One-KVM/kvmd/aiogp.py
2025-02-03 12:55:28 +08:00

124 lines
4.3 KiB
Python

# ========================================================================== #
# #
# KVMD - The main PiKVM daemon. #
# #
# Copyright (C) 2018-2024 Maxim Devaev <mdevaev@gmail.com> #
# #
# This program is free software: you can redistribute it and/or modify #
# it under the terms of the GNU General Public License as published by #
# the Free Software Foundation, either version 3 of the License, or #
# (at your option) any later version. #
# #
# This program is distributed in the hope that it will be useful, #
# but WITHOUT ANY WARRANTY; without even the implied warranty of #
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the #
# GNU General Public License for more details. #
# #
# You should have received a copy of the GNU General Public License #
# along with this program. If not, see <https://www.gnu.org/licenses/>. #
# #
# ========================================================================== #
import asyncio
import threading
import dataclasses
#import gpiod
from . import aiotools
# =====
@dataclasses.dataclass(frozen=True)
class AioReaderPinParams:
inverted: bool
debounce: float
class AioReader: # pylint: disable=too-many-instance-attributes
def __init__(
self,
path: str,
consumer: str,
pins: dict[int, AioReaderPinParams],
notifier: aiotools.AioNotifier,
) -> None:
self.__path = path
self.__consumer = consumer
self.__pins = dict(pins)
self.__notifier = notifier
self.__values: (dict[int, _DebouncedValue] | None) = None
self.__thread = threading.Thread(target=self.__run, daemon=True)
self.__stop_event = threading.Event()
self.__loop: (asyncio.AbstractEventLoop | None) = None
def get(self, pin: int) -> bool:
value = (self.__values[pin].get() if self.__values is not None else False)
return (value ^ self.__pins[pin].inverted)
async def poll(self) -> None:
if not self.__pins:
await aiotools.wait_infinite()
else:
assert self.__loop is None
self.__loop = asyncio.get_running_loop()
self.__thread.start()
try:
await aiotools.run_async(self.__thread.join)
finally:
self.__stop_event.set()
await aiotools.run_async(self.__thread.join)
def __run(self) -> None:
assert self.__values is None
assert self.__loop
pins = sorted(self.__pins)
class _DebouncedValue:
def __init__(
self,
initial: bool,
debounce: float,
notifier: aiotools.AioNotifier,
loop: asyncio.AbstractEventLoop,
) -> None:
self.__value = initial
self.__debounce = debounce
self.__notifier = notifier
self.__loop = loop
self.__queue: "asyncio.Queue[bool]" = asyncio.Queue() # type: ignore
self.__task = loop.create_task(self.__consumer_task_loop())
def set(self, value: bool) -> None:
if self.__loop.is_running():
self.__check_alive()
self.__loop.call_soon_threadsafe(self.__queue.put_nowait, value)
def get(self) -> bool:
return self.__value
def __check_alive(self) -> None:
if self.__task.done() and not self.__task.cancelled():
raise RuntimeError("Dead debounce consumer")
async def __consumer_task_loop(self) -> None:
while True:
value = await self.__queue.get()
while not self.__queue.empty():
value = await self.__queue.get()
if self.__value != value:
self.__value = value
self.__notifier.notify()
await asyncio.sleep(self.__debounce)