John Snow beb6b57b3b python: create qemu packages
move python/qemu/*.py to python/qemu/[machine, qmp, utils]/*.py and
update import directives across the tree.

This is done to create a PEP420 namespace package, in which we may
create subpackages. To do this, the namespace directory ("qemu") should
not have any modules in it. Those files will go into new 'machine',
'qmp' and 'utils' subpackages instead.

Implement machine/__init__.py making the top-level classes and functions
from its various modules available directly inside the package. Change
qmp.py to qmp/__init__.py similarly, such that all of the useful QMP
library classes are available directly from "qemu.qmp" instead of
"qemu.qmp.qmp".

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-id: 20210527211715.394144-10-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2021-06-01 16:21:21 -04:00

161 lines
4.5 KiB
Python

"""
QEMU qtest library
qtest offers the QEMUQtestProtocol and QEMUQTestMachine classes, which
offer a connection to QEMU's qtest protocol socket, and a qtest-enabled
subclass of QEMUMachine, respectively.
"""
# Copyright (C) 2015 Red Hat Inc.
#
# Authors:
# Fam Zheng <famz@redhat.com>
#
# This work is licensed under the terms of the GNU GPL, version 2. See
# the COPYING file in the top-level directory.
#
# Based on qmp.py.
#
import os
import socket
from typing import (
List,
Optional,
Sequence,
TextIO,
)
from qemu.qmp import SocketAddrT
from .machine import QEMUMachine
class QEMUQtestProtocol:
"""
QEMUQtestProtocol implements a connection to a qtest socket.
:param address: QEMU address, can be either a unix socket path (string)
or a tuple in the form ( address, port ) for a TCP
connection
:param server: server mode, listens on the socket (bool)
:raise socket.error: on socket connection errors
.. note::
No conection is estabalished by __init__(), this is done
by the connect() or accept() methods.
"""
def __init__(self, address: SocketAddrT,
server: bool = False):
self._address = address
self._sock = self._get_sock()
self._sockfile: Optional[TextIO] = None
if server:
self._sock.bind(self._address)
self._sock.listen(1)
def _get_sock(self) -> socket.socket:
if isinstance(self._address, tuple):
family = socket.AF_INET
else:
family = socket.AF_UNIX
return socket.socket(family, socket.SOCK_STREAM)
def connect(self) -> None:
"""
Connect to the qtest socket.
@raise socket.error on socket connection errors
"""
self._sock.connect(self._address)
self._sockfile = self._sock.makefile(mode='r')
def accept(self) -> None:
"""
Await connection from QEMU.
@raise socket.error on socket connection errors
"""
self._sock, _ = self._sock.accept()
self._sockfile = self._sock.makefile(mode='r')
def cmd(self, qtest_cmd: str) -> str:
"""
Send a qtest command on the wire.
@param qtest_cmd: qtest command text to be sent
"""
assert self._sockfile is not None
self._sock.sendall((qtest_cmd + "\n").encode('utf-8'))
resp = self._sockfile.readline()
return resp
def close(self) -> None:
"""
Close this socket.
"""
self._sock.close()
if self._sockfile:
self._sockfile.close()
self._sockfile = None
def settimeout(self, timeout: Optional[float]) -> None:
"""Set a timeout, in seconds."""
self._sock.settimeout(timeout)
class QEMUQtestMachine(QEMUMachine):
"""
A QEMU VM, with a qtest socket available.
"""
def __init__(self,
binary: str,
args: Sequence[str] = (),
name: Optional[str] = None,
base_temp_dir: str = "/var/tmp",
socket_scm_helper: Optional[str] = None,
sock_dir: Optional[str] = None):
if name is None:
name = "qemu-%d" % os.getpid()
if sock_dir is None:
sock_dir = base_temp_dir
super().__init__(binary, args, name=name, base_temp_dir=base_temp_dir,
socket_scm_helper=socket_scm_helper,
sock_dir=sock_dir)
self._qtest: Optional[QEMUQtestProtocol] = None
self._qtest_path = os.path.join(sock_dir, name + "-qtest.sock")
@property
def _base_args(self) -> List[str]:
args = super()._base_args
args.extend([
'-qtest', f"unix:path={self._qtest_path}",
'-accel', 'qtest'
])
return args
def _pre_launch(self) -> None:
super()._pre_launch()
self._qtest = QEMUQtestProtocol(self._qtest_path, server=True)
def _post_launch(self) -> None:
assert self._qtest is not None
super()._post_launch()
self._qtest.accept()
def _post_shutdown(self) -> None:
super()._post_shutdown()
self._remove_if_exists(self._qtest_path)
def qtest(self, cmd: str) -> str:
"""
Send a qtest command to the guest.
:param cmd: qtest command to send
:return: qtest server response
"""
if self._qtest is None:
raise RuntimeError("qtest socket not available")
return self._qtest.cmd(cmd)