Limnoria/src/socketDrivers.py

###
# Copyright (c) 2002-2004, Jeremiah Fincher
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###

"""
Contains simple socket drivers.  Asyncore bugged (haha, pun!) me.
"""

from __future__ import division

__revision__ ="$Id$"

import supybot.fix as fix

import time
import select
import socket
from itertools import imap

import supybot.log as log
import supybot.conf as conf
import supybot.utils as utils
import supybot.world as world
import supybot.drivers as drivers
import supybot.schedule as schedule

reconnectWaits = (0, 60, 300)
class SocketDriver(drivers.IrcDriver, drivers.ServersMixin):
    def __init__(self, irc):
        self.irc = irc
        super(SocketDriver, self).__init__(irc)
        self.conn = None
        self.servers = ()
        self.eagains = 0
        self.inbuffer = ''
        self.outbuffer = ''
        self.zombie = False
        self.scheduled = None
        self.connected = False
        self.reconnectWaitsIndex = 0
        self.reconnectWaits = reconnectWaits
        self.connect()

    def _handleSocketError(self, e):
        # (11, 'Resource temporarily unavailable') raised if connect
        # hasn't finished yet.  We'll keep track of how many we get.
        if e.args[0] != 11 and self.eagains > 120:
            drivers.log.disconnect(self.currentServer, e)
            self.reconnect(wait=True)
        else:
            log.debug('Got EAGAIN, current count: %s.', self.eagains)
            self.eagains += 1

    def _sendIfMsgs(self):
        if not self.zombie:
            msgs = [self.irc.takeMsg()]
            while msgs[-1] is not None:
                msgs.append(self.irc.takeMsg())
            del msgs[-1]
            self.outbuffer += ''.join(imap(str, msgs))
        if self.outbuffer:
            try:
                sent = self.conn.send(self.outbuffer)
                self.outbuffer = self.outbuffer[sent:]
                self.eagains = 0
            except socket.error, e:
                self._handleSocketError(e)
        if self.zombie and not self.outbuffer:
            self._reallyDie()

    def run(self):
        if not self.connected:
            # We sleep here because otherwise, if we're the only driver, we'll
            # spin at 100% CPU while we're disconnected.
            time.sleep(conf.supybot.drivers.poll())
            return
        self._sendIfMsgs()
        try:
            self.inbuffer += self.conn.recv(1024)
            self.eagains = 0
            lines = self.inbuffer.split('\n')
            self.inbuffer = lines.pop()
            for line in lines:
                msg = drivers.parseMsg(line)
                if msg is not None:
                    self.irc.feedMsg(msg)
        except socket.timeout:
            pass
        except socket.error, e:
            self._handleSocketError(e)
            return
        if not self.irc.zombie:
            self._sendIfMsgs()

    def connect(self, **kwargs):
        self.reconnect(reset=False, **kwargs)
        
    def reconnect(self, wait=False, reset=True):
        self.scheduled = False
        if self.connected:
            drivers.log.reconnect(self.irc.network)
            self.conn.close()
            self.connected = False
        if reset:
            drivers.log.debug('Resetting %s.', self.irc)
            self.irc.reset()
        else:
            drivers.log.debug('Not resetting %s.', self.irc)
        if wait:
            self._scheduleReconnect()
            return
        server = self._getNextServer()
        drivers.log.connect(self.currentServer)
        try:
            self.conn = utils.getSocket(server[0])
        except socket.error, e:
            drivers.log.connectError(self.currentServer, e)
            self.reconnect(wait=True)
            return
        # We allow more time for the connect here, since it might take longer.
        # At least 10 seconds.
        self.conn.settimeout(max(10, conf.supybot.drivers.poll()*10))
        if self.reconnectWaitsIndex < len(self.reconnectWaits)-1:
            self.reconnectWaitsIndex += 1
        try:
            self.conn.connect(server)
            self.conn.settimeout(conf.supybot.drivers.poll())
        except socket.error, e:
            if e.args[0] == 115:
                now = time.time()
                when = now + 60
                whenS = log.timestamp(when)
                drivers.log.debug('Connection in progress, scheduling '
                                  'connectedness check for %s', whenS)
                schedule.addEvent(self._checkAndWriteOrReconnect, when)
            else:
                drivers.log.connectError(self.currentServer, e)
                self.reconnect(wait=True)
            return
        self.connected = True
        self.reconnectWaitPeriodsIndex = 0

    def _checkAndWriteOrReconnect(self):
        drivers.log.debug('Checking whether we are connected.')
        (_, w, _) = select.select([], [self.conn], [], 0)
        if w:
            drivers.log.debug('Socket is writable, it might be connected.')
            self.connected = True
            self.reconnectWaitPeriodsIndex = 0
        else:
            drivers.log.connectError(self.currentServer, 'Timed out')
            self.reconnect()

    def _scheduleReconnect(self):
        when = time.time() + self.reconnectWaits[self.reconnectWaitsIndex]
        if not world.dying:
            drivers.log.reconnect(self.irc.network, when)
        self.scheduled = schedule.addEvent(self.reconnect, when)

    def die(self):
        self.zombie = True
        if self.scheduled:
            schedule.removeEvent(self.scheduled)
        drivers.log.die(self.irc)
        
    def _reallyDie(self):
        if self.conn is not None:
            self.conn.close()
        drivers.IrcDriver.die(self)
        # self.irc.die() Kill off the ircs yourself, jerk!

    def name(self):
        return '%s(%s)' % (self.__class__.__name__, self.irc)


Driver = SocketDriver

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