circuitpython/extmod/uasyncio/event.py
Damien George caaff940a2 extmod/uasyncio: Rename and merge TaskQueue push/pop methods.
These are internal names and can be safely renamed without affecting user
code.  push_sorted() and push_head() are merged into a single push()
method, which is already how the C version is implemented.  pop_head() is
simply renamed to pop().

The changes are:
- q.push_sorted(task, t) -> q.push(task, t)
- q.push_head(task) -> q.push(task)
- q.pop_head() -> q.pop()

The shorter names and removal of push_head() leads to a code size reduction
of between 40 and 64 bytes on bare-metal targets.

Signed-off-by: Damien George <damien@micropython.org>
2022-04-22 16:37:02 +10:00

62 lines
1.9 KiB
Python

# MicroPython uasyncio module
# MIT license; Copyright (c) 2019-2020 Damien P. George
from . import core
# Event class for primitive events that can be waited on, set, and cleared
class Event:
def __init__(self):
self.state = False # False=unset; True=set
self.waiting = core.TaskQueue() # Queue of Tasks waiting on completion of this event
def is_set(self):
return self.state
def set(self):
# Event becomes set, schedule any tasks waiting on it
# Note: This must not be called from anything except the thread running
# the asyncio loop (i.e. neither hard or soft IRQ, or a different thread).
while self.waiting.peek():
core._task_queue.push(self.waiting.pop())
self.state = True
def clear(self):
self.state = False
async def wait(self):
if not self.state:
# Event not set, put the calling task on the event's waiting queue
self.waiting.push(core.cur_task)
# Set calling task's data to the event's queue so it can be removed if needed
core.cur_task.data = self.waiting
yield
return True
# MicroPython-extension: This can be set from outside the asyncio event loop,
# such as other threads, IRQs or scheduler context. Implementation is a stream
# that asyncio will poll until a flag is set.
# Note: Unlike Event, this is self-clearing.
try:
import uio
class ThreadSafeFlag(uio.IOBase):
def __init__(self):
self._flag = 0
def ioctl(self, req, flags):
if req == 3: # MP_STREAM_POLL
return self._flag * flags
return None
def set(self):
self._flag = 1
async def wait(self):
if not self._flag:
yield core._io_queue.queue_read(self)
self._flag = 0
except ImportError:
pass