Implement the concept of the frame dispatcher and handlers
This commit is contained in:
parent
05c71259f6
commit
af18b58e1f
|
@ -0,0 +1,122 @@
|
||||||
|
# This file is a part of sedbgmux, an open source DebugMux client.
|
||||||
|
# Copyright (c) 2022 Vadim Yanitskiy <axilirator@gmail.com>
|
||||||
|
#
|
||||||
|
# SPDX-License-Identifier: GPL-3.0-or-later
|
||||||
|
#
|
||||||
|
# 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 <http://www.gnu.org/licenses/>.
|
||||||
|
|
||||||
|
import logging as log
|
||||||
|
import threading
|
||||||
|
import queue
|
||||||
|
import enum
|
||||||
|
import abc
|
||||||
|
|
||||||
|
from typing import Any, Optional
|
||||||
|
from construct import Container
|
||||||
|
from proto import DbgMuxFrame
|
||||||
|
|
||||||
|
|
||||||
|
class DbgMuxFrameHandler(abc.ABC):
|
||||||
|
''' Abstract DebugMux frame handler '''
|
||||||
|
|
||||||
|
_tx_queue: Optional[queue.Queue] = None
|
||||||
|
|
||||||
|
def send(self, msg_type: DbgMuxFrame.MsgType, msg: Any = b''):
|
||||||
|
''' Called by child classes to send some message '''
|
||||||
|
assert self._tx_queue is not None
|
||||||
|
self._tx_queue.put((msg_type, msg))
|
||||||
|
|
||||||
|
@abc.abstractmethod
|
||||||
|
def _handle_frame(self, frame: Container) -> None:
|
||||||
|
''' Handle the given DebugMux frame '''
|
||||||
|
|
||||||
|
|
||||||
|
class ConnState(enum.Enum):
|
||||||
|
''' Connection state for DbgMuxConnHandler '''
|
||||||
|
NotEstablished = enum.auto()
|
||||||
|
Establishing = enum.auto()
|
||||||
|
Established = enum.auto()
|
||||||
|
|
||||||
|
|
||||||
|
class DbgMuxConnHandler(DbgMuxFrameHandler):
|
||||||
|
''' Abstract DebugMux connection handler '''
|
||||||
|
|
||||||
|
def __init__(self):
|
||||||
|
self.conn_state: ConnState = ConnState.NotEstablished
|
||||||
|
self.ConnRef: int = 0xffff
|
||||||
|
self.DPRef: int = 0xffff
|
||||||
|
|
||||||
|
def establish(self, DPRef: int) -> None:
|
||||||
|
assert self.conn_state == ConnState.NotEstablished
|
||||||
|
log.info("Establishing connection with DPRef=0x%04x", DPRef)
|
||||||
|
self.send(DbgMuxFrame.MsgType.ConnEstablish, dict(DPRef=DPRef))
|
||||||
|
self.conn_state = ConnState.Establishing
|
||||||
|
self.DPRef = DPRef
|
||||||
|
|
||||||
|
def send_data(self, data: bytes) -> None:
|
||||||
|
''' Called by child classes to send connection data '''
|
||||||
|
assert self.conn_state == ConnState.Established
|
||||||
|
msg = dict(ConnRef=self.ConnRef, Data=data)
|
||||||
|
self.send(DbgMuxFrame.MsgType.ConnData, msg)
|
||||||
|
|
||||||
|
def _match(self, frame: Container,
|
||||||
|
msg_type: DbgMuxFrame.MsgType,
|
||||||
|
msg_fields: dict = { }) -> bool:
|
||||||
|
if frame['MsgType'] != msg_type:
|
||||||
|
return False
|
||||||
|
for (key, val) in msg_fields.items():
|
||||||
|
if key not in frame['Msg']:
|
||||||
|
return False
|
||||||
|
if frame['Msg'][key] != val:
|
||||||
|
return False
|
||||||
|
return True
|
||||||
|
|
||||||
|
def _handle_frame(self, frame: Container) -> None:
|
||||||
|
''' Handle the given DebugMux frame '''
|
||||||
|
|
||||||
|
if self.conn_state == ConnState.Established:
|
||||||
|
fields = dict(ConnRef=self.ConnRef)
|
||||||
|
if self._match(frame, DbgMuxFrame.MsgType.ConnData, fields):
|
||||||
|
self._handle_data(frame['Msg']['Data'])
|
||||||
|
self.send(DbgMuxFrame.MsgType.Ack)
|
||||||
|
raise StopIteration
|
||||||
|
elif self._match(frame, DbgMuxFrame.MsgType.ConnTerminated, fields):
|
||||||
|
log.info('Connection terminated (DPRef=0x%04x, ConnRef=0x%04x)',
|
||||||
|
self.DPRef, self.ConnRef)
|
||||||
|
self.conn_state = ConnState.NotEstablished
|
||||||
|
self._handle_terminate()
|
||||||
|
self.send(DbgMuxFrame.MsgType.Ack)
|
||||||
|
raise StopIteration
|
||||||
|
elif self.conn_state == ConnState.Establishing:
|
||||||
|
# Match ConnEstablished with our DPRef and any ConnRef
|
||||||
|
if self._match(frame, DbgMuxFrame.MsgType.ConnEstablished, dict(DPRef=self.DPRef)):
|
||||||
|
log.info('Connection established (DPRef=0x%04x, ConnRef=0x%04x)',
|
||||||
|
self.DPRef, frame['Msg']['ConnRef'])
|
||||||
|
self.conn_state = ConnState.Established
|
||||||
|
self.ConnRef = frame['Msg']['ConnRef']
|
||||||
|
self._handle_establish()
|
||||||
|
self.send(DbgMuxFrame.MsgType.Ack)
|
||||||
|
raise StopIteration
|
||||||
|
|
||||||
|
@abc.abstractmethod
|
||||||
|
def _handle_data(self, data: bytes) -> None:
|
||||||
|
''' Called on reciept of connection data '''
|
||||||
|
|
||||||
|
@abc.abstractmethod
|
||||||
|
def _handle_establish(self) -> None:
|
||||||
|
''' Called on connection establishment '''
|
||||||
|
|
||||||
|
@abc.abstractmethod
|
||||||
|
def _handle_terminate(self) -> None:
|
||||||
|
''' Called on connection termination '''
|
69
peer.py
69
peer.py
|
@ -23,10 +23,73 @@ import queue
|
||||||
from typing import Any, Optional
|
from typing import Any, Optional
|
||||||
from construct import Const, Container, Int16ul
|
from construct import Const, Container, Int16ul
|
||||||
|
|
||||||
|
from handlers import DbgMuxFrameHandler
|
||||||
from transport import Transport
|
from transport import Transport
|
||||||
from proto import DbgMuxFrame
|
from proto import DbgMuxFrame
|
||||||
|
|
||||||
|
|
||||||
|
class DbgMuxFrameDisp:
|
||||||
|
''' DebugMux frame dispatcher '''
|
||||||
|
|
||||||
|
def __init__(self, rxq: queue.Queue, txq: queue.Queue):
|
||||||
|
self.__hlist = list()
|
||||||
|
self._rx_queue = rxq
|
||||||
|
self._tx_queue = txq
|
||||||
|
|
||||||
|
self._thread = threading.Thread(target=self._worker,
|
||||||
|
name='DbgMuxPeer-Disp',
|
||||||
|
daemon=True)
|
||||||
|
self._shutdown = threading.Event()
|
||||||
|
|
||||||
|
def start(self) -> None:
|
||||||
|
self._shutdown.clear()
|
||||||
|
self._thread.start()
|
||||||
|
|
||||||
|
def stop(self) -> None:
|
||||||
|
self._shutdown.set()
|
||||||
|
self._thread.join()
|
||||||
|
|
||||||
|
def find_by_name(self, name: str) -> Optional[DbgMuxFrameHandler]:
|
||||||
|
for (hname, hinst) in self.__hlist:
|
||||||
|
if hname == name:
|
||||||
|
return hinst
|
||||||
|
return None
|
||||||
|
|
||||||
|
def register(self, inst: DbgMuxFrameHandler,
|
||||||
|
name: Optional[str] = None) -> None:
|
||||||
|
if name is not None and self.find_by_name(name):
|
||||||
|
raise FileExistsError
|
||||||
|
self.__hlist.append((name, inst))
|
||||||
|
# Give a handler access to the Tx queue
|
||||||
|
inst._tx_queue = self._tx_queue
|
||||||
|
|
||||||
|
def unregister(self, name: str):
|
||||||
|
inst = self.find_by_name(name)
|
||||||
|
if inst is None:
|
||||||
|
raise FileNotFoundError
|
||||||
|
self.__hlist.remove((name, inst))
|
||||||
|
|
||||||
|
def _worker(self) -> None:
|
||||||
|
while not self._shutdown.is_set():
|
||||||
|
try:
|
||||||
|
frame = self._rx_queue.get(block=True, timeout=0.5)
|
||||||
|
self._dispatch(frame)
|
||||||
|
except queue.Empty:
|
||||||
|
pass
|
||||||
|
log.debug('Thread \'%s\' is shutting down', threading.current_thread().name)
|
||||||
|
|
||||||
|
def _dispatch(self, frame: DbgMuxFrame) -> None:
|
||||||
|
for (hname, hinst) in self.__hlist:
|
||||||
|
try:
|
||||||
|
hinst._handle_frame(frame)
|
||||||
|
except StopIteration:
|
||||||
|
return
|
||||||
|
except Exception as e:
|
||||||
|
log.error("Handler '%s' raised an exception: %s", hname, e)
|
||||||
|
# TODO: remove this handler?
|
||||||
|
log.error("DebugMux message %s was not handled, dropping...", frame['Msg'])
|
||||||
|
|
||||||
|
|
||||||
class DbgMuxPeer:
|
class DbgMuxPeer:
|
||||||
def __init__(self, io: Transport):
|
def __init__(self, io: Transport):
|
||||||
self.tx_count: int = 0
|
self.tx_count: int = 0
|
||||||
|
@ -40,13 +103,17 @@ class DbgMuxPeer:
|
||||||
self._tx_thread = threading.Thread(target=self._tx_worker,
|
self._tx_thread = threading.Thread(target=self._tx_worker,
|
||||||
name='DbgMuxPeer-Tx',
|
name='DbgMuxPeer-Tx',
|
||||||
daemon=True)
|
daemon=True)
|
||||||
|
|
||||||
self._shutdown = threading.Event()
|
self._shutdown = threading.Event()
|
||||||
|
|
||||||
# Internal queues for Rx/Tx frames
|
# Internal queues for Rx/Tx frames
|
||||||
self._rx_queue = queue.Queue()
|
self._rx_queue = queue.Queue()
|
||||||
self._tx_queue = queue.Queue()
|
self._tx_queue = queue.Queue()
|
||||||
|
|
||||||
|
# Init frame dispatcher
|
||||||
|
self.disp = DbgMuxFrameDisp(self._rx_queue,
|
||||||
|
self._tx_queue)
|
||||||
|
# TODO: self.disp.start()
|
||||||
|
|
||||||
def start(self) -> None:
|
def start(self) -> None:
|
||||||
self._shutdown.clear()
|
self._shutdown.clear()
|
||||||
self._rx_thread.start()
|
self._rx_thread.start()
|
||||||
|
|
Loading…
Reference in New Issue