Files
deb-python-eventlet/eventlet/hubs/poll.py

88 lines
2.6 KiB
Python

import sys
import select
import errno
from time import sleep
import time
from eventlet.hubs.hub import BaseHub, READ, WRITE
EXC_MASK = select.POLLERR | select.POLLHUP
READ_MASK = select.POLLIN
WRITE_MASK = select.POLLOUT
class Hub(BaseHub):
def __init__(self, clock=time.time):
super(Hub, self).__init__(clock)
self.poll = select.poll()
def add(self, evtype, fileno, cb):
oldlisteners = self.listeners[evtype].get(fileno)
listener = super(Hub, self).add(evtype, fileno, cb)
if not oldlisteners:
# Means we've added a new listener
self.register(fileno)
return listener
def remove(self, listener):
super(Hub, self).remove(listener)
self.register(listener.fileno)
def register(self, fileno):
mask = 0
if self.listeners[READ].get(fileno):
mask |= READ_MASK
if self.listeners[WRITE].get(fileno):
mask |= WRITE_MASK
if mask:
self.poll.register(fileno, mask)
else:
try:
self.poll.unregister(fileno)
except KeyError:
pass
def remove_descriptor(self, fileno):
super(Hub, self).remove_descriptor(fileno)
try:
self.poll.unregister(fileno)
except KeyError:
pass
def wait(self, seconds=None):
readers = self.listeners[READ]
writers = self.listeners[WRITE]
if not readers and not writers:
if seconds:
sleep(seconds)
return
try:
presult = self.poll.poll(seconds * 1000.0)
except select.error, e:
if e.args[0] == errno.EINTR:
return
raise
SYSTEM_EXCEPTIONS = self.SYSTEM_EXCEPTIONS
for fileno, event in presult:
try:
if event & READ_MASK:
readers[fileno][0](fileno)
if event & WRITE_MASK:
writers[fileno][0](fileno)
if event & select.POLLNVAL:
self.remove_descriptor(fileno)
continue
if event & EXC_MASK:
for listeners in (readers.get(fileno, []),
writers.get(fileno, [])):
for listener in listeners:
listener(fileno)
except KeyError:
pass
except SYSTEM_EXCEPTIONS:
raise
except:
self.squelch_exception(fileno, sys.exc_info())