No actual code changes, just several pylint/style fixes and docstring clarifications.
Signed-off-by: Lukáš Doktor <ldok...@redhat.com> --- scripts/qemu.py | 76 ++++++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 53 insertions(+), 23 deletions(-) diff --git a/scripts/qemu.py b/scripts/qemu.py index 880e3e8..466aaab 100644 --- a/scripts/qemu.py +++ b/scripts/qemu.py @@ -23,8 +23,22 @@ import qmp.qmp class QEMUMachine(object): '''A QEMU VM''' - def __init__(self, binary, args=[], wrapper=[], name=None, test_dir="/var/tmp", - monitor_address=None, socket_scm_helper=None, debug=False): + def __init__(self, binary, args=[], wrapper=[], name=None, + test_dir="/var/tmp", monitor_address=None, + socket_scm_helper=None, debug=False): + ''' + Create a QEMUMachine object + + @param binary: path to the qemu binary (str) + @param args: initial list of extra arguments + @param wrapper: list of arguments used as prefix to qemu binary + @param name: name of this object (used for log/monitor/... file names) + @param test_dir: base location to put log/monitor/... files in + @param monitor_address: custom address for QMP monitor + @param socket_scm_helper: path to scm_helper binary (to forward fds) + @param debug: enable debug mode (forwarded to QMP helper and such) + @note: Qemu process is not started until launch() is used. + ''' if name is None: name = "qemu-%d" % os.getpid() if monitor_address is None: @@ -33,12 +47,13 @@ class QEMUMachine(object): self._qemu_log_path = os.path.join(test_dir, name + ".log") self._popen = None self._binary = binary - self._args = list(args) # Force copy args in case we modify them + self._args = list(args) # Force copy args in case we modify them self._wrapper = wrapper self._events = [] self._iolog = None self._socket_scm_helper = socket_scm_helper self._debug = debug + self._qmp = None # This can be used to add an unused monitor instance. def add_monitor_telnet(self, ip, port): @@ -64,16 +79,16 @@ class QEMUMachine(object): if self._socket_scm_helper is None: print >>sys.stderr, "No path to socket_scm_helper set" return -1 - if os.path.exists(self._socket_scm_helper) == False: + if not os.path.exists(self._socket_scm_helper): print >>sys.stderr, "%s does not exist" % self._socket_scm_helper return -1 fd_param = ["%s" % self._socket_scm_helper, "%d" % self._qmp.get_sock_fd(), "%s" % fd_file_path] devnull = open('/dev/null', 'rb') - p = subprocess.Popen(fd_param, stdin=devnull, stdout=sys.stdout, - stderr=sys.stderr) - return p.wait() + proc = subprocess.Popen(fd_param, stdin=devnull, stdout=sys.stdout, + stderr=sys.stderr) + return proc.wait() @staticmethod def _remove_if_exists(path): @@ -99,8 +114,8 @@ class QEMUMachine(object): return self._popen.pid def _load_io_log(self): - with open(self._qemu_log_path, "r") as fh: - self._iolog = fh.read() + with open(self._qemu_log_path, "r") as iolog: + self._iolog = iolog.read() def _base_args(self): if isinstance(self._monitor_address, tuple): @@ -114,8 +129,8 @@ class QEMUMachine(object): '-display', 'none', '-vga', 'none'] def _pre_launch(self): - self._qmp = qmp.qmp.QEMUMonitorProtocol(self._monitor_address, server=True, - debug=self._debug) + self._qmp = qmp.qmp.QEMUMonitorProtocol(self._monitor_address, + server=True, debug=self._debug) def _post_launch(self): self._qmp.accept() @@ -131,9 +146,11 @@ class QEMUMachine(object): qemulog = open(self._qemu_log_path, 'wb') try: self._pre_launch() - args = self._wrapper + [self._binary] + self._base_args() + self._args + args = (self._wrapper + [self._binary] + self._base_args() + + self._args) self._popen = subprocess.Popen(args, stdin=devnull, stdout=qemulog, - stderr=subprocess.STDOUT, shell=False) + stderr=subprocess.STDOUT, + shell=False) self._post_launch() except: if self.is_running(): @@ -149,28 +166,34 @@ class QEMUMachine(object): try: self._qmp.cmd('quit') self._qmp.close() - except: + except: # kill VM on any failure pylint: disable=W0702 self._popen.kill() exitcode = self._popen.wait() if exitcode < 0: - sys.stderr.write('qemu received signal %i: %s\n' % (-exitcode, ' '.join(self._args))) + sys.stderr.write('qemu received signal %i: %s\n' + % (-exitcode, ' '.join(self._args))) self._load_io_log() self._post_shutdown() underscore_to_dash = string.maketrans('_', '-') + def qmp(self, cmd, conv_keys=True, **args): '''Invoke a QMP command and return the result dict''' qmp_args = dict() - for k in args.keys(): + for key in args.keys(): if conv_keys: - qmp_args[k.translate(self.underscore_to_dash)] = args[k] + qmp_args[key.translate(self.underscore_to_dash)] = args[key] else: - qmp_args[k] = args[k] + qmp_args[key] = args[key] return self._qmp.cmd(cmd, args=qmp_args) def command(self, cmd, conv_keys=True, **args): + ''' + Invoke a QMP command and on success return result dict or on failure + raise exception with details. + ''' reply = self.qmp(cmd, conv_keys, **args) if reply is None: raise Exception("Monitor is closed") @@ -193,15 +216,18 @@ class QEMUMachine(object): return events def event_wait(self, name, timeout=60.0, match=None): - # Test if 'match' is a recursive subset of 'event' - def event_match(event, match=None): + '''Wait for event in QMP, optionally filter results by match.''' + # Test if 'match' is a recursive subset of 'event'; skips branch + # processing on match's value `None` + # {"foo": {"bar": 1} matches {"foo": None} + def _event_match(event, match=None): if match is None: return True for key in match: if key in event: if isinstance(event[key], dict): - if not event_match(event[key], match[key]): + if not _event_match(event[key], match[key]): return False elif event[key] != match[key]: return False @@ -212,18 +238,22 @@ class QEMUMachine(object): # Search cached events for event in self._events: - if (event['event'] == name) and event_match(event, match): + if (event['event'] == name) and _event_match(event, match): self._events.remove(event) return event # Poll for new events while True: event = self._qmp.pull_event(wait=timeout) - if (event['event'] == name) and event_match(event, match): + if (event['event'] == name) and _event_match(event, match): return event self._events.append(event) return None def get_log(self): + ''' + After self.shutdown or failed qemu execution this returns the output + of the qemu process. + ''' return self._iolog -- 2.9.4