def put(self, item, block=True, timeout=None):
"""Put an item into the queue.
If optional arg `block` is true and `timeout` is ``None`` (the default),
block if necessary until a free slot is available. If `timeout` is
a positive number, it blocks at most `timeout` seconds and raises
the :class:`queue.Full` exception if no free slot was available within that time.
Otherwise (`block` is false), put an item on the queue if a free slot
is immediately available, else raise the :class:`queue.Full` exception (`timeout`
is ignored in that case).
"""
if self.maxsize is None or self.qsize() < self.maxsize:
# there's a free slot, put an item right away
self._put(item)
if self.getters:
self._schedule_unlock()
elif not block and get_hub() is greenlet.getcurrent():
# we're in the mainloop, so we cannot wait; we can switch() to other greenlets though
# find a getter and deliver an item to it
while self.getters:
getter = self.getters.pop()
if getter:
self._put(item)
item = self._get()
getter.switch(item)
return
raise Full
elif block:
waiter = ItemWaiter(item)
self.putters.add(waiter)
timeout = Timeout(timeout, Full)
try:
if self.getters:
self._schedule_unlock()
result = waiter.wait()
assert result is waiter, "Invalid switch into Queue.put: %r" % (
result, )
if waiter.item is not _NONE:
self._put(item)
finally:
timeout.cancel()
self.putters.discard(waiter)
else:
raise Full
def put(self, item, block=True, timeout=None):
"""Put an item into the queue.
If optional arg `block` is true and `timeout` is ``None`` (the default),
block if necessary until a free slot is available. If `timeout` is
a positive number, it blocks at most `timeout` seconds and raises
the :class:`queue.Full` exception if no free slot was available within that time.
Otherwise (`block` is false), put an item on the queue if a free slot
is immediately available, else raise the :class:`queue.Full` exception (`timeout`
is ignored in that case).
"""
if self.maxsize is None or self.qsize() < self.maxsize:
# there's a free slot, put an item right away
self._put(item)
if self.getters:
self._schedule_unlock()
elif not block and get_hub() is greenlet.getcurrent():
# we're in the mainloop, so we cannot wait; we can switch() to other greenlets though
# find a getter and deliver an item to it
while self.getters:
getter = self.getters.pop()
if getter:
self._put(item)
item = self._get()
getter.switch(item)
return
raise Full
elif block:
waiter = ItemWaiter(item)
self.putters.add(waiter)
timeout = Timeout(timeout, Full)
try:
if self.getters:
self._schedule_unlock()
result = waiter.wait()
assert result is waiter, "Invalid switch into Queue.put: %r" % (result, )
if waiter.item is not _NONE:
self._put(item)
finally:
timeout.cancel()
self.putters.discard(waiter)
else:
raise Full
def get(self, block=True, timeout=None):
"""Remove and return an item from the queue.
If optional args `block` is true and `timeout` is ``None`` (the default),
block if necessary until an item is available. If `timeout` is a positive number,
it blocks at most `timeout` seconds and raises the :class:`queue.Empty` exception
if no item was available within that time. Otherwise (`block` is false), return
an item if one is immediately available, else raise the :class:`queue.Empty` exception
(`timeout` is ignored in that case).
"""
if self.qsize():
if self.putters:
self._schedule_unlock()
return self._get()
elif not block and get_hub() is greenlet.getcurrent():
# special case to make get_nowait() runnable in the mainloop greenlet
# there are no items in the queue; try to fix the situation by unlocking putters
while self.putters:
putter = self.putters.pop()
if putter:
putter.switch(putter)
if self.qsize():
return self._get()
raise Empty
elif block:
waiter = Waiter()
timeout = Timeout(timeout, Empty)
try:
self.getters.add(waiter)
if self.putters:
self._schedule_unlock()
return waiter.wait()
finally:
self.getters.discard(waiter)
timeout.cancel()
else:
raise Empty
def get(self, block=True, timeout=None):
"""Remove and return an item from the queue.
If optional args `block` is true and `timeout` is ``None`` (the default),
block if necessary until an item is available. If `timeout` is a positive number,
it blocks at most `timeout` seconds and raises the :class:`queue.Empty` exception
if no item was available within that time. Otherwise (`block` is false), return
an item if one is immediately available, else raise the :class:`queue.Empty` exception
(`timeout` is ignored in that case).
"""
if self.qsize():
if self.putters:
self._schedule_unlock()
return self._get()
elif not block and get_hub() is greenlet.getcurrent():
# special case to make get_nowait() runnable in the mainloop greenlet
# there are no items in the queue; try to fix the situation by unlocking putters
while self.putters:
putter = self.putters.pop()
if putter:
putter.switch(putter)
if self.qsize():
return self._get()
raise Empty
elif block:
waiter = Waiter()
timeout = Timeout(timeout, Empty)
try:
self.getters.add(waiter)
if self.putters:
self._schedule_unlock()
return waiter.wait()
finally:
self.getters.discard(waiter)
timeout.cancel()
else:
raise Empty