From e8c37ba0a52dd6e5699a86318b1a63189892dde2 Mon Sep 17 00:00:00 2001
From: steering7253
Date: Fri, 12 Jun 2026 19:12:08 -0600
Subject: support ISUPPORT LINELEN

---
 http2irc.py | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/http2irc.py b/http2irc.py
index 7a38122..15f21a3 100644
--- a/http2irc.py
+++ b/http2irc.py
@@ -374,6 +374,7 @@ class IRCClientProtocol(asyncio.Protocol):
 		self.whoxReply = [] # List of (nickname, account) tuples from the currently running WHO query
 		self.whoxStartTime = None
 		self.userChannels = collections.defaultdict(set) # List of which channels a user is known to be in; nickname:str -> {channel:str, ...}
+		self.linelen = 510
 
 	@staticmethod
 	def nick_command(nick: str):
@@ -402,13 +403,13 @@ class IRCClientProtocol(asyncio.Protocol):
 		# command: b'JOIN' or b'PART'; channels: set[str]
 
 		channels = [x.encode('utf-8') for x in channels]
-		if len(command) + sum(1 + len(x) for x in channels) <= 510: # Total length = command + (separator + channel name for each channel, where the separator is a space for the first and then a comma)
+		if len(command) + sum(1 + len(x) for x in channels) <= self.linelen: # Total length = command + (separator + channel name for each channel, where the separator is a space for the first and then a comma)
 			# Everything fits into one command.
 			self.send(command + b' ' + b','.join(channels))
 			return
 
 		# List too long, need to split.
-		limit = 510 - len(command)
+		limit = self.linelen - len(command)
 		lengths = [1 + len(x) for x in channels]  # separator + channel name
 		chanLengthAcceptable = [l <= limit for l in lengths]
 		if not all(chanLengthAcceptable):
@@ -444,8 +445,8 @@ class IRCClientProtocol(asyncio.Protocol):
 
 	def send(self, data):
 		self.logger.debug(f'Queueing for send: {data!r}')
-		if len(data) > 510:
-			raise RuntimeError(f'IRC message too long ({len(data)} > 510): {data!r}')
+		if len(data) > self.linelen:
+			raise RuntimeError(f'IRC message too long ({len(data)} > {self.linelen}): {data!r}')
 		self.sendQueue.put_nowait(data)
 
 	def _direct_send(self, data):
@@ -529,12 +530,12 @@ class IRCClientProtocol(asyncio.Protocol):
 			channelB = channel.encode('utf-8')
 			messageB = message.encode('utf-8')
 			usermaskPrefixLength = 1 + self._self_usermask_length() + 1 # :usermask<SP>
-			if usermaskPrefixLength + len(b'PRIVMSG ' + channelB + b' :' + messageB) > 510:
+			if usermaskPrefixLength + len(b'PRIVMSG ' + channelB + b' :' + messageB) > self.linelen:
 				# Message too long, need to split or truncate. First try to split on spaces, then on codepoints. Ideally, would use graphemes between, but that's too complicated.
 				self.logger.debug(f'Message too long, overlongmode = {overlongmode}')
 				prefix = b'PRIVMSG ' + channelB + b' :'
 				prefixLength = usermaskPrefixLength + len(prefix) # Need to account for the origin prefix included by the ircd when sending to others
-				maxMessageLength = 510 - prefixLength # maximum length of the message part within each line
+				maxMessageLength = self.linelen - prefixLength # maximum length of the message part within each line
 				if overlongmode == 'truncate':
 					maxMessageLength -= 3 # Make room for an ellipsis at the end
 				messages = []
@@ -553,7 +554,7 @@ class IRCClientProtocol(asyncio.Protocol):
 						continue
 
 					# No space found, need to search for a suitable codepoint location.
-					pMessage = message[:maxMessageLength] # at most 510 codepoints which expand to at least 510 bytes
+					pMessage = message[:maxMessageLength] # at most linelen codepoints which expand to at least linelen bytes
 					pLengths = [len(x.encode('utf-8')) for x in pMessage] # byte size of each codepoint
 					pRunningLengths = list(itertools.accumulate(pLengths)) # byte size up to each codepoint
 					if pRunningLengths[-1] <= maxMessageLength: # Special case: entire pMessage is short enough
@@ -657,6 +658,13 @@ class IRCClientProtocol(asyncio.Protocol):
 			self.logger.error('SASL error, terminating connection')
 			self.transport.close()
 
+		elif line.command in (ircstates.numerics.RPL_ENDOFMOTD, ircstates.numerics.ERR_NOMOTD):
+			if 'LINELEN' in self.server.isupport.raw:
+				try:
+					self.linelen = int(self.server.isupport.raw['LINELEN'])-2
+				except ValueError as e:
+					self.logger.error(f'IRC server sent invalid LINELEN, ignoring: {value}')
+
 		# NICK errors
 		elif line.command in ('431', ircstates.numerics.ERR_ERRONEUSNICKNAME, ircstates.numerics.ERR_NICKNAMEINUSE, '436'):
 			self.logger.error(f'Failed to set nickname: {message!r}, terminating connection')
-- 
cgit v1.3.1-10-gc9f91