def __check_and_die(self):
if not self.ptr:
# We've been destroyed during the middle of self.run().
# This method is being called into from C, and it's not
# safe to go back to C (Windows in particular can abort
# the process with "GetQueuedCompletionStatusEx: (6) The
# handle is invalid.") So switch to the parent greenlet.
getcurrent().parent.throw(LoopExit('Destroyed during run'))
def run(self):
"""
Entry-point to running the loop. This method is called automatically
when the hub greenlet is scheduled; do not call it directly.
:raises gevent.exceptions.LoopExit: If the loop finishes running. This means
that there are no other scheduled greenlets, and no active
watchers or servers. In some situations, this indicates a
programming error.
"""
assert self is getcurrent(), 'Do not call Hub.run() directly'
self.start_periodic_monitoring_thread()
while 1:
loop = self.loop
loop.error_handler = self
try:
loop.run()
finally:
loop.error_handler = None # break the refcount cycle
# This function must never return, as it will cause
# switch() in the parent greenlet to return an unexpected
# value. This can show up as unexpected failures e.g.,
# from Waiters raising AssertionError or MulitpleWaiter
# raising invalid IndexError.
#
# It is still possible to kill this greenlet with throw.
# However, in that case switching to it is no longer safe,
# as switch will return immediately.
#
# Note that there's a problem with simply doing
# ``self.parent.throw()`` and never actually exiting this
# greenlet: The greenlet tends to stay alive. This is
# because throwing the exception captures stack frames
# (regardless of what we do with the argument) and those
# get saved. In addition to this object having
# ``gr_frame`` pointing to this method, which contains
# ``self``, which points to the parent, and both of which point to
# an internal thread state dict that points back to the current greenlet for the thread,
# which is likely to be the parent: a cycle.
#
# We can't have ``join()`` tell us to finish, because we
# need to be able to resume after this throw. The only way
# to dispose of the greenlet is to use ``self.destroy()``.
debug = []
if hasattr(loop, 'debug'):
debug = loop.debug()
loop = None
self.parent.throw(LoopExit('This operation would block forever',
self,
debug))
# Execution could resume here if another blocking API call is made
# in the same thread and the hub hasn't been destroyed, so clean
# up anything left.
debug = None
def run(self):
"""
Entry-point to running the loop. This method is called automatically
when the hub greenlet is scheduled; do not call it directly.
:raises gevent.exceptions.LoopExit: If the loop finishes running. This means
that there are no other scheduled greenlets, and no active
watchers or servers. In some situations, this indicates a
programming error.
"""
assert self is getcurrent(), 'Do not call Hub.run() directly'
self.start_periodic_monitoring_thread()
while 1:
loop = self.loop
loop.error_handler = self
try:
loop.run()
finally:
loop.error_handler = None # break the refcount cycle
debug = []
if hasattr(loop, 'debug'):
debug = loop.debug()
self.parent.throw(LoopExit('This operation would block forever', self, debug))
