'''
Netlink message generation/parsing
Copyright 2007 Johannes Berg <johannes@sipsolutions.net>
GPLv2+; See copying for details.
'''
import struct
from iotop.netlink import NLM_F_REQUEST, NLMSG_MIN_TYPE, Message, parse_attributes
from iotop.netlink import NulStrAttr, Connection, NETLINK_GENERIC
CTRL_CMD_UNSPEC = 0
CTRL_CMD_NEWFAMILY = 1
CTRL_CMD_DELFAMILY = 2
CTRL_CMD_GETFAMILY = 3
CTRL_CMD_NEWOPS = 4
CTRL_CMD_DELOPS = 5
CTRL_CMD_GETOPS = 6
CTRL_ATTR_UNSPEC = 0
CTRL_ATTR_FAMILY_ID = 1
CTRL_ATTR_FAMILY_NAME = 2
CTRL_ATTR_VERSION = 3
CTRL_ATTR_HDRSIZE = 4
CTRL_ATTR_MAXATTR = 5
CTRL_ATTR_OPS = 6
class GenlHdr:
def __init__(self, cmd, version = 0):
self.cmd = cmd
self.version = version
def _dump(self):
return struct.pack("BBxx", self.cmd, self.version)
def _genl_hdr_parse(data):
return GenlHdr(*struct.unpack("BBxx", data))
GENL_ID_CTRL = NLMSG_MIN_TYPE
class GeNlMessage(Message):
def __init__(self, family, cmd, attrs=[], flags=0):
self.cmd = cmd
self.attrs = attrs
self.family = family
Message.__init__(self, family, flags=flags,
payload=[GenlHdr(self.cmd)]+attrs)
@staticmethod
def recv(conn):
msg = conn.recv()
packet = msg.payload
hdr = _genl_hdr_parse(packet[:4])
genlmsg = GeNlMessage(msg.type, hdr.cmd, [], msg.flags)
genlmsg.attrs = parse_attributes(packet[4:])
genlmsg.version = hdr.version
return genlmsg
class Controller:
def __init__(self, conn):
self.conn = conn
def get_family_id(self, family):
a = NulStrAttr(CTRL_ATTR_FAMILY_NAME, family)
m = GeNlMessage(GENL_ID_CTRL, CTRL_CMD_GETFAMILY,
flags=NLM_F_REQUEST, attrs=[a])
m.send(self.conn)
m = GeNlMessage.recv(self.conn)
return m.attrs[CTRL_ATTR_FAMILY_ID].u16()
connection = Connection(NETLINK_GENERIC)
controller = Controller(connection)