist-switch-next')(
954	lambda: buflist_select(
955	get_clipped(buffers, find_buf(cur_buf) + 1)))
956	command('buflist-switch-prev')(
957	lambda: buflist_select(
958	get_clipped(buffers, find_buf(cur_buf) - 1)))
959	command('buflist-last-selected')(lambda: buflist_select(buflist_last()))
960
961	command('buflist-next')(
962	lambda: buflist_set_cursor(
963	get_clipped(buffers, find_buf(buflist_cursor()) + 1)))
964	command('buflist-prev')(
965	lambda: buflist_set_cursor(
966	get_clipped(buffers, find_buf(buflist_cursor()) - 1)))
967	command('buflist-top')(lambda: buflist_set_cursor(buffers[0]))
968	command('buflist-bottom')(lambda: buflist_set_cursor(buffers[-1]))
969	command('buflist-shrink')(lambda:
970	buflist_set_width(buflist_width() - BUFLIST_WIDTH_STEP))
971	command('buflist-grow')(lambda:
972	buflist_set_width(buflist_width() + BUFLIST_WIDTH_STEP))
973
974	@command('buflist-submit')
975	def buflist_submit():
976	buflist_exit()
977	buflist_select(buflist_cursor())
978
979	def buflist_draw():
980	schedule_refresh()
981	top_row = 2
982	h = scr_height - 3
983	w = min(scr_width, buflist_width() - 1)
984	cursor = buflist_cursor()
985	def network_status(network):
986	c = network_conns.get(network)
987	if c is None: # not connected
988	return ' '
989	sock = conn_sock(c)
990	if sock is None: # down, awaiting reconnection
991	return '~'
992	fd = conn_sock(c).fileno()
993	if fd in opening_conns: # DNS / TCP handshake
994	return '~'
995	if conn_registered(c):
996	return '='
997	else: # TCP connected but unregistered (no WELCOME yet)
998	return '-'
999	def get_label(buf):
1000	parts = []
1001	if buf is cur_buf:
1002	parts.append('*')
1003	elif buf is buflist_last():
1004	parts.append('-')
1005	else:
1006	parts.append(' ')
1007	if buf_parent(buf) is None:
1008	if buf is buffers[0]:
1009	parts.append(' ')
1010	else:
1011	parts.append(network_status(buf_name(buf)))
1012	else: # channel/pm
1013	parts.append(' ')
1014	parts.append(asciify(buf_name(buf)))
1015	unread = buf_unread(buf)
1016	if unread > 0:
1017	parts.append(' +%d' % unread)
1018	label = ''.join(parts)
1019	if buf is cursor and buflist_flag():
1020	return t.render((t.A_REVERSE, pad_or_clip_str(label, w)))
1021	else:
1022	return clip_str(label, w)
1023	write_out(t.cursor_pos(2, 1))
1024	scroll = buflist_vscroll()
1025	for row in range(h):
1026	write_out(t.cursor_pos(top_row + row, w) + t.ERASE_LINE_FROM_START)
1027	i = scroll + row
1028	if i < len(buffers):
1029	write_out(CR + get_label(buffers[i]))
1030	buflist_draw_done()
1031
1032	def buflist_vline_draw():
1033	top_row = 2
1034	height = scr_height - 3
1035	column = buflist_width()
1036	if column > scr_width:
1037	return
1038	move_down = LF if column == scr_width else BS + LF
1039	write_out(t.cursor_pos(top_row, column))
1040	write_out(SO)
1041	write_out(move_down.join(t.SGC_VBAR*height))
1042	write_out(SI)
1043
1044	command('prompt-enter')(sequence(schedule_refresh, prompt_enter))
1045	command('prompt-exit')(sequence(schedule_refresh, prompt_exit))
1046	command('buflist-enter')(sequence(schedule_buflist_draw, buflist_enter))
1047	command('redraw')(schedule_redraw)
1048
1049	# Terminal input state machine
1050
1051	# Only valid control sequences per ECMA-48 5ed. sec. 5.4 are accepted.
1052	# Esc always cancels any sequence in progress and moves to ks_esc, to avoid
1053	# control sequences leaking through as text input. C-g always cancels and
1054	# returns to ks_start.
1055
1056	kbd_accum = bytearray()
1057	kaccum = kbd_accum.extend
1058
1059	def kaccept(sym=''):
1060	kaccum(sym)
1061	seq = str(kbd_accum)
1062	ktrans(ks_start)
1063	def try_keymap(km):
1064	cmd = km.get(seq)
1065	if cmd is None:
1066	return False
1067	run_command(cmd)
1068	return True
1069	try:
1070	if try_keymap(GLOBAL_KEYS):
1071	return
1072	elif buflist_flag():
1073	try_keymap(BUFLIST_KEYS)
1074	elif prompt_flag():
1075	if not try_keymap(PROMPT_KEYS):
1076	if len(seq) == 1 and not is_ctrl(seq):
1077	prompt_insert(seq)
1078	else:
1079	try_keymap(BUF_KEYS)
1080	except CommandError, e:
1081	error(e, cur_buf)
1082
1083	def ktrans(state):
1084	global kbd_state
1085	kbd_state = state
1086	schedule_status_draw()
1087	if state in (ks_start, ks_esc):
1088	del kbd_accum[:]
1089	elif state is ks_cseq:
1090	del kbd_accum[:]
1091	kaccum(CSI)
1092
1093	# States
1094
1095	def ks_start(sym):
1096	if sym == C_X:
1097	kaccum(C_X)
1098	ktrans(ks_cx)
1099	elif sym == ESC:
1100	ktrans(ks_esc)
1101	else:
1102	kaccept(sym)
1103
1104	def ks_cx(sym):
1105	if sym == C_G:
1106	ktrans(ks_start)
1107	elif sym == ESC:
1108	ktrans(ks_esc)
1109	else:
1110	kaccept(casemap_ascii(ctrl(sym)) if is_ctrl(sym) else sym)
1111
1112	def ks_esc(sym):
1113	if sym == C_G:
1114	ktrans(ks_start)
1115	elif sym == ESC:
1116	pass
1117	elif sym == '[':
1118	ktrans(ks_cseq)
1119	else:
1120	kaccept(meta(sym))
1121
1122	def ks_cseq(sym):
1123	if sym == ESC:
1124	ktrans(ks_esc)
1125	elif '\x20' <= sym <= '\x2F':
1126	kaccum(sym)
1127	ktrans(ks_cs_intermed)
1128	elif '\x30' <= sym <= '\x3F':
1129	kaccum(sym)
1130	schedule_status_draw()
1131	elif '\x40' <= sym <= '\x7E':
1132	kaccept(sym)
1133	else:
1134	ktrans(ks_start)
1135
1136	def ks_cs_intermed(sym):
1137	if sym == ESC:
1138	ktrans(ks_esc)
1139	elif '\x20' <= sym <= '\x2F':
1140	kaccum(sym)
1141	schedule_status_draw()
1142	elif '\x40' <= sym <= '\x7E':
1143	kaccept(sym)
1144	else:
1145	ktrans(ks_start)
1146
1147	kbd_state = ks_start
1148
1149	def buf_conn(buf):
1150	if buf is buffers[0]:
1151	raise CommandError('this window not associated with a network')
1152	parent = buf_parent(buf)
1153	network = buf_name(buf if parent is None else parent)
1154	try:
1155	return network_conns[network]
1156	except KeyError:
1157	raise CommandError('not connected to %s' % network)
1158
1159	def buf_registered_conn(buf):
1160	c = buf_conn(buf)
1161	if conn_sock(c) is None:
1162	raise CommandError('connection to %s is down' % conn_network(c))
1163	if not conn_registered(c):
1164	raise CommandError('connection to %s not registered' % conn_network(c))
1165	return c
1166
1167	@command('connect', 1, 4)
1168	def connect_cmd(*args):
1169	net = args[0]
1170	if net in network_conns:
1171	raise CommandError('connect: connection already active for %s' % net)
1172
1173	if not safe_filename(net):
1174	raise CommandError('connect: bad network name: %s' % net)
1175	conf_paths = (('nets', net), ())
1176
1177	if len(args) > 1:
1178	addrs = [args[1]]
1179	else:
1180	addrs = config_lines(get_config('addrs', conf_paths))
1181	if addrs is None:
1182	raise CommandError('connect: no addrs for network %s' % net)
1183	try:
1184	addrs = map(parse_address, addrs)
1185	except ValueError, e:
1186	raise CommandError('connect: %s' % e)
1187
1188	if len(args) > 2:
1189	nick = args[2]
1190	else:
1191	nick = get_config('nick', conf_paths)
1192	if nick is None:
1193	raise CommandError('connect: no nick for %s' % net)
1194	if not valid_nick(nick):
1195	raise CommandError('connect: bad nick: %s' % nick)
1196
1197	if len(args) > 3:
1198	pw = args[3]
1199	else:
1200	pw = get_config('pass', conf_paths)
1201	if not valid_password(pw):
1202	raise CommandError(
1203	'connect: illegal character in password for %s' % net)
1204
1205	conn_start(new_conn(net, addrs, nick, pw))
1206
1207	@command('disconnect', 0, 1)
1208	def disconnect_cmd(net=None):
1209	if net is None:
1210	c = buf_conn(cur_buf)
1211	net = conn_network(c)
1212	else:
1213	try:
1214	c = network_conns[net]
1215	except KeyError:
1216	raise CommandError('no connection for network %s' % net)
1217	del network_conns[net]
1218	conn_info(c, 'disconnected')
1219	conn_close(c)
1220
1221	@command('join', 1, 2)
1222	def join_cmd(chan, key=None):
1223	if not valid_chan(chan):
1224	raise CommandError('join: bad channel name: %s' % chan)
1225	conn_join(buf_registered_conn(cur_buf), chan, key)
1226
1227	@command('kick', 1, extended_arg=True)
1228	def kick_cmd(user, msg=''):
1229	chan = buf_name(cur_buf)
1230	if buf_parent(cur_buf) is None or not is_chan(chan):
1231	raise CommandError('kick: this window not a channel')
1232	conn_send(buf_registered_conn(cur_buf), 'KICK', [chan, user, msg])
1233
1234	@command('list', 0, 1)
1235	def list_cmd(*args):
1236	conn_send(buf_registered_conn(cur_buf), 'LIST', args)
1237
1238	@command('me', extended_arg=True)
1239	def me_cmd(msg=''):
1240	buf_privmsg(cur_buf, '\x01ACTION %s\x01' % msg)
1241
1242	@command('mode', 1, 3)
1243	def mode_cmd(*args):
1244	conn_send(buf_registered_conn(cur_buf), 'MODE', args)
1245
1246	@command('msg', 1, extended_arg=True)
1247	def msg_cmd(target, msg=None):
1248	c = buf_registered_conn(cur_buf)
1249	if is_chan(target) and not valid_chan(target):
1250	raise CommandError('msg: bad channel name: %s' % target)
1251	if msg:
1252	conn_privmsg(c, target, msg)
1253	buflist_select(get_buf(target, conn_network(c)))
1254
1255	@command('names', 0, 1)
1256	def names_cmd(*args):
1257	conn_send(buf_registered_conn(cur_buf), 'NAMES', args)
1258
1259	@command('nick', 1)
1260	def nick_cmd(nick):
1261	c = buf_conn(cur_buf)
1262	if conn_sock(c) is None:
1263	schedule_status_draw()
1264	conn_set_nick(c, nick)
1265	conn_info(c, 'nick changed to %s for next reconnection' % nick)
1266	else:
1267	if not conn_registered(c):
1268	schedule_status_draw()
1269	conn_set_nick(c, nick)
1270	conn_info(c, 'nick changed to %s' % nick)
1271	conn_set_ping_ts(c, mono_time())
1272	conn_run_in(c, PING_TIMEOUT, conn_reg_timeout)
1273	conn_send(c, 'NICK', [nick])
1274
1275	@command('part', extended_arg=True)
1276	def part_cmd(msg=''):
1277	chan = buf_name(cur_buf)
1278	if buf_parent(cur_buf) is None or not is_chan(chan):
1279	raise CommandError('part: this window not a channel')
1280	conn_send(buf_registered_conn(cur_buf), 'PART', [chan, msg])
1281
1282	@command('quit', extended_arg=True)
1283	def quit_cmd(*msg):
1284	schedule_quit()
1285	for c in open_conns.itervalues():
1286	conn_send(c, 'QUIT', msg)
1287
1288	@command('send', extended_arg=True)
1289	def send_cmd(line):
1290	if len(line) > MAX_MSG_LEN:
1291	raise CommandError('send: line too long')
1292	conn_write(buf_registered_conn(cur_buf), line)
1293
1294	@command('topic', 0, 1)
1295	def topic_cmd(chan=None):
1296	if chan is None:
1297	chan = buf_name(cur_buf)
1298	if buf_parent(cur_buf) is None or not is_chan(chan):
1299	raise CommandError(
1300	'topic: this window not a channel and none specified')
1301	conn_send(buf_registered_conn(cur_buf), 'TOPIC', [chan])
1302
1303	@command('set-topic', extended_arg=True)
1304	def set_topic_cmd(topic=''):
1305	chan = buf_name(cur_buf)
1306	if buf_parent(cur_buf) is None or not is_chan(chan):
1307	raise CommandError('set-topic: this window not a channel')
1308	conn_send(buf_registered_conn(cur_buf), 'TOPIC', [chan, topic])
1309
1310	@command('whois', 1)
1311	def whois_cmd(nick):
1312	conn_send(buf_registered_conn(cur_buf), 'WHOIS', [nick])
1313
1314	@command('whowas', 1)
1315	def whowas_cmd(nick):
1316	conn_send(buf_registered_conn(cur_buf), 'WHOWAS', [nick])
1317
1318	@command('close')
1319	def close_cmd():
1320	parent = buf_parent(cur_buf)
1321	if parent is None:
1322	raise CommandError(
1323	"close: won't close a top-level window (try close-net)")
1324	venue = buf_name(cur_buf)
1325	try:
1326	c = buf_registered_conn(cur_buf)
1327	except CommandError:
1328	pass
1329	else:
1330	if venue in conn_channels(c):
1331	conn_send(c, 'PART', [venue, ''])
1332	del conn_channels(c)[venue]
1333	close_buf(cur_buf)
1334
1335	@command('close-net')
1336	def close_net_cmd():
1337	raise CommandError('stub') # TODO
1338
1339	def place_cursor():
1340	if buflist_flag():
1341	write_out(t.cursor_pos(max(1, scr_height - 2),
1342	clip(1, scr_width, buflist_width() - 1)))
1343	elif prompt_flag():
1344	write_out(t.cursor_pos(scr_height, prompt_cursor_column()))
1345	else:
1346	write_out(t.cursor_pos(max(1, scr_height - 2), max(1, scr_width)))
1347
1348	def refresh_if_needed():
1349	if redraw_flag():
1350	write_out(t.ERASE_FULL)
1351	buf_draw(cur_buf)
1352	buflist_vline_draw()
1353	buflist_draw()
1354	status_draw()
1355	prompt_draw()
1356	redraw_done()
1357	else:
1358	if buf_draw_flag():
1359	buf_draw(cur_buf)
1360	if buflist_draw_flag():
1361	buflist_draw()
1362	if status_draw_flag():
1363	status_draw()
1364	if prompt_draw_flag():
1365	prompt_draw()
1366	if refresh_flag():
1367	place_cursor()
1368	flush_out()
1369	refresh_done()
1370
1371	#
1372	# IRC stuff
1373	#
1374
1375	RPL_WELCOME = 1
1376	RPL_NOTOPIC = 331
1377	RPL_TOPIC = 332
1378	RPL_NAMREPLY = 353
1379	RPL_ENDOFNAMES = 366
1380	ERR_NICKNAMEINUSE = 433
1381	ERR_NICKCOLLISION = 436
1382	ERR_NOTREGISTERED = 451
1383
1384	MAX_MSG_LEN = 510
1385	MAX_CHAN_LEN = 50
1386	MAX_NICK_LEN = 31
1387
1388	IRC_ILLEGAL = NUL + CR + LF
1389	CHAN_ILLEGAL = IRC_ILLEGAL + BEL + ' ,:'
1390	CHAN_START = '&#+!'
1391	IRC_SPECIAL = '[]\\`_^{\|}'
1392
1393	LETTER = char_range('AZ') + char_range('az')
1394	DIGIT = char_range('09')
1395	NICK_START = LETTER + IRC_SPECIAL
1396	NICK_BODY = NICK_START + DIGIT + '-'
1397
1398	class ProtocolError(Exception):
1399	pass
1400
1401	def build_msg(prefix, cmd, params):
1402	"""Build an IRC wire message.
1403
1404	Conditions caller must enforce:
1405	* No args may contain NUL, CR, or LF
1406	* Only last param may be empty, contain spaces, or start with :
1407	* Valid cmd
1408	* 15 parameters max
1409	"""
1410	parts = []
1411	if prefix is not None:
1412	parts.append(':' + prefix)
1413	parts.append(cmd)
1414	if len(params):
1415	parts.extend(params[:-1])
1416	parts.append(':' + params[-1])
1417	return ' '.join(parts)
1418
1419	def max_param_len(cmd, prefix=None):
1420	# colon before prefix + space after prefix
1421	prefix_len = 0 if prefix is None else len(prefix) + 2
1422	# space after cmd + colon before last param
1423	return MAX_MSG_LEN - prefix_len - len(cmd) - 2
1424
1425	def parse_msg(msg):
1426	if any(c in msg for c in IRC_ILLEGAL):
1427	raise ProtocolError('illegal character in message')
1428	start = 0
1429	end = len(msg)
1430	def next_word():
1431	cut = msg.find(' ', start)
1432	if cut == -1:
1433	cut = end
1434	return cut + 1, msg[start:cut]
1435	if msg.startswith(':'):
1436	start = 1
1437	start, prefix = next_word()
1438	else:
1439	prefix = None
1440	start, cmd = next_word()
1441	if not cmd:
1442	raise ProtocolError('message with no command')
1443	params = []
1444	while start < end:
1445	if msg[start] == ':':
1446	params.append(msg[start+1:])
1447	break
1448	start, param = next_word()
1449	params.append(param)
1450	return prefix, casemap_ascii(cmd), params
1451
1452	is_chan = lambda n: len(n) > 0 and n[0] in CHAN_START
1453
1454	def valid_chan(n):
1455	return is_chan(n) and len(n) <= MAX_CHAN_LEN \
1456	and not any(c in CHAN_ILLEGAL for c in n)
1457
1458	def valid_nick(n):
1459	return 0 < len(n) <= MAX_NICK_LEN \
1460	and n[0] in NICK_START \
1461	and all(c in NICK_BODY for c in n[1:])
1462
1463	def valid_password(p):
1464	return p is None or (
1465	len(p) <= max_param_len('PASS')
1466	and not any(c in IRC_ILLEGAL for c in p))
1467
1468	sender_nick = lambda s: s.split('!', 1)[0]
1469
1470	#
1471	# Networking / main loop
1472	#
1473
1474	set_nonblock = lambda fd: fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) \| O_NONBLOCK)
1475
1476	def read_all(fd):
1477	chunks = []
1478	try:
1479	chunk = read(fd, 4096)
1480	if not chunk:
1481	raise EOFError
1482	while chunk:
1483	chunks.append(chunk)
1484	chunk = read(fd, 4096)
1485	except EnvironmentError, e:
1486	if e.errno not in (EAGAIN, EWOULDBLOCK):
1487	raise
1488	return ''.join(chunks)
1489
1490	def new_conn(network, addrs, nick, password=None):
1491	i = rand_int(len(addrs))
1492	addrs = addrs[i:] + addrs[:i]
1493	return [network, None, '', '', addrs, nick, password, False, dict(),
1494	IRC_CASEMAP['rfc1459'], RECONN_DELAY_MIN, 0, 0, 0]
1495
1496	conn_network = lambda c: c[0]
1497	conn_sock = lambda c: c[1]
1498	conn_rdbuf = lambda c: c[2]
1499	conn_wrbuf = lambda c: c[3]
1500	conn_addrs = lambda c: c[4]
1501	conn_nick = lambda c: c[5]
1502	conn_password = lambda c: c[6]
1503	conn_registered = lambda c: c[7]
1504	conn_channels = lambda c: c[8]
1505	conn_casemap = lambda c, s: c[9](s)
1506	conn_count = lambda c: c[11]
1507	conn_ping_ts = lambda c: c[12]
1508	conn_pong_ts = lambda c: c[13]
1509
1510	conn_set_sock = lambda c, s: c.__setitem__(1, s)
1511	conn_rdbuf_add = lambda c, b: c.__setitem__(2, c[2] + b)
1512	conn_rdbuf_rm = lambda c, n: c.__setitem__(2, c[2][n:])
1513	conn_wrbuf_add = lambda c, b: c.__setitem__(3, c[3] + b)
1514	conn_wrbuf_rm = lambda c, n: c.__setitem__(3, c[3][n:])
1515	conn_set_nick = lambda c, n: c.__setitem__(5, n)
1516	conn_set_registered = lambda c: c.__setitem__(7, True)
1517	conn_clr_registered = lambda c: c.__setitem__(7, False)
1518	conn_reset_reconn_delay = lambda c: c.__setitem__(10, RECONN_DELAY_MIN)
1519	conn_set_count = lambda c, n: c.__setitem__(11, n)
1520	conn_set_ping_ts = lambda c, t: c.__setitem__(12, t)
1521	conn_set_pong_ts = lambda c, t: c.__setitem__(13, t)
1522
1523	def conn_reconn_delay(c):
1524	# limited exponential backoff
1525	d = c[10]
1526	c[10] = min(2*d, RECONN_DELAY_MAX)
1527	return d
1528
1529	conn_nick_lc = lambda c: conn_casemap(c, conn_nick(c))
1530
1531	def conn_run_in(c, delay, method, run_if_down=False):
1532	count = conn_count(c)
1533	def run():
1534	# Drop leftover tasks from old connections
1535	if c is network_conns.get(conn_network(c)) and conn_count(c) == count \
1536	and (run_if_down or conn_sock(c) is not None):
1537	method(c)
1538	run_in(delay, run)
1539
1540	def conn_log_msg(c, venue, m):
1541	network = conn_network(c)
1542	if venue is None:
1543	buf = get_buf(network, None)
1544	else:
1545	buf = get_buf(venue, network)
1546	buf_log_msg(buf, m)
1547	file_log_msg(network, venue, m)
1548
1549	def conn_info(c, msg):
1550	conn_log_msg(c, None, m_client(msg))
1551
1552	def conn_error(c, msg):
1553	conn_log_msg(c, None, m_client('ERROR: ' + msg))
1554
1555	opening_conns = {}
1556	network_conns = {}
1557	def conn_start(c):
1558	schedule_buflist_draw()
1559	schedule_status_draw()
1560	net = conn_network(c)
1561	assert conn_sock(c) is None, 'socket exists when starting connection'
1562	sock = socket()
1563	set_nonblock(sock.fileno())
1564	conn_set_sock(c, sock)
1565	conn_set_count(c, conn_count(c) + 1)
1566	addrs = conn_addrs(c)
1567	addrs.append(addrs.pop(0))
1568	conn_info(c, 'connecting to %s' % format_address(addrs[0]))
1569	network_conns[net] = opening_conns[sock.fileno()] = c
1570	try:
1571	sock.connect(addrs[0]) # TODO async DNS
1572	except SockError, e:
1573	if e.errno != EINPROGRESS:
1574	del opening_conns[sock.fileno()]
1575	conn_error(c, e.strerror)
1576	else:
1577	conn_handle_connected(c)
1578
1579	def conn_write(c, msg):
1580	if len(msg) > MAX_MSG_LEN:
1581	msg = msg[:MAX_MSG_LEN]
1582	conn_error(c, 'outbound message truncated')
1583	conn_wrbuf_add(c, msg + CRLF)
1584
1585	def conn_send(c, cmd, params, prefix=None):
1586	conn_write(c, build_msg(prefix, cmd, params))
1587
1588	open_conns = {}
1589	def conn_handle_connected(c):
1590	n = conn_nick(c)
1591	p = conn_password(c)
1592	s = conn_sock(c)
1593	e = s.getsockopt(SOL_SOCKET, SO_ERROR)
1594	if e == EINPROGRESS:
1595	return
1596	schedule_buflist_draw()
1597	schedule_status_draw()
1598	del opening_conns[s.fileno()]
1599	if e != 0:
1600	conn_error(c, strerror(e))
1601	conn_close(c)
1602	return
1603	conn_reset_reconn_delay(c)
1604	open_conns[s.fileno()] = c
1605	conn_info(c, 'connection established')
1606	conn_set_ping_ts(c, mono_time())
1607	conn_run_in(c, PING_TIMEOUT, conn_reg_timeout)
1608	if p is not None:
1609	conn_send(c, 'PASS', [p])
1610	conn_send(c, 'NICK', [n])
1611	conn_send(c, 'USER', [n, '0', '*', n])
1612
1613	def conn_close(c):
1614	sock = conn_sock(c)
1615	if sock is None:
1616	return
1617	schedule_buflist_draw()
1618	schedule_status_draw()
1619	fd = sock.fileno()
1620	if fd in open_conns:
1621	del open_conns[fd]
1622	elif fd in opening_conns:
1623	del opening_conns[fd]
1624	try:
1625	sock.shutdown(SHUT_RDWR)
1626	except SockError:
1627	pass
1628	sock.close()
1629	conn_set_sock(c, None)
1630	conn_rdbuf_rm(c, len(conn_rdbuf(c)))
1631	conn_wrbuf_rm(c, len(conn_wrbuf(c)))
1632	conn_clr_registered(c)
1633	conn_info(c, 'connection closed')
1634	if conn_network(c) in network_conns:
1635	delay = conn_reconn_delay(c)
1636	conn_run_in(c, delay, conn_start, True)
1637	conn_info(c, 'reconnecting in %d seconds' % delay)
1638
1639	def conn_handle_data(c, data):
1640	conn_rdbuf_add(c, data)
1641	data = conn_rdbuf(c)
1642	start = 0
1643	while start < len(data):
1644	end = data.find(CRLF, start)
1645	if end == -1:
1646	if len(data) - start >= MAX_MSG_LEN:
1647	conn_error(c, 'received oversize message')
1648	conn_close(c)
1649	return
1650	break
1651	if end > start:
1652	try:
1653	conn_handle_msg(c, data[start:end])
1654	except ProtocolError, e:
1655	conn_error(c, e)
1656	start = end + 2
1657	conn_rdbuf_rm(c, start)
1658
1659	def conn_handle_msg(c, msg):
1660	#pylint: disable=unbalanced-tuple-unpacking,too-many-locals
1661	prefix, cmd, params = parse_msg(msg)
1662
1663	def welcome():
1664	if destination != conn_nick(c): # for pre-welcome nick change
1665	schedule_status_draw()
1666	conn_info(c, 'nick changed to %s' % destination)
1667	conn_set_nick(c, destination)
1668	conn_log_msg(c, None, m_server(prefix or '', ' '.join(params)))
1669	if not conn_registered(c):
1670	schedule_buflist_draw()
1671	conn_set_registered(c)
1672	pong()
1673	for chan in conn_channels(c):
1674	conn_join(c, chan)
1675	conn_channels(c).clear()
1676
1677	def names_reply():
1678	if len(params) != 3:
1679	conn_error(c, 'RPL_NAMREPLY with bad parameter count: %s' % msg)
1680	return
1681	_, chan, names = params
1682	chan_lc = conn_casemap(c, chan)
1683	members = conn_channels(c).get(chan_lc)
1684	conn_log_msg(c, None if members is None else chan_lc,
1685	m_names(prefix or '', chan, names))
1686	if members is not None:
1687	for nick in names.split(' '):
1688	if not nick:
1689	conn_error(c, 'RPL_NAMREPLY with empty nick')
1690	break
1691	if nick[0] in '@+':
1692	nick = nick[1:]
1693	members.add(conn_casemap(c, nick))
1694
1695	def end_names():
1696	if len(params) != 2:
1697	conn_error(c, 'RPL_ENDOFNAMES with bad parameter count: %s' % msg)
1698	return
1699	chan = params[0]
1700	chan_lc = conn_casemap(c, chan)
1701	conn_log_msg(c, chan_lc if chan_lc in conn_channels(c) else None,
1702	m_endnames(prefix or '', chan))
1703
1704	def error_msg():
1705	if len(params) != 1:
1706	conn_error(c, 'ERROR with bad parameter count: %s' % msg)
1707	return
1708	conn_log_msg(c, None, m_error(prefix or '', params[0]))
1709
1710	def ping():
1711	conn_send(c, 'PONG', params)
1712
1713	def pong():
1714	schedule_status_draw()
1715	conn_set_pong_ts(c, mono_time())
1716	conn_run_in(c, PING_INTERVAL, conn_ping)
1717
1718	def privmsg():
1719	if len(params) != 2:
1720	conn_error(c, 'message with bad parameter count: %s' % msg)
1721	return
1722	target, content = params
1723	target_lc = conn_casemap(c, target)
1724	if prefix is None:
1725	conn_error(c, 'message without sender: %s' % msg)
1726	return
1727	sender = sender_nick(prefix)
1728	if target_lc == conn_nick_lc(c): # PM
1729	venue = conn_casemap(c, sender)
1730	elif valid_chan(target_lc):
1731	if target_lc in conn_channels(c):
1732	venue = target_lc
1733	else:
1734	return # drop messages to unknown channels
1735	elif target_lc == '*': # not sure if standard but freenode does this
1736	venue = None
1737	else:
1738	conn_error(c, 'message to unknown target: %s' % msg)
1739	return
1740	conn_log_msg(c, venue,
1741	(m_notice if cmd == 'notice' else m_privmsg)(sender, content))
1742
1743	def join():
1744	if len(params) != 1:
1745	conn_error(c, 'JOIN with bad parameter count: %s' % msg)
1746	return
1747	chan, = params
1748	chan_lc = conn_casemap(c, chan)
1749	if prefix is None:
1750	conn_error(c, 'JOIN without sender: %s' % msg)
1751	return
1752	sender_lc = conn_casemap(c, sender_nick(prefix))
1753	channels_dict = conn_channels(c)
1754	if sender_lc == conn_nick_lc(c):
1755	if chan_lc in channels_dict:
1756	conn_error(c, 'JOIN to already joined channel %s' % chan)
1757	return
1758	channels_dict[chan_lc] = set()
1759	else:
1760	if chan_lc not in channels_dict:
1761	conn_error(c, 'JOIN %s to unknown channel %s' % (prefix, chan))
1762	return
1763	channels_dict[chan_lc].add(sender_lc)
1764	conn_log_msg(c, chan_lc, m_join(prefix, chan))
1765
1766	def mode():
1767	if len(params) < 1:
1768	conn_error(c, 'MODE with bad parameter count: %s' % msg)
1769	return
1770	target = params[0]
1771	modes = ' '.join(params[1:])
1772	target_lc = conn_casemap(c, target)
1773	if prefix is None:
1774	conn_error(c, 'MODE without sender: %s' % msg)
1775	return
1776	if is_chan(target_lc):
1777	if target_lc not in conn_channels(c):
1778	conn_error(c, 'MODE to unknown channel: %s' % msg)
1779	return
1780	conn_log_msg(c, target_lc, m_chanmode(prefix, target, modes))
1781	else:
1782	if not target_lc == prefix == conn_nick(c):
1783	conn_error(c, 'MODE to unknown target: %s' % msg)
1784	return
1785	conn_log_msg(c, None, m_mode(prefix, modes))
1786
1787	def part():
1788	if len(params) == 1:
1789	comment = ''
1790	elif len(params) == 2:
1791	comment = params[1]
1792	else:
1793	conn_error(c, 'PART with bad parameter count: %s' % msg)
1794	return
1795	parted_chans = params[0].split(',')
1796	if prefix is None:
1797	conn_error(c, 'PART without sender: %s' % msg)
1798	return
1799	sender_lc = conn_casemap(c, sender_nick(prefix))
1800	channels_dict = conn_channels(c)
1801	me = (sender_lc == conn_nick_lc(c))
1802	for chan in parted_chans:
1803	chan_lc = conn_casemap(c, chan)
1804	if chan_lc not in channels_dict:
1805	# drop PARTs from unknown channels (e.g. closed window)
1806	continue
1807	try:
1808	if me:
1809	del channels_dict[chan_lc]
1810	conn_info(c, 'parted %s' % chan)
1811	schedule_status_draw()
1812	else:
1813	channels_dict[chan_lc].remove(sender_lc)
1814	except KeyError:
1815	conn_error(c, 'PART non-member %s from %s' % (prefix, chan))
1816	continue
1817	conn_log_msg(c, chan_lc, m_part(prefix, chan, comment))
1818
1819	def quit_msg():
1820	if len(params) != 1:
1821	conn_error(c, 'QUIT with bad parameter count: %s' % msg)
1822	return
1823	quit_msg, = params
1824	if prefix is None:
1825	conn_error(c, 'QUIT without sender [%s]' % quit_msg)
1826	return
1827	sender_lc = conn_casemap(c, sender_nick(prefix))
1828	for chan_lc, members in conn_channels(c).items():
1829	if sender_lc in members:
1830	conn_log_msg(c, chan_lc, m_quit(prefix, quit_msg))
1831	members.remove(sender_lc)
1832
1833	def kick():
1834	if len(params) < 2 or len(params) > 3:
1835	conn_error(c, 'KICK with bad parameter count: %s' % msg)
1836	return
1837	if prefix is None:
1838	conn_error(c, 'KICK without sender: %s' % msg)
1839	return
1840	chan = params[0]
1841	chan_lc = conn_casemap(c, chan)
1842	kicked_user = params[1]
1843	kicked_user_lc = conn_casemap(c, kicked_user)
1844	comment = params[2] if len(params) == 3 else ''
1845	channels_dict = conn_channels(c)
1846	if kicked_user_lc == conn_nick_lc(c):
1847	try:
1848	del channels_dict[chan_lc]
1849	except KeyError:
1850	conn_error(c, 'KICK from unknown channel %s by %s [%s]'
1851	% (chan, prefix, comment))
1852	return
1853	schedule_status_draw()
1854	conn_log_msg(c, chan_lc, m_kicked(prefix, chan, comment))
1855	else:
1856	if chan_lc not in channels_dict:
1857	conn_error(c, 'KICK %s from unknown channel %s by %s [%s]'
1858	% (kicked_user, chan, prefix, comment))
1859	return
1860	try:
1861	channels_dict[chan_lc].remove(kicked_user_lc)
1862	except KeyError:
1863	conn_error(c, 'KICK non-member %s from %s by %s [%s]'
1864	% (kicked_user, chan, prefix, comment))
1865	return
1866	conn_log_msg(c, chan_lc,
1867	m_kick(prefix, chan, kicked_user, comment))
1868
1869	def nick():
1870	if len(params) != 1:
1871	conn_error(c, 'NICK with bad parameter count: %s' % msg)
1872	return
1873	new_nick, = params
1874	if prefix is None:
1875	conn_error(c, 'NICK without sender: %s' % msg)
1876	return
1877	sender = sender_nick(prefix)
1878	new_nick_lc = conn_casemap(c, new_nick)
1879	sender_lc = conn_casemap(c, sender)
1880	if sender_lc == conn_nick_lc(c):
1881	conn_info(c, 'nick changed to %s' % new_nick)
1882	conn_set_nick(c, new_nick)
1883	schedule_status_draw()
1884	for chan_lc, members in conn_channels(c).items():
1885	if sender_lc in members:
1886	members.remove(sender_lc)
1887	members.add(new_nick_lc)
1888	conn_log_msg(c, chan_lc, m_nick(sender, new_nick))
1889
1890	def topic():
1891	if len(params) != 2:
1892	conn_error(c, '(RPL_(NO))TOPIC with bad parameter count: %s' % msg)
1893	chan = params[0]
1894	topic = None
1895	if cmd != str(RPL_NOTOPIC):
1896	topic = params[1]
1897	chan_lc = conn_casemap(c, chan)
1898	if chan_lc in conn_channels(c):
1899	buf_set_title(get_buf(chan_lc, conn_network(c)), topic or chan_lc)
1900	conn_log_msg(c, chan_lc, m_topic(prefix or '', topic))
1901	else:
1902	conn_log_msg(c, None, m_chantopic(prefix or '', chan, topic))
1903
1904	def unknown_command():
1905	conn_info(c, 'unknown command from server: %s' % msg)
1906
1907	def unknown_reply():
1908	conn_log_msg(c, None, m_server(prefix or '', ' '.join([cmd] + params)))
1909
1910	if len(cmd) == 3 and all(map(is_digit, cmd)):
1911	# Replies
1912	if not params:
1913	conn_error(c, 'reply %s with no destination' % cmd)
1914	return
1915	destination = params.pop(0)
1916	{
1917	RPL_WELCOME: welcome,
1918	RPL_NAMREPLY: names_reply,
1919	RPL_ENDOFNAMES: end_names,
1920	RPL_TOPIC: topic,
1921	RPL_NOTOPIC: topic,
1922	#ERR_NICKNAMEINUSE:
1923	#ERR_NICKCOLLISION:
1924	#ERR_NOTREGISTERED:
1925	}.get(int(cmd), unknown_reply)()
1926	else:
1927	{
1928	'error': error_msg,
1929	'ping': ping,
1930	'pong': pong,
1931	'privmsg': privmsg,
1932	'notice': privmsg,
1933	'join': join,
1934	'mode': mode,
1935	'part': part,
1936	'quit': quit_msg,
1937	'kick': kick,
1938	'nick': nick,
1939	'topic': topic,
1940	}.get(cmd, unknown_command)()
1941
1942	def conn_join(c, chan, key=None):
1943	conn_info(c, 'joining %s' % chan)
1944	conn_send(c, 'JOIN', [chan] if key is None else [chan, key])
1945
1946	def conn_privmsg(c, target, msg):
1947	# There is NO SANE WAY to deduce the max privmsg length, go figure.
1948	for line in wrap(msg, 400):
1949	conn_log_msg(c, target, m_privmsg(conn_nick(c), line))
1950	conn_send(c, 'PRIVMSG', [target, line])
1951
1952	def conn_ping(c):
1953	conn_set_ping_ts(c, mono_time())
1954	conn_send(c, 'PING', [conn_nick(c)])
1955	conn_run_in(c, PING_TIMEOUT, conn_timeout)
1956
1957	def conn_timeout(c):
1958	if mono_time() - conn_pong_ts(c) > PING_TIMEOUT:
1959	conn_error(c, 'ping timed out')
1960	conn_close(c)
1961
1962	def conn_reg_timeout(c):
1963	if mono_time() - max(conn_pong_ts(c), conn_ping_ts(c)) > PING_TIMEOUT:
1964	conn_error(c, 'registration timed out')
1965	conn_close(c)
1966
1967	# Log file message formatting is simpler than UI as the message type and
1968	# sender are always shown explicitly.
1969	arg2 = lambda a, b: b
1970	arg3 = lambda a, b, c: c
1971	empty2 = lambda a, b: ''
1972	def lterr(*_):
1973	raise TypeError('bad log message type')
1974
1975	format_log_msg = matcher(message, (
1976	(m_privmsg, arg2),
1977	(m_notice, arg2),
1978	(m_join, empty2),
1979	(m_part, arg3),
1980	(m_quit, arg2),
1981	(m_nick, arg2),
1982	(m_kick, lambda sender, chan, name, msg: name + ' ' + msg),
1983	(m_kicked, arg3),
1984	(m_topic, lambda sender, topic: topic or ''),
1985	(m_chantopic, lterr),
1986	(m_mode, lterr),
1987	(m_chanmode, arg3),
1988	(m_names, arg3),
1989	(m_endnames, empty2),
1990	(m_error, arg2),
1991	(m_client, lterr),
1992	(m_server, arg2)))
1993
1994	def file_log_msg(network, venue, m):
1995	if venue is None or len(venue) == 0:
1996	return
1997	path = ('logs', network, fs_encode(venue) + '.log')
1998	# Possible optimization: cache log FDs and check freshness by comparing
1999	# (dev, inode) with stat() on each write. Exceeding the max FDs rlimit
2000	# would need to be handled, e.g. by LRU eviction using a minheap with
2001	# global write counter.
2002	def open_log():
2003	return os_open('/'.join(path), O_WRONLY \| O_APPEND \| O_CREAT, 0666)
2004	try:
2005	try:
2006	fd = open_log()
2007	except EnvironmentError, e:
2008	if e.errno != ENOENT:
2009	raise
2010	try:
2011	mkdir(path[0])
2012	except EnvironmentError, e:
2013	if e.errno != EEXIST:
2014	raise
2015	mkdir('/'.join(path[:2]))
2016	fd = open_log()
2017	try:
2018	write_all(fd, ''.join((
2019	str(int(time()*100)),
2020	' ', variant_name(m),
2021	' <', variant_args(m)[0], '> ', format_log_msg(m), LF)))
2022	except EnvironmentError, e:
2023	error(e)
2024	close(fd)
2025	except EnvironmentError, e:
2026	error(e)
2027
2028	def handle_resize(*_):
2029	global scr_height, scr_width
2030	scr_height, scr_width = t.screen_size()
2031	schedule_redraw()
2032	try:
2033	write(self_pipe_wr, '\0')
2034	except EnvironmentError, e:
2035	if e.errno not in (EAGAIN, EWOULDBLOCK):
2036	raise
2037
2038	# Poor man's monotonic clock. Doesn't give real time, but at least avoids
2039	# overly delayed events if the clock is stepped backward.
2040	mono_last = mono_offset = 0
2041	def mono_time(time_=time):
2042	global mono_last, mono_offset
2043	now = time_() + mono_offset
2044	if now < mono_last:
2045	mono_offset += mono_last - now
2046	now = mono_last
2047	mono_last = now
2048	return now
2049
2050	schedule = []
2051	run_in = lambda seconds, thunk: heap_insert(schedule, mono_time() + seconds,
2052	thunk)
2053
2054	def main():
2055	yrc_home = getenv('HOME', '') + '/.yrc'
2056	try:
2057	chdir(yrc_home)
2058	except EnvironmentError:
2059	mkdir(yrc_home)
2060	chdir(yrc_home)
2061
2062	set_nonblock(self_pipe_rd)
2063	set_nonblock(self_pipe_wr)
2064	signal(SIGINT, SIG_DFL)
2065	signal(SIGWINCH, handle_resize)
2066	handle_resize()
2067
2068	info('Welcome to yrc: the Unix IRC client')
2069	info('Version: %s' % __version__)
2070	info('Documentation is included in the distribution: refer to README and '
2071	+ "manual.txt to get started, or NEWS for what's new in this release")
2072	info('Type /quit<Enter> to exit')
2073	prompt_enter()
2074
2075	while not quit_flag():
2076	refresh_if_needed()
2077	timeout = None
2078	if schedule:
2079	timeout = max(0, heap_peek(schedule)[0] - mono_time())
2080	try:
2081	readers, writers, _ = select(
2082	[STDIN, self_pipe_rd] + open_conns.keys(),
2083	opening_conns.keys() +
2084	[fd for fd, c in open_conns.items() if conn_wrbuf(c)],
2085	(), timeout)
2086	except SelectError, e:
2087	if e[0] == EINTR:
2088	continue
2089	raise
2090	for fd in readers:
2091	if fd == STDIN:
2092	try:
2093	data = read_all(fd)
2094	except (EOFError, EnvironmentError):
2095	schedule_quit()
2096	for c in data:
2097	kbd_state(c)
2098	elif fd == self_pipe_rd:
2099	read_all(self_pipe_rd)
2100	elif fd in open_conns:
2101	c = open_conns[fd]
2102	try:
2103	data = read_all(fd)
2104	except EOFError:
2105	conn_info(c, 'connection closed by server')
2106	conn_close(c)
2107	except EnvironmentError, e:
2108	conn_error(c, str(e))
2109	conn_close(c)
2110	else:
2111	conn_handle_data(c, data)
2112	for fd in writers:
2113	if fd in opening_conns:
2114	conn_handle_connected(opening_conns[fd])
2115	elif fd in open_conns:
2116	c = open_conns[fd]
2117	try:
2118	n = write(fd, conn_wrbuf(c))
2119	except EnvironmentError, e:
2120	if e.errno not in (EAGAIN, EWOULDBLOCK):
2121	conn_error(c, str(e))
2122	conn_close(c)
2123	else:
2124	conn_wrbuf_rm(c, n)
2125	while schedule and heap_peek(schedule)[0] < mono_time():
2126	heap_extract(schedule)[1]()
2127
2128	def crash_handler():
2129	cleanup = t.init(nonblock_read=True)
2130	try:
2131	main()
2132	finally:
2133	cleanup()
2134
2135	check_command_dicts((
2136	GLOBAL_KEYS,
2137	PROMPT_KEYS,
2138	BUFLIST_KEYS,
2139	BUF_KEYS,
2140	CMD_ABBREVS
2141	))