Files
deb-python-eventlet/eventlet/hubs/libevent.py
Ryan Williams b46075bb80 Cleanup
2009-08-02 23:12:44 -07:00

225 lines
7.3 KiB
Python

# Copyright (c) 2007, Linden Research, Inc.
# Copyright (c) 2009 Denis Bilenko
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
import sys
import time
import traceback
import event
from eventlet import api
class event_wrapper(object):
def __init__(self, impl=None, seconds=None):
self.impl = impl
self.seconds = seconds
def __repr__(self):
if self.impl is not None:
return repr(self.impl)
else:
return object.__repr__(self)
def __str__(self):
if self.impl is not None:
return str(self.impl)
else:
return object.__str__(self)
def cancel(self):
if self.impl is not None:
self.impl.delete()
self.impl = None
class Hub(object):
SYSTEM_EXCEPTIONS = (KeyboardInterrupt, SystemExit)
def __init__(self, clock=time.time):
event.init()
self.clock = clock
self.readers = {}
self.writers = {}
self.greenlet = api.Greenlet(self.run)
self.signal_exc_info = None
self.signal(2, lambda signalnum, frame: self.greenlet.parent.throw(KeyboardInterrupt))
self.events_to_add = []
def closed(self, fd):
pass
def switch(self):
cur = api.getcurrent()
assert cur is not self.greenlet, 'Cannot switch to MAINLOOP from MAINLOOP'
switch_out = getattr(cur, 'switch_out', None)
if switch_out is not None:
try:
switch_out()
except:
traceback.print_exception(*sys.exc_info())
if self.greenlet.dead:
self.greenlet = api.Greenlet(self.run)
try:
api.getcurrent().parent = self.greenlet
except ValueError:
pass
return self.greenlet.switch()
def dispatch(self):
loop = event.loop
while True:
for e in self.events_to_add:
if e is not None and e.impl is not None and e.seconds is not None:
e.impl.add(e.seconds)
e.seconds = None
self.events_to_add = []
result = loop()
if getattr(event, '__event_exc', None) is not None:
# only have to do this because of bug in event.loop
t = getattr(event, '__event_exc')
setattr(event, '__event_exc', None)
assert getattr(event, '__event_exc') is None
raise t[0], t[1], t[2]
if result != 0:
return result
def run(self):
while True:
try:
self.dispatch()
except api.GreenletExit:
break
except self.SYSTEM_EXCEPTIONS:
raise
except:
if self.signal_exc_info is not None:
self.schedule_call_global(0, api.getcurrent().parent.throw, *self.signal_exc_info)
self.signal_exc_info = None
else:
traceback.print_exc()
def abort(self):
self.schedule_call_global(0, self.greenlet.throw, api.GreenletExit)
@property
def running(self):
return bool(self.greenlet)
def add_reader(self, fileno, read_cb):
""" Signals an intent to read from a particular file descriptor.
The *fileno* argument is the file number of the file of interest.
The *read_cb* argument is the callback which will be called when the file
is ready for reading.
"""
self.readers[fileno] = event.read(fileno, read_cb, fileno)
def add_writer(self, fileno, write_cb):
""" Signals an intent to write to a particular file descriptor.
The *fileno* argument is the file number of the file of interest.
The *write_cb* argument is the callback which will be called when the file
is ready for writing.
"""
self.readers[fileno] = event.write(fileno, write_cb, fileno)
def signal(self, signalnum, handler):
def wrapper():
try:
handler(signalnum, None)
except:
self.signal_exc_info = sys.exc_info()
event.abort()
return event_wrapper(event.signal(signalnum, wrapper))
def remove_descriptor(self, fileno):
reader = self.readers.pop(fileno, None)
if reader is not None:
try:
reader.delete()
except:
traceback.print_exc()
writer = self.writers.pop(fileno, None)
if writer is not None:
try:
writer.delete()
except:
traceback.print_exc()
def schedule_call_local(self, seconds, cb, *args, **kwargs):
current = api.getcurrent()
if current is self.greenlet:
return self.schedule_call_global(seconds, cb, *args, **kwargs)
event_impl = event.event(_scheduled_call_local, (cb, args, kwargs, current))
wrapper = event_wrapper(event_impl, seconds=seconds)
self.events_to_add.append(wrapper)
return wrapper
schedule_call = schedule_call_local
def schedule_call_global(self, seconds, cb, *args, **kwargs):
event_impl = event.event(_scheduled_call, (cb, args, kwargs))
wrapper = event_wrapper(event_impl, seconds=seconds)
self.events_to_add.append(wrapper)
return wrapper
def get_readers(self):
return self.readers
def get_writers(self):
return self.writers
def _version_info(self):
baseversion = event.__version__
try:
from ctypes import CDLL, util, c_char_p
c = CDLL(util.find_library('event'))
c.event_get_version.restype = c_char_p
baseversion += '/libevent=%s' % (c.event_get_version(), )
c.event_get_method.restype = c_char_p
baseversion += '/method=%s' % (c.event_get_method(), )
except Exception, ex:
print ex or type(ex).__name__
return baseversion
def _scheduled_call(event_impl, handle, evtype, arg):
cb, args, kwargs = arg
try:
cb(*args, **kwargs)
finally:
event_impl.delete()
def _scheduled_call_local(event_impl, handle, evtype, arg):
cb, args, kwargs, caller_greenlet = arg
try:
if not caller_greenlet.dead:
cb(*args, **kwargs)
finally:
event_impl.delete()