trace: avoid SystemTap dtrace(1) warnings on empty files

[mirror_qemu.git] / scripts / qmp / qom-set

#!/usr/bin/python
##
# QEMU Object Model test tools
#
# Copyright IBM, Corp. 2011
#
# Authors:
#  Anthony Liguori   <aliguori@us.ibm.com>
#
# This work is licensed under the terms of the GNU GPL, version 2 or later.  See
# the COPYING file in the top-level directory.
##

from __future__ import print_function
import sys
import os
from qmp import QEMUMonitorProtocol

cmd, args = sys.argv[0], sys.argv[1:]
socket_path = None
path = None
prop = None
value = None

def usage():
    return '''environment variables:
    QMP_SOCKET=<path | addr:port>
usage:
    %s [-h] [-s <QMP socket path | addr:port>] <path>.<property> <value>
''' % cmd

def usage_error(error_msg = "unspecified error"):
    sys.stderr.write('%s\nERROR: %s\n' % (usage(), error_msg))
    exit(1)

if len(args) > 0:
    if args[0] == "-h":
        print(usage())
        exit(0);
    elif args[0] == "-s":
        try:
            socket_path = args[1]
        except:
            usage_error("missing argument: QMP socket path or address");
        args = args[2:]

if not socket_path:
    if 'QMP_SOCKET' in os.environ:
        socket_path = os.environ['QMP_SOCKET']
    else:
        usage_error("no QMP socket path or address given");

if len(args) > 1:
    try:
        path, prop = args[0].rsplit('.', 1)
    except:
        usage_error("invalid format for path/property/value")
    value = args[1]
else:
    usage_error("not enough arguments")

srv = QEMUMonitorProtocol(socket_path)
srv.connect()

print(srv.command('qom-set', path=path, property=prop, value=value))