Robert Foley <robert.fo...@linaro.org> writes:
> The primary purpose of this change is to clean up
> machine.py's console_socket property to return a single type,
> a ConsoleSocket.
>
> ConsoleSocket now derives from a socket, which means that
> in the default case (of not draining), machine.py
> will see the same behavior as it did prior to ConsoleSocket.
>
> Signed-off-by: Robert Foley <robert.fo...@linaro.org>
> ---
> python/qemu/console_socket.py | 81 +++++++++++++++++++++--------------
> python/qemu/machine.py | 13 ++----
> 2 files changed, 54 insertions(+), 40 deletions(-)
>
> diff --git a/python/qemu/console_socket.py b/python/qemu/console_socket.py
> index 6a746c1dbf..475de5b101 100644
> --- a/python/qemu/console_socket.py
> +++ b/python/qemu/console_socket.py
> @@ -13,68 +13,76 @@ which can drain a socket and optionally dump the bytes to
> file.
> # the COPYING file in the top-level directory.
> #
>
> -import asyncore
> import socket
> import threading
> from collections import deque
> import time
>
>
> -class ConsoleSocket(asyncore.dispatcher):
> +class ConsoleSocket(socket.socket):
> """
> ConsoleSocket represents a socket attached to a char device.
>
> - Drains the socket and places the bytes into an in memory buffer
> - for later processing.
> + Optionally (if drain==True), drains the socket and places the bytes
> + into an in memory buffer for later processing.
>
> Optionally a file path can be passed in and we will also
> dump the characters to this file for debugging purposes.
> """
> - def __init__(self, address, file=None):
> + def __init__(self, address, file=None, drain=False):
> self._recv_timeout_sec = 300
> self._sleep_time = 0.5
> self._buffer = deque()
> - self._asyncore_thread = None
> - self._sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
> - self._sock.connect(address)
> + self._drain_thread = None
> + socket.socket.__init__(self, socket.AF_UNIX, socket.SOCK_STREAM)
> + self.connect(address)
> + self._drain = drain
We end up with two variables that represent the fact we have draining
happening. Could we rationalise it into:
if drain:
self._drain_thread = self._thread_start()
else
self._drain_thread = None # if this is needed
And then tests for:
if not self._drain:
become
if self._drain_thread is None:
> self._logfile = None
> if file:
> self._logfile = open(file, "w")
> - asyncore.dispatcher.__init__(self, sock=self._sock)
> self._open = True
> - self._thread_start()
> + if drain:
> + self._thread_start()
> +
> + def _drain_fn(self):
> + """Drains the socket and runs while the socket is open."""
> + while self._open:
> + try:
> + self._drain_socket()
> + except socket.timeout:
> + # The socket is expected to timeout since we set a
> + # short timeout to allow the thread to exit when
> + # self._open is set to False.
> + time.sleep(self._sleep_time)
>
> def _thread_start(self):
> - """Kick off a thread to wait on the asyncore.loop"""
> - if self._asyncore_thread is not None:
> + """Kick off a thread to drain the socket."""
> + if self._drain_thread is not None:
> return
> - self._asyncore_thread = threading.Thread(target=asyncore.loop,
> - kwargs={'timeout':1})
> - self._asyncore_thread.daemon = True
> - self._asyncore_thread.start()
> -
> - def handle_close(self):
> - """redirect close to base class"""
> - # Call the base class close, but not self.close() since
> - # handle_close() occurs in the context of the thread which
> - # self.close() attempts to join.
> - asyncore.dispatcher.close(self)
> + # Configure socket to not block and timeout.
> + # This allows our drain thread to not block
> + # on recieve and exit smoothly.
> + socket.socket.setblocking(self, 0)
> + socket.socket.settimeout(self, 1)
> + self._drain_thread = threading.Thread(target=self._drain_fn)
> + self._drain_thread.daemon = True
> + self._drain_thread.start()
>
> def close(self):
> """Close the base object and wait for the thread to terminate"""
> if self._open:
> self._open = False
> - asyncore.dispatcher.close(self)
> - if self._asyncore_thread is not None:
> - thread, self._asyncore_thread = self._asyncore_thread, None
> + if self._drain and self._drain_thread is not None:
> + thread, self._drain_thread = self._drain_thread, None
Would self._drain ever not have self._drain_thread set?
> thread.join()
> + socket.socket.close(self)
<snip>
> diff --git a/python/qemu/machine.py b/python/qemu/machine.py
> index 6769359766..62709d86e4 100644
> --- a/python/qemu/machine.py
> +++ b/python/qemu/machine.py
> @@ -22,7 +22,6 @@ import logging
> import os
> import subprocess
> import shutil
> -import socket
FYI minor patch conflict here with master
> import tempfile
> from typing import Optional, Type
> from types import TracebackType
> @@ -591,12 +590,8 @@ class QEMUMachine:
> Returns a socket connected to the console
> """
> if self._console_socket is None:
> - if self._drain_console:
> - self._console_socket = console_socket.ConsoleSocket(
> - self._console_address,
> - file=self._console_log_path)
> - else:
> - self._console_socket = socket.socket(socket.AF_UNIX,
> - socket.SOCK_STREAM)
> - self._console_socket.connect(self._console_address)
> + self._console_socket = console_socket.ConsoleSocket(
> + self._console_address,
> + file=self._console_log_path,
> + drain=self._drain_console)
> return self._console_socket
--
Alex Bennée
