def _can_allocate(struct):
""" Checks that select structs can be allocated by the underlying
operating system, not just advertised by the select module. We don't
check select() because we'll be hopeful that most platforms that
don't have it available will not advertise it. (ie: GAE) """
try:
# select.poll() objects won't fail until used.
if struct == 'poll':
p = select.poll()
p.poll(0)
# All others will fail on allocation.
else:
getattr(select, struct)().close()
return True
except (OSError, AttributeError) as e:
return False
# Choose the best implementation, roughly:
# kqueue == epoll > poll > select. Devpoll not supported. (See above)
# select() also can't accept a FD > FD_SETSIZE (usually around 1024)
python类kqueue()的实例源码
def DefaultSelector():
""" This function serves as a first call for DefaultSelector to
detect if the select module is being monkey-patched incorrectly
by eventlet, greenlet, and preserve proper behavior. """
global _DEFAULT_SELECTOR
if _DEFAULT_SELECTOR is None:
if _can_allocate('kqueue'):
_DEFAULT_SELECTOR = KqueueSelector
elif _can_allocate('epoll'):
_DEFAULT_SELECTOR = EpollSelector
elif _can_allocate('poll'):
_DEFAULT_SELECTOR = PollSelector
elif hasattr(select, 'select'):
_DEFAULT_SELECTOR = SelectSelector
else: # Platform-specific: AppEngine
raise ValueError('Platform does not have a selector')
return _DEFAULT_SELECTOR()
def _can_allocate(struct):
""" Checks that select structs can be allocated by the underlying
operating system, not just advertised by the select module. We don't
check select() because we'll be hopeful that most platforms that
don't have it available will not advertise it. (ie: GAE) """
try:
# select.poll() objects won't fail until used.
if struct == 'poll':
p = select.poll()
p.poll(0)
# All others will fail on allocation.
else:
getattr(select, struct)().close()
return True
except (OSError, AttributeError) as e:
return False
# Choose the best implementation, roughly:
# kqueue == epoll > poll > select. Devpoll not supported. (See above)
# select() also can't accept a FD > FD_SETSIZE (usually around 1024)
def DefaultSelector():
""" This function serves as a first call for DefaultSelector to
detect if the select module is being monkey-patched incorrectly
by eventlet, greenlet, and preserve proper behavior. """
global _DEFAULT_SELECTOR
if _DEFAULT_SELECTOR is None:
if _can_allocate('kqueue'):
_DEFAULT_SELECTOR = KqueueSelector
elif _can_allocate('epoll'):
_DEFAULT_SELECTOR = EpollSelector
elif _can_allocate('poll'):
_DEFAULT_SELECTOR = PollSelector
elif hasattr(select, 'select'):
_DEFAULT_SELECTOR = SelectSelector
else: # Platform-specific: AppEngine
raise ValueError('Platform does not have a selector')
return _DEFAULT_SELECTOR()
def _can_allocate(struct):
""" Checks that select structs can be allocated by the underlying
operating system, not just advertised by the select module. We don't
check select() because we'll be hopeful that most platforms that
don't have it available will not advertise it. (ie: GAE) """
try:
# select.poll() objects won't fail until used.
if struct == 'poll':
p = select.poll()
p.poll(0)
# All others will fail on allocation.
else:
getattr(select, struct)().close()
return True
except (OSError, AttributeError) as e:
return False
# Choose the best implementation, roughly:
# kqueue == epoll > poll > select. Devpoll not supported. (See above)
# select() also can't accept a FD > FD_SETSIZE (usually around 1024)
def DefaultSelector():
""" This function serves as a first call for DefaultSelector to
detect if the select module is being monkey-patched incorrectly
by eventlet, greenlet, and preserve proper behavior. """
global _DEFAULT_SELECTOR
if _DEFAULT_SELECTOR is None:
if _can_allocate('kqueue'):
_DEFAULT_SELECTOR = KqueueSelector
elif _can_allocate('epoll'):
_DEFAULT_SELECTOR = EpollSelector
elif _can_allocate('poll'):
_DEFAULT_SELECTOR = PollSelector
elif hasattr(select, 'select'):
_DEFAULT_SELECTOR = SelectSelector
else: # Platform-specific: AppEngine
raise ValueError('Platform does not have a selector')
return _DEFAULT_SELECTOR()
def __init__(self):
if hasattr(select, 'epoll'):
self._impl = select.epoll()
model = 'epoll'
elif hasattr(select, 'kqueue'):
self._impl = KqueueLoop()
model = 'kqueue'
elif hasattr(select, 'select'):
self._impl = SelectLoop()
model = 'select'
else:
raise Exception('can not find any available functions in select '
'package')
self._fdmap = {} # (f, handler)
self._last_time = time.time()
self._periodic_callbacks = []
self._stopping = False
logging.debug('using event model: %s', model)
def poll(self, timeout):
kevents = self._kqueue.control(None, 1000, timeout)
events = {}
for kevent in kevents:
fd = kevent.ident
if kevent.filter == select.KQ_FILTER_READ:
events[fd] = events.get(fd, 0) | IOLoop.READ
if kevent.filter == select.KQ_FILTER_WRITE:
if kevent.flags & select.KQ_EV_EOF:
# If an asynchronous connection is refused, kqueue
# returns a write event with the EOF flag set.
# Turn this into an error for consistency with the
# other IOLoop implementations.
# Note that for read events, EOF may be returned before
# all data has been consumed from the socket buffer,
# so we only check for EOF on write events.
events[fd] = IOLoop.ERROR
else:
events[fd] = events.get(fd, 0) | IOLoop.WRITE
if kevent.flags & select.KQ_EV_ERROR:
events[fd] = events.get(fd, 0) | IOLoop.ERROR
return events.items()
def poll(self, timeout):
kevents = self._kqueue.control(None, 1000, timeout)
events = {}
for kevent in kevents:
fd = kevent.ident
if kevent.filter == select.KQ_FILTER_READ:
events[fd] = events.get(fd, 0) | IOLoop.READ
if kevent.filter == select.KQ_FILTER_WRITE:
if kevent.flags & select.KQ_EV_EOF:
# If an asynchronous connection is refused, kqueue
# returns a write event with the EOF flag set.
# Turn this into an error for consistency with the
# other IOLoop implementations.
# Note that for read events, EOF may be returned before
# all data has been consumed from the socket buffer,
# so we only check for EOF on write events.
events[fd] = IOLoop.ERROR
else:
events[fd] = events.get(fd, 0) | IOLoop.WRITE
if kevent.flags & select.KQ_EV_ERROR:
events[fd] = events.get(fd, 0) | IOLoop.ERROR
return events.items()
def _can_allocate(struct):
""" Checks that select structs can be allocated by the underlying
operating system, not just advertised by the select module. We don't
check select() because we'll be hopeful that most platforms that
don't have it available will not advertise it. (ie: GAE) """
try:
# select.poll() objects won't fail until used.
if struct == 'poll':
p = select.poll()
p.poll(0)
# All others will fail on allocation.
else:
getattr(select, struct)().close()
return True
except (OSError, AttributeError) as e:
return False
# Choose the best implementation, roughly:
# kqueue == epoll > poll > select. Devpoll not supported. (See above)
# select() also can't accept a FD > FD_SETSIZE (usually around 1024)
def DefaultSelector():
""" This function serves as a first call for DefaultSelector to
detect if the select module is being monkey-patched incorrectly
by eventlet, greenlet, and preserve proper behavior. """
global _DEFAULT_SELECTOR
if _DEFAULT_SELECTOR is None:
if _can_allocate('kqueue'):
_DEFAULT_SELECTOR = KqueueSelector
elif _can_allocate('epoll'):
_DEFAULT_SELECTOR = EpollSelector
elif _can_allocate('poll'):
_DEFAULT_SELECTOR = PollSelector
elif hasattr(select, 'select'):
_DEFAULT_SELECTOR = SelectSelector
else: # Platform-specific: AppEngine
raise ValueError('Platform does not have a selector')
return _DEFAULT_SELECTOR()
def _can_allocate(struct):
""" Checks that select structs can be allocated by the underlying
operating system, not just advertised by the select module. We don't
check select() because we'll be hopeful that most platforms that
don't have it available will not advertise it. (ie: GAE) """
try:
# select.poll() objects won't fail until used.
if struct == 'poll':
p = select.poll()
p.poll(0)
# All others will fail on allocation.
else:
getattr(select, struct)().close()
return True
except (OSError, AttributeError) as e:
return False
# Choose the best implementation, roughly:
# kqueue == epoll > poll > select. Devpoll not supported. (See above)
# select() also can't accept a FD > FD_SETSIZE (usually around 1024)
def DefaultSelector():
""" This function serves as a first call for DefaultSelector to
detect if the select module is being monkey-patched incorrectly
by eventlet, greenlet, and preserve proper behavior. """
global _DEFAULT_SELECTOR
if _DEFAULT_SELECTOR is None:
if _can_allocate('kqueue'):
_DEFAULT_SELECTOR = KqueueSelector
elif _can_allocate('epoll'):
_DEFAULT_SELECTOR = EpollSelector
elif _can_allocate('poll'):
_DEFAULT_SELECTOR = PollSelector
elif hasattr(select, 'select'):
_DEFAULT_SELECTOR = SelectSelector
else: # Platform-specific: AppEngine
raise ValueError('Platform does not have a selector')
return _DEFAULT_SELECTOR()
def __init__(self):
if hasattr(select, 'epoll'):
self._impl = select.epoll()
model = 'epoll'
elif hasattr(select, 'kqueue'):
self._impl = KqueueLoop()
model = 'kqueue'
elif hasattr(select, 'select'):
self._impl = SelectLoop()
model = 'select'
else:
raise Exception('can not find any available functions in select '
'package')
self._fdmap = {} # (f, handler)
self._last_time = time.time()
self._periodic_callbacks = []
self._stopping = False
logging.debug('using event model: %s', model)
def __init__(self):
if hasattr(select, 'epoll'):
self._impl = select.epoll()
model = 'epoll'
elif hasattr(select, 'kqueue'):
self._impl = KqueueLoop()
model = 'kqueue'
elif hasattr(select, 'select'):
self._impl = SelectLoop()
model = 'select'
else:
raise Exception('can not find any available functions in select '
'package')
self._fdmap = {} # (f, handler)
self._last_time = time.time()
self._periodic_callbacks = []
self._stopping = False
logging.debug('using event model: %s', model)
def _can_allocate(struct):
""" Checks that select structs can be allocated by the underlying
operating system, not just advertised by the select module. We don't
check select() because we'll be hopeful that most platforms that
don't have it available will not advertise it. (ie: GAE) """
try:
# select.poll() objects won't fail until used.
if struct == 'poll':
p = select.poll()
p.poll(0)
# All others will fail on allocation.
else:
getattr(select, struct)().close()
return True
except (OSError, AttributeError) as e:
return False
# Choose the best implementation, roughly:
# kqueue == epoll > poll > select. Devpoll not supported. (See above)
# select() also can't accept a FD > FD_SETSIZE (usually around 1024)
def DefaultSelector():
""" This function serves as a first call for DefaultSelector to
detect if the select module is being monkey-patched incorrectly
by eventlet, greenlet, and preserve proper behavior. """
global _DEFAULT_SELECTOR
if _DEFAULT_SELECTOR is None:
if _can_allocate('kqueue'):
_DEFAULT_SELECTOR = KqueueSelector
elif _can_allocate('epoll'):
_DEFAULT_SELECTOR = EpollSelector
elif _can_allocate('poll'):
_DEFAULT_SELECTOR = PollSelector
elif hasattr(select, 'select'):
_DEFAULT_SELECTOR = SelectSelector
else: # Platform-specific: AppEngine
raise ValueError('Platform does not have a selector')
return _DEFAULT_SELECTOR()
def _can_allocate(struct):
""" Checks that select structs can be allocated by the underlying
operating system, not just advertised by the select module. We don't
check select() because we'll be hopeful that most platforms that
don't have it available will not advertise it. (ie: GAE) """
try:
# select.poll() objects won't fail until used.
if struct == 'poll':
p = select.poll()
p.poll(0)
# All others will fail on allocation.
else:
getattr(select, struct)().close()
return True
except (OSError, AttributeError) as e:
return False
# Choose the best implementation, roughly:
# kqueue == epoll > poll > select. Devpoll not supported. (See above)
# select() also can't accept a FD > FD_SETSIZE (usually around 1024)
def DefaultSelector():
""" This function serves as a first call for DefaultSelector to
detect if the select module is being monkey-patched incorrectly
by eventlet, greenlet, and preserve proper behavior. """
global _DEFAULT_SELECTOR
if _DEFAULT_SELECTOR is None:
if _can_allocate('kqueue'):
_DEFAULT_SELECTOR = KqueueSelector
elif _can_allocate('epoll'):
_DEFAULT_SELECTOR = EpollSelector
elif _can_allocate('poll'):
_DEFAULT_SELECTOR = PollSelector
elif hasattr(select, 'select'):
_DEFAULT_SELECTOR = SelectSelector
else: # Platform-specific: AppEngine
raise ValueError('Platform does not have a selector')
return _DEFAULT_SELECTOR()
def _can_allocate(struct):
""" Checks that select structs can be allocated by the underlying
operating system, not just advertised by the select module. We don't
check select() because we'll be hopeful that most platforms that
don't have it available will not advertise it. (ie: GAE) """
try:
# select.poll() objects won't fail until used.
if struct == 'poll':
p = select.poll()
p.poll(0)
# All others will fail on allocation.
else:
getattr(select, struct)().close()
return True
except (OSError, AttributeError) as e:
return False
# Choose the best implementation, roughly:
# kqueue == epoll > poll > select. Devpoll not supported. (See above)
# select() also can't accept a FD > FD_SETSIZE (usually around 1024)
def DefaultSelector():
""" This function serves as a first call for DefaultSelector to
detect if the select module is being monkey-patched incorrectly
by eventlet, greenlet, and preserve proper behavior. """
global _DEFAULT_SELECTOR
if _DEFAULT_SELECTOR is None:
if _can_allocate('kqueue'):
_DEFAULT_SELECTOR = KqueueSelector
elif _can_allocate('epoll'):
_DEFAULT_SELECTOR = EpollSelector
elif _can_allocate('poll'):
_DEFAULT_SELECTOR = PollSelector
elif hasattr(select, 'select'):
_DEFAULT_SELECTOR = SelectSelector
else: # Platform-specific: AppEngine
raise ValueError('Platform does not have a selector')
return _DEFAULT_SELECTOR()
def DefaultSelector():
""" This function serves as a first call for DefaultSelector to
detect if the select module is being monkey-patched incorrectly
by eventlet, greenlet, and preserve proper behavior. """
global _DEFAULT_SELECTOR
if _DEFAULT_SELECTOR is None:
if platform.python_implementation() == 'Jython': # Platform-specific: Jython
_DEFAULT_SELECTOR = JythonSelectSelector
elif _can_allocate('kqueue'):
_DEFAULT_SELECTOR = KqueueSelector
elif _can_allocate('devpoll'):
_DEFAULT_SELECTOR = DevpollSelector
elif _can_allocate('epoll'):
_DEFAULT_SELECTOR = EpollSelector
elif _can_allocate('poll'):
_DEFAULT_SELECTOR = PollSelector
elif hasattr(select, 'select'):
_DEFAULT_SELECTOR = SelectSelector
else: # Platform-specific: AppEngine
raise RuntimeError('Platform does not have a selector.')
return _DEFAULT_SELECTOR()
def _can_allocate(struct):
""" Checks that select structs can be allocated by the underlying
operating system, not just advertised by the select module. We don't
check select() because we'll be hopeful that most platforms that
don't have it available will not advertise it. (ie: GAE) """
try:
# select.poll() objects won't fail until used.
if struct == 'poll':
p = select.poll()
p.poll(0)
# All others will fail on allocation.
else:
getattr(select, struct)().close()
return True
except (OSError, AttributeError) as e:
return False
# Choose the best implementation, roughly:
# kqueue == epoll > poll > select. Devpoll not supported. (See above)
# select() also can't accept a FD > FD_SETSIZE (usually around 1024)
def DefaultSelector():
""" This function serves as a first call for DefaultSelector to
detect if the select module is being monkey-patched incorrectly
by eventlet, greenlet, and preserve proper behavior. """
global _DEFAULT_SELECTOR
if _DEFAULT_SELECTOR is None:
if _can_allocate('kqueue'):
_DEFAULT_SELECTOR = KqueueSelector
elif _can_allocate('epoll'):
_DEFAULT_SELECTOR = EpollSelector
elif _can_allocate('poll'):
_DEFAULT_SELECTOR = PollSelector
elif hasattr(select, 'select'):
_DEFAULT_SELECTOR = SelectSelector
else: # Platform-specific: AppEngine
raise ValueError('Platform does not have a selector')
return _DEFAULT_SELECTOR()
def __init__(self):
platform = sys.platform
if platform.find("win32") > -1 or platform.find("cygwin") > -1:
self.__async_mode = "select"
self.__iowait_func = self.__select_iowait
if platform.find("darwin") > -1 or platform.find("freebsd") > -1:
self.__async_mode = "kqueue"
self.__kqueue_object = select.kqueue()
self.__iowait_func = self.__kqueue_iowait
if platform.find("linux") > -1:
self.__async_mode = "epoll"
self.__epoll_object = select.epoll()
self.__iowait_func = self.__epoll_iowait
return
def _can_allocate(struct):
""" Checks that select structs can be allocated by the underlying
operating system, not just advertised by the select module. We don't
check select() because we'll be hopeful that most platforms that
don't have it available will not advertise it. (ie: GAE) """
try:
# select.poll() objects won't fail until used.
if struct == 'poll':
p = select.poll()
p.poll(0)
# All others will fail on allocation.
else:
getattr(select, struct)().close()
return True
except (OSError, AttributeError) as e:
return False
# Choose the best implementation, roughly:
# kqueue == epoll > poll > select. Devpoll not supported. (See above)
# select() also can't accept a FD > FD_SETSIZE (usually around 1024)
def DefaultSelector():
""" This function serves as a first call for DefaultSelector to
detect if the select module is being monkey-patched incorrectly
by eventlet, greenlet, and preserve proper behavior. """
global _DEFAULT_SELECTOR
if _DEFAULT_SELECTOR is None:
if _can_allocate('kqueue'):
_DEFAULT_SELECTOR = KqueueSelector
elif _can_allocate('epoll'):
_DEFAULT_SELECTOR = EpollSelector
elif _can_allocate('poll'):
_DEFAULT_SELECTOR = PollSelector
elif hasattr(select, 'select'):
_DEFAULT_SELECTOR = SelectSelector
else: # Platform-specific: AppEngine
raise ValueError('Platform does not have a selector')
return _DEFAULT_SELECTOR()
def _can_allocate(struct):
""" Checks that select structs can be allocated by the underlying
operating system, not just advertised by the select module. We don't
check select() because we'll be hopeful that most platforms that
don't have it available will not advertise it. (ie: GAE) """
try:
# select.poll() objects won't fail until used.
if struct == 'poll':
p = select.poll()
p.poll(0)
# All others will fail on allocation.
else:
getattr(select, struct)().close()
return True
except (OSError, AttributeError) as e:
return False
# Choose the best implementation, roughly:
# kqueue == epoll > poll > select. Devpoll not supported. (See above)
# select() also can't accept a FD > FD_SETSIZE (usually around 1024)
def DefaultSelector():
""" This function serves as a first call for DefaultSelector to
detect if the select module is being monkey-patched incorrectly
by eventlet, greenlet, and preserve proper behavior. """
global _DEFAULT_SELECTOR
if _DEFAULT_SELECTOR is None:
if _can_allocate('kqueue'):
_DEFAULT_SELECTOR = KqueueSelector
elif _can_allocate('epoll'):
_DEFAULT_SELECTOR = EpollSelector
elif _can_allocate('poll'):
_DEFAULT_SELECTOR = PollSelector
elif hasattr(select, 'select'):
_DEFAULT_SELECTOR = SelectSelector
else: # Platform-specific: AppEngine
raise ValueError('Platform does not have a selector')
return _DEFAULT_SELECTOR()
def __init__(self):
if hasattr(select, 'epoll'):
self._impl = select.epoll()
model = 'epoll'
elif hasattr(select, 'kqueue'):
self._impl = KqueueLoop()
model = 'kqueue'
elif hasattr(select, 'select'):
self._impl = SelectLoop()
model = 'select'
else:
raise Exception('can not find any available functions in select '
'package')
self._fdmap = {} # (f, handler)
self._last_time = time.time()
self._periodic_callbacks = []
self._stopping = False
logging.debug('using event model: %s', model)
