virt-manager/src/virtManager/connection.py

#
# Copyright (C) 2006 Red Hat, Inc.
# Copyright (C) 2006 Daniel P. Berrange <berrange@redhat.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
# MA 02110-1301 USA.
#

import gobject
import libvirt
import logging
import os, sys
import traceback
from time import time
from socket import gethostbyaddr, gethostname
import dbus
import threading
import gtk
import virtinst

from virtManager import util
from virtManager.domain import vmmDomain
from virtManager.network import vmmNetwork
from virtManager.storagepool import vmmStoragePool
from virtManager.interface import vmmInterface

XEN_SAVE_MAGIC = "LinuxGuestRecord"
QEMU_SAVE_MAGIC = "LibvirtQemudSave"
TEST_SAVE_MAGIC = "TestGuestMagic"

class vmmConnection(gobject.GObject):
    __gsignals__ = {
        "vm-added": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                     [str, str]),
        "vm-started": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                     [str, str]),
        "vm-removed": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                       [str, str]),

        "net-added": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                      [str, str]),
        "net-removed": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                        [str, str]),
        "net-started": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                        [str, str]),
        "net-stopped": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                        [str, str]),

        "pool-added": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                       [str, str]),
        "pool-removed": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                         [str, str]),
        "pool-started": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                         [str, str]),
        "pool-stopped": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                         [str, str]),

        "interface-added": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                            [str, str]),
        "interface-removed": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                              [str, str]),
        "interface-started": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                              [str, str]),
        "interface-stopped": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                              [str, str]),

        "resources-sampled": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                              []),
        "state-changed": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                          []),
        "connect-error": (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE,
                          [str]),
        }

    STATE_DISCONNECTED = 0
    STATE_CONNECTING = 1
    STATE_ACTIVE = 2
    STATE_INACTIVE = 3

    def __init__(self, config, uri, readOnly=None, netdev_helper=None):
        self.__gobject_init__()

        self.config = config
        self.netdev_helper = netdev_helper

        self.connectThread = None
        self.connectThreadEvent = threading.Event()
        self.connectThreadEvent.set()
        self.connectError = None
        self.uri = uri
        if self.uri is None or self.uri.lower() == "xen":
            self.uri = "xen:///"

        self.readOnly = readOnly
        self.state = self.STATE_DISCONNECTED
        self.vmm = None

        self.network_capable = None
        self.storage_capable = None
        self.interface_capable = None
        self.dom_xml_flags = None

        # Connection Storage pools: name -> vmmInterface
        self.interfaces = {}
        # Connection Storage pools: UUID -> vmmStoragePool
        self.pools = {}
        # Virtual networks UUUID -> vmmNetwork object
        self.nets = {}
        # Virtual machines. UUID -> vmmDomain object
        self.vms = {}
        # Running virtual machines. UUID -> vmmDomain object
        self.activeUUIDs = []
        # Resource utilization statistics
        self.record = []
        self.hostinfo = None
        self.autoconnect = self.config.get_conn_autoconnect(self.get_uri())

    def _acquire_tgt(self):
        logging.debug("In acquire tgt.")
        try:
            bus = dbus.SessionBus()
            ka = bus.get_object('org.gnome.KrbAuthDialog',
                                '/org/gnome/KrbAuthDialog')
            ret = ka.acquireTgt("", dbus_interface='org.gnome.KrbAuthDialog')
        except Exception, e:
            logging.info("Cannot acquire tgt" + str(e))
            ret = False
        return ret

    def is_read_only(self):
        return self.readOnly

    def is_active(self):
        return self.state == self.STATE_ACTIVE

    def get_type(self):
        if self.vmm is None:
            return None
        return self.vmm.getType()

    def is_local(self):
        return bool(self.get_uri_hostname() == "localhost")

    def get_qualified_hostname(self):
        if virtinst.support.check_conn_support(self.vmm,
                                virtinst.support.SUPPORT_CONN_GETHOSTNAME):
            return self.vmm.getHostname()

        uri_hostname = self.get_uri_hostname()
        if self.is_remote() and uri_hostname.lower() != "localhost":
            return uri_hostname

        # This can throw an exception, so beware when calling!
        return gethostbyaddr(gethostname())[0]

    def get_uri_hostname(self):
        return virtinst.util.get_uri_hostname(self.uri)

    def get_short_hostname(self):
        hostname = self.get_hostname()
        offset = hostname.find(".")
        if offset > 0 and not hostname[0].isdigit():
            return hostname[0:offset]
        return hostname

    def get_hostname(self, resolveLocal=False):
        try:
            return self.get_qualified_hostname()
        except:
            return self.get_uri_hostname()

    def get_transport(self):
        return virtinst.util.get_uri_transport(self.uri)

    def get_driver(self):
        return virtinst.util.get_uri_driver(self.uri)

    def get_capabilities(self):
        return virtinst.CapabilitiesParser.parse(self.vmm.getCapabilities())

    def set_dom_flags(self, vm):
        if self.dom_xml_flags != None:
            # Already set
            return

        self.dom_xml_flags = []
        for flags in [libvirt.VIR_DOMAIN_XML_SECURE,
                      libvirt.VIR_DOMAIN_XML_INACTIVE,
                      (libvirt.VIR_DOMAIN_XML_SECURE |
                       libvirt.VIR_DOMAIN_XML_INACTIVE )]:
            try:
                vm.XMLDesc(flags)
                self.dom_xml_flags.append(flags)
            except libvirt.libvirtError, e:
                logging.debug("%s does not support flags=%d : %s" %
                              (self.get_uri(), flags, str(e)))

    def has_dom_flags(self, flags):
        if self.dom_xml_flags == None:
            return False

        return bool(self.dom_xml_flags.count(flags))

    def is_xen(self):
        scheme = virtinst.util.uri_split(self.uri)[0]
        if scheme.startswith("xen"):
            return True
        return False

    def is_kvm_supported(self):
        if self.is_qemu_session():
            return False

        caps = self.get_capabilities()
        for guest in caps.guests:
            for dom in guest.domains:
                if dom.hypervisor_type == "kvm":
                    return True
        return False

    def is_remote(self):
        return virtinst.util.is_uri_remote(self.uri)

    def is_storage_capable(self):
        return virtinst.util.is_storage_capable(self.vmm)

    def is_nodedev_capable(self):
        return virtinst.NodeDeviceParser.is_nodedev_capable(self.vmm)

    def is_qemu_system(self):
        (scheme, ignore, ignore,
         path, ignore, ignore) = virtinst.util.uri_split(self.uri)
        if path == "/system" and scheme.startswith("qemu"):
            return True
        return False

    def is_qemu_session(self):
        (scheme, ignore, ignore,
         path, ignore, ignore) = virtinst.util.uri_split(self.uri)
        if path == "/session" and scheme.startswith("qemu"):
            return True
        return False

    def is_test_conn(self):
        (scheme, ignore, ignore,
         ignore, ignore, ignore) = virtinst.util.uri_split(self.uri)
        if scheme.startswith("test"):
            return True
        return False

    def _get_pretty_desc(self, active, shorthost):
        (scheme, ignore, hostname,
         path, ignore, ignore) = virtinst.util.uri_split(self.uri)

        hv = ""
        rest = ""
        scheme = scheme.split("+")[0]

        if hostname:
            if shorthost:
                rest = hostname.split(".")[0]
            else:
                rest = hostname
        else:
            rest = "localhost"

        if scheme == "qemu":
            hv = "QEMU"
            if active and self.is_kvm_supported():
                hv += "/KVM"
        else:
            hv = scheme.capitalize()

        if path and path != "/system":
            if path == "/session":
                hv += " Usermode"
            else:
                hv += " %s" % os.path.basename(path)

        return "%s (%s)" % (rest, hv)

    def get_pretty_desc_inactive(self, shorthost=True):
        return self._get_pretty_desc(False, shorthost)

    def get_pretty_desc_active(self, shorthost=True):
        return self._get_pretty_desc(True, shorthost)

    def get_uri(self):
        return self.uri

    def get_vm(self, uuid):
        return self.vms[uuid]

    def get_net(self, uuid):
        return self.nets[uuid]

    def get_net_by_name(self, name):
        for net in self.nets.values():
            if net.get_name() == name:
                return net

    def get_net_device(self, path):
        if not self.netdev_helper:
            raise ValueError("No netdev helper specified.")
        return self.netdev_helper.get_net_device(path)

    def get_pool(self, uuid):
        return self.pools[uuid]

    def get_interface(self, name):
        return self.interfaces[name]

    def get_devices(self, devtype=None, devcap=None):
        if not self.is_nodedev_capable():
            return []

        devs = self.vmm.listDevices(devtype, 0)
        retdevs = []

        for name in devs:
            dev = self.vmm.nodeDeviceLookupByName(name)
            vdev = virtinst.NodeDeviceParser.parse(dev.XMLDesc(0))

            if devcap and vdev.capability_type != devcap:
                continue

            retdevs.append(vdev)

        return retdevs

    def is_valid_saved_image(self, path):
        # FIXME: Not really sure why we are even doing this check? If libvirt
        # isn't exporting this information, seems like we shouldn't be duping
        # the validation. Maintain existing behavior until someone insists
        # otherwise I suppose.
        magic = ""

        # If running on PolKit or remote, we may not be able to access
        if not self.is_remote() and os.access(path, os.R_OK):
            try:
                f = open(path, "r")
                magic = f.read(16)
            except:
                logging.exception("Reading save image file header failed.")
                return False
        else:
            return True

        driver = self.get_driver()
        if driver == "xen" and not magic.startswith(XEN_SAVE_MAGIC):
            return False

        # Libvirt should validate the magic for other drivers
        return True


    def get_pool_by_path(self, path):
        for pool in self.pools.values():
            if pool.get_target_path() == path:
                return pool
        return None

    def get_pool_by_name(self, name):
        for p in self.pools.values():
            if p.get_name() == name:
                return p
        return None

    def get_vol_by_path(self, path):
        for pool in self.pools.values():
            for vol in pool.get_volumes().values():
                if vol.get_path() == path:
                    return vol
        return None

    def open(self):
        if self.state != self.STATE_DISCONNECTED:
            return

        self._change_state(self.STATE_CONNECTING)

        logging.debug("Scheduling background open thread for " + self.uri)
        self.connectThreadEvent.clear()
        self.connectThread = threading.Thread(target = self._open_thread,
                                              name = "Connect %s" % self.uri)
        self.connectThread.setDaemon(True)
        self.connectThread.start()

    def _do_creds_polkit(self, action):
        if os.getuid() == 0:
            logging.debug("Skipping policykit check as root")
            return 0
        logging.debug("Doing policykit for %s" % action)
        bus = dbus.SessionBus()

        try:
            # First try to use org.freedesktop.PolicyKit.AuthenticationAgent
            # which is introduced with PolicyKit-0.7
            obj = bus.get_object("org.freedesktop.PolicyKit.AuthenticationAgent", "/")
            pkit = dbus.Interface(obj, "org.freedesktop.PolicyKit.AuthenticationAgent")
            pkit.ObtainAuthorization(action, 0, os.getpid())
        except dbus.exceptions.DBusException, e:
            if e.get_dbus_name() != "org.freedesktop.DBus.Error.ServiceUnknown":
                raise e
            logging.debug("Falling back to org.gnome.PolicyKit")
            # If PolicyKit < 0.7, fallback to org.gnome.PolicyKit
            obj = bus.get_object("org.gnome.PolicyKit", "/org/gnome/PolicyKit/Manager")
            pkit = dbus.Interface(obj, "org.gnome.PolicyKit.Manager")
            pkit.ShowDialog(action, 0)
        return 0

    def _do_creds_dialog(self, creds):
        try:
            gtk.gdk.threads_enter()
            return self._do_creds_dialog_main(creds)
        finally:
            gtk.gdk.threads_leave()

    def _do_creds_dialog_main(self, creds):
        dialog = gtk.Dialog("Authentication required", None, 0, (gtk.STOCK_CANCEL, gtk.RESPONSE_CANCEL, gtk.STOCK_OK, gtk.RESPONSE_OK))
        label = []
        entry = []

        box = gtk.Table(2, len(creds))

        row = 0
        for cred in creds:
            if cred[0] == libvirt.VIR_CRED_AUTHNAME or cred[0] == libvirt.VIR_CRED_PASSPHRASE:
                label.append(gtk.Label(cred[1]))
            else:
                return -1

            ent = gtk.Entry()
            if cred[0] == libvirt.VIR_CRED_PASSPHRASE:
                ent.set_visibility(False)
            entry.append(ent)

            box.attach(label[row], 0, 1, row, row+1, 0, 0, 3, 3)
            box.attach(entry[row], 1, 2, row, row+1, 0, 0, 3, 3)
            row = row + 1

        vbox = dialog.get_child()
        vbox.add(box)

        dialog.show_all()
        res = dialog.run()
        dialog.hide()

        if res == gtk.RESPONSE_OK:
            row = 0
            for cred in creds:
                cred[4] = entry[row].get_text()
                row = row + 1
            dialog.destroy()
            return 0
        else:
            dialog.destroy()
            return -1

    def _do_creds(self, creds, cbdata):
        try:
            if (len(creds) == 1 and
                creds[0][0] == libvirt.VIR_CRED_EXTERNAL and
                creds[0][2] == "PolicyKit"):
                return self._do_creds_polkit(creds[0][1])

            for cred in creds:
                if cred[0] == libvirt.VIR_CRED_EXTERNAL:
                    return -1

            return self._do_creds_dialog(creds)
        except Exception, e:
            # Detailed error message, in English so it can be Googled.
            self.connectError = ("Failed to get credentials for '%s':\n%s\n%s"
                                 % (str(self.uri), str(e),
                                    "".join(traceback.format_exc())))
            logging.debug(self.connectError)
            return -1

    def _try_open(self):
        try:
            flags = 0
            if self.readOnly:
                logging.info("Caller requested read only connection")
                flags = libvirt.VIR_CONNECT_RO

            self.vmm = libvirt.openAuth(self.uri,
                                        [[libvirt.VIR_CRED_AUTHNAME,
                                          libvirt.VIR_CRED_PASSPHRASE,
                                          libvirt.VIR_CRED_EXTERNAL],
                                         self._do_creds,
                                         None], flags)
        except:
            return sys.exc_info()

    def _open_thread(self):
        logging.debug("Background thread is running")

        done = False
        while not done:
            open_error = self._try_open()
            done = True

            if not open_error:
                self.state = self.STATE_ACTIVE
            else:
                self.state = self.STATE_DISCONNECTED

                if self.uri.find("+ssh://") > 0:
                    hint = "\nMaybe you need to install ssh-askpass " + \
                           "in order to authenticate."
                else:
                    hint = ""

                (_type, value, stacktrace) = open_error

                if (type(_type) == type(libvirt.libvirtError) and
                    value.get_error_code() == libvirt.VIR_ERR_AUTH_FAILED and
                    "GSSAPI Error" in value.get_error_message() and
                    "No credentials cache found" in value.get_error_message()):
                    if self._acquire_tgt():
                        done = False
                        continue

                tb = "".join(traceback.format_exception(_type, value,
                                                        stacktrace))

                # Detailed error message, in English so it can be Googled.
                self.connectError = (("Unable to open connection to hypervisor"
                                      " URI '%s':\n%s\n%s"
                                      % (str(self.uri), value, tb + hint)))
                logging.error(self.connectError)


        # We want to kill off this thread asap, so schedule a gobject
        # idle even to inform the UI of result
        logging.debug("Background open thread complete, scheduling notify")
        gobject.idle_add(self._open_notify)
        self.connectThread = None

    def _open_notify(self):
        logging.debug("Notifying open result")

        try:
            gobject.idle_add(util.idle_emit, self, "state-changed")

            if self.state == self.STATE_ACTIVE:
                logging.debug("%s capabilities:\n%s" %
                              (self.get_uri(), self.vmm.getCapabilities()))

                self.tick()
                # If VMs disappeared since the last time we connected to
                # this uri, remove their gconf entries so we don't pollute
                # the database
                self.config.reconcile_vm_entries(self.get_uri(),
                                                 self.vms.keys())

            if self.state == self.STATE_DISCONNECTED:
                gobject.idle_add(util.idle_emit, self, "connect-error",
                                 self.connectError)
                self.connectError = None
        finally:
            self.connectThreadEvent.set()

    def _change_state(self, newstate):
        if self.state != newstate:
            self.state = newstate
            self.emit("state-changed")

    def pause(self):
        if self.state != self.STATE_ACTIVE:
            return
        self._change_state(self.STATE_INACTIVE)

    def resume(self):
        if self.state != self.STATE_INACTIVE:
            return
        self._change_state(self.STATE_ACTIVE)

    def close(self):
        if self.vmm == None:
            return

        #self.vmm.close()
        self.vmm = None
        self.nets = {}
        self.pools = {}
        self.vms = {}
        self.activeUUIDs = []
        self.record = []
        self._change_state(self.STATE_DISCONNECTED)

    def list_vm_uuids(self):
        return self.vms.keys()

    def list_net_uuids(self):
        return self.nets.keys()

    def list_net_device_paths(self):
        if not self.netdev_helper:
            return []
        if self.is_remote():
            return []
        return self.netdev_helper.list_net_device_paths()

    def list_pool_uuids(self):
        return self.pools.keys()

    def list_interface_names(self):
        return self.interfaces.keys()

    def get_host_info(self):
        return self.hostinfo

    def get_max_vcpus(self, _type=None):
        return virtinst.util.get_max_vcpus(self.vmm, _type)

    def get_autoconnect(self):
        # Use a local variable to cache autoconnect so we don't repeatedly
        # have to poll gconf
        return self.autoconnect

    def toggle_autoconnect(self):
        self.config.toggle_conn_autoconnect(self.get_uri())
        self.autoconnect = (not self.autoconnect)

    def connect(self, name, callback):
        handle_id = gobject.GObject.connect(self, name, callback)

        if name == "vm-added":
            for uuid in self.vms.keys():
                self.emit("vm-added", self.uri, uuid)

        return handle_id

    def pretty_host_memory_size(self):
        if self.vmm is None:
            return ""
        mem = self.host_memory_size()
        if mem > (10*1024*1024):
            return "%2.2f GB" % (mem/(1024.0*1024.0))
        else:
            return "%2.0f MB" % (mem/1024.0)


    def host_memory_size(self):
        if self.vmm is None:
            return 0
        return self.hostinfo[1]*1024

    def host_architecture(self):
        if self.vmm is None:
            return ""
        return self.hostinfo[0]

    def host_active_processor_count(self):
        if self.vmm is None:
            return 0
        return self.hostinfo[2]

    def host_maximum_processor_count(self):
        if self.vmm is None:
            return 0
        return self.hostinfo[4] * self.hostinfo[5] * self.hostinfo[6] * self.hostinfo[7]

    def create_network(self, xml, start=True, autostart=True):
        net = self.vmm.networkDefineXML(xml)
        uuid = self.uuidstr(net.UUID())
        self.nets[uuid] = vmmNetwork(self.config, self, net, uuid, False)
        self.nets[uuid].start()
        self.nets[uuid].set_active(True)
        self.nets[uuid].set_autostart(True)
        self.emit("net-added", self.uri, uuid)
        self.emit("net-started", self.uri, uuid)
        return self.nets[uuid]

    def define_domain(self, xml):
        self.vmm.defineXML(xml)

    def restore(self, frm):
        self.vmm.restore(frm)
        try:
            # FIXME: This isn't correct in the remote case. Why do we even
            #        do this? Seems like we should provide an option for this
            #        to the user.
            os.remove(frm)
        except:
            logging.debug("Couldn't remove save file '%s' used for restore." %
                          frm)

    def _update_nets(self):
        """
        Return lists of start/stopped/new networks
        """

        origNets = self.nets
        currentNets = {}
        startNets = []
        stopNets = []
        newNets = []
        newActiveNetNames = []
        newInactiveNetNames = []

        if self.network_capable == None:
            self.network_capable = virtinst.support.check_conn_support(
                                       self.vmm,
                                       virtinst.support.SUPPORT_CONN_NETWORK)
            if self.network_capable is False:
                logging.debug("Connection doesn't seem to support network "
                              "APIs. Skipping all network polling.")

        if not self.network_capable:
            return (stopNets, startNets, origNets, newNets, currentNets)

        try:
            newActiveNetNames = self.vmm.listNetworks()
        except:
            logging.exception("Unable to list active networks")
        try:
            newInactiveNetNames = self.vmm.listDefinedNetworks()
        except:
            logging.exception("Unable to list inactive networks")

        for name in newActiveNetNames:
            try:
                net = self.vmm.networkLookupByName(name)
                uuid = self.uuidstr(net.UUID())
                if not origNets.has_key(uuid):
                    # Brand new network
                    currentNets[uuid] = vmmNetwork(self.config, self, net,
                                                   uuid, True)
                    newNets.append(uuid)
                    startNets.append(uuid)
                else:
                    # Already present network, see if it changed state
                    currentNets[uuid] = origNets[uuid]
                    if not currentNets[uuid].is_active():
                        currentNets[uuid].set_active(True)
                        startNets.append(uuid)
                    del origNets[uuid]
            except libvirt.libvirtError:
                logging.exception("Couldn't fetch active network name '%s'" %
                                  name)

        for name in newInactiveNetNames:
            try:
                net = self.vmm.networkLookupByName(name)
                uuid = self.uuidstr(net.UUID())
                if not origNets.has_key(uuid):
                    currentNets[uuid] = vmmNetwork(self.config, self, net,
                                                 uuid, False)
                    newNets.append(uuid)
                else:
                    currentNets[uuid] = origNets[uuid]
                    if currentNets[uuid].is_active():
                        currentNets[uuid].set_active(False)
                        stopNets.append(uuid)
                    del origNets[uuid]
            except libvirt.libvirtError:
                logging.exception("Couldn't fetch inactive network name '%s'"
                                  % name)

        return (startNets, stopNets, newNets, origNets, currentNets)

    def _update_pools(self):
        origPools = self.pools
        currentPools = {}
        startPools = []
        stopPools = []
        newPools = []
        newActivePoolNames = []
        newInactivePoolNames = []

        if self.storage_capable == None:
            self.storage_capable = virtinst.util.is_storage_capable(self.vmm)
            if self.storage_capable is False:
                logging.debug("Connection doesn't seem to support storage "
                              "APIs. Skipping all storage polling.")

        if not self.storage_capable:
            return (stopPools, startPools, origPools, newPools, currentPools)

        try:
            newActivePoolNames = self.vmm.listStoragePools()
        except:
            logging.exception("Unable to list active pools")
        try:
            newInactivePoolNames = self.vmm.listDefinedStoragePools()
        except:
            logging.exception("Unable to list inactive pools")

        for name in newActivePoolNames:
            try:
                pool = self.vmm.storagePoolLookupByName(name)
                uuid = self.uuidstr(pool.UUID())
                if not origPools.has_key(uuid):
                    currentPools[uuid] = vmmStoragePool(self.config, self,
                                                        pool, uuid, True)
                    newPools.append(uuid)
                    startPools.append(uuid)
                else:
                    currentPools[uuid] = origPools[uuid]
                    if not currentPools[uuid].is_active():
                        currentPools[uuid].set_active(True)
                        startPools.append(uuid)
                    del origPools[uuid]
            except libvirt.libvirtError:
                logging.exception("Couldn't fetch active pool '%s'" % name)

        for name in newInactivePoolNames:
            try:
                pool = self.vmm.storagePoolLookupByName(name)
                uuid = self.uuidstr(pool.UUID())
                if not origPools.has_key(uuid):
                    currentPools[uuid] = vmmStoragePool(self.config, self,
                                                        pool, uuid, False)
                    newPools.append(uuid)
                else:
                    currentPools[uuid] = origPools[uuid]
                    if currentPools[uuid].is_active():
                        currentPools[uuid].set_active(False)
                        stopPools.append(uuid)
                    del origPools[uuid]
            except libvirt.libvirtError:
                logging.exception("Couldn't fetch inactive pool '%s'" % name)
        return (stopPools, startPools, origPools, newPools, currentPools)

    def _update_interfaces(self):
        orig = self.interfaces
        current = {}
        start = []
        stop = []
        new = []
        newActiveNames = []
        newInactiveNames = []

        if self.interface_capable == None:
            self.interface_capable = virtinst.support.check_conn_support(
                                       self.vmm,
                                       virtinst.support.SUPPORT_CONN_INTERFACE)
            if self.interface_capable is False:
                logging.debug("Connection doesn't seem to support interface "
                              "APIs. Skipping all interface polling.")

        if not self.interface_capable:
            return (stop, start, orig, new, current)

        try:
            newActiveNames = self.vmm.listInterfaces()
        except:
            logging.exception("Unable to list active interfaces")
        try:
            newInactiveNames = self.vmm.listDefinedInterfaces()
        except:
            logging.exception("Unable to list inactive interfaces")

        def check_obj(name, is_active):
            obj = self.vmm.interfaceLookupByName(name)
            key = obj.name()

            if not orig.has_key(key):
                # Object is brand new this tick period
                current[key] = vmmInterface(self.config, self, obj, key,
                                            is_active)
                new.append(key)

                if is_active:
                    start.append(key)
            else:
                # Previously known object, see if it changed state
                current[key] = orig[key]

                if current[key].is_active() != is_active:
                    current[key].set_active(is_active)

                    if is_active:
                        start.append(key)
                    else:
                        stop.append(key)

                del orig[key]

        for name in newActiveNames:
            try:
                check_obj(name, True)
            except libvirt.libvirtError:
                logging.exception("Couldn't fetch active "
                                  "interface '%s'" % name)

        for name in newInactiveNames:
            try:
                check_obj(name, False)
            except libvirt.libvirtError:
                logging.exception("Couldn't fetch inactive "
                                  "interface '%s'" % name)

        return (stop, start, orig, new, current)


    def _update_vms(self):
        """
        returns lists of changed VM states
        """

        oldActiveIDs = {}
        oldInactiveNames = {}
        for uuid in self.vms.keys():
            # first pull out all the current inactive VMs we know about
            vm = self.vms[uuid]
            if vm.get_id() == -1:
                oldInactiveNames[vm.get_name()] = vm
        for uuid in self.activeUUIDs:
            # Now get all the vms that were active the last time around
            # and are still active
            vm = self.vms[uuid]
            if vm.get_id() != -1:
                oldActiveIDs[vm.get_id()] = vm

        newActiveIDs = []
        try:
            newActiveIDs = self.vmm.listDomainsID()
        except:
            logging.exception("Unable to list active domains")

        newInactiveNames = []
        try:
            newInactiveNames = self.vmm.listDefinedDomains()
        except:
            logging.exception("Unable to list inactive domains")

        curUUIDs = {}       # new master list of vms
        maybeNewUUIDs = {}  # list of vms that changed state or are brand new
        oldUUIDs = {}       # no longer present vms
        newUUIDs = []       # brand new vms
        startedUUIDs = []   # previously present vms that are now running
        activeUUIDs = []    # all running vms

        # NB in these first 2 loops, we go to great pains to
        # avoid actually instantiating a new VM object so that
        # the common case of 'no new/old VMs' avoids hitting
        # XenD too much & thus slowing stuff down.

        # Filter out active domains which haven't changed
        if newActiveIDs != None:
            for _id in newActiveIDs:
                if oldActiveIDs.has_key(_id):
                    # No change, copy across existing VM object
                    vm = oldActiveIDs[_id]
                    curUUIDs[vm.get_uuid()] = vm
                    activeUUIDs.append(vm.get_uuid())
                else:
                    # May be a new VM, we have no choice but
                    # to create the wrapper so we can see
                    # if its a previously inactive domain.
                    try:
                        vm = self.vmm.lookupByID(_id)
                        uuid = self.uuidstr(vm.UUID())
                        maybeNewUUIDs[uuid] = vm
                        startedUUIDs.append(uuid)
                        activeUUIDs.append(uuid)
                    except libvirt.libvirtError:
                        logging.exception("Couldn't fetch domain id '%s'" %
                                          str(_id))

        # Filter out inactive domains which haven't changed
        if newInactiveNames != None:
            for name in newInactiveNames:
                if oldInactiveNames.has_key(name):
                    # No change, copy across existing VM object
                    vm = oldInactiveNames[name]
                    curUUIDs[vm.get_uuid()] = vm
                else:
                    # May be a new VM, we have no choice but
                    # to create the wrapper so we can see
                    # if its a previously inactive domain.
                    try:
                        vm = self.vmm.lookupByName(name)
                        uuid = self.uuidstr(vm.UUID())
                        maybeNewUUIDs[uuid] = vm
                    except libvirt.libvirtError:
                        logging.exception("Couldn't fetch domain id '%s'" %
                                          str(id))

        # At this point, maybeNewUUIDs has domains which are
        # either completely new, or changed state.

        # Filter out VMs which merely changed state, leaving
        # only new domains
        for uuid in maybeNewUUIDs.keys():
            rawvm = maybeNewUUIDs[uuid]
            if not(self.vms.has_key(uuid)):
                vm = vmmDomain(self.config, self, rawvm, uuid)
                newUUIDs.append(uuid)
                curUUIDs[uuid] = vm
            else:
                vm = self.vms[uuid]
                vm.release_handle()
                vm.set_handle(rawvm)
                curUUIDs[uuid] = vm

        # Finalize list of domains which went away altogether
        for uuid in self.vms.keys():
            vm = self.vms[uuid]
            if not(curUUIDs.has_key(uuid)):
                oldUUIDs[uuid] = vm

        return (startedUUIDs, newUUIDs, oldUUIDs, curUUIDs, activeUUIDs)

    def tick(self, noStatsUpdate=False):
        """ main update function: polls for new objects, updates stats, ..."""
        if self.state != self.STATE_ACTIVE:
            return

        self.hostinfo = self.vmm.getInfo()

        # Poll for new virtual network objects
        (startNets, stopNets, newNets,
         oldNets, self.nets) = self._update_nets()

        # Update pools
        (stopPools, startPools, oldPools,
         newPools, self.pools) = self._update_pools()

        # Update interfaces
        (stopInterfaces, startInterfaces, oldInterfaces,
         newInterfaces, self.interfaces) = self._update_interfaces()

        # Poll for changed/new/removed VMs
        (startVMs, newVMs, oldVMs,
         self.vms, self.activeUUIDs) = self._update_vms()

        def tick_send_signals():
            """
            Responsible for signaling the UI for any updates. All possible UI
            updates need to go here to enable threading that doesn't block the
            app with long tick operations.
            """

            # Update VM states
            for uuid in oldVMs:
                self.emit("vm-removed", self.uri, uuid)
                oldVMs[uuid].release_handle()
            for uuid in newVMs:
                self.emit("vm-added", self.uri, uuid)
            for uuid in startVMs:
                self.emit("vm-started", self.uri, uuid)

            # Update virtual network states
            for uuid in oldNets:
                self.emit("net-removed", self.uri, uuid)
            for uuid in newNets:
                self.emit("net-added", self.uri, uuid)
            for uuid in startNets:
                self.emit("net-started", self.uri, uuid)
            for uuid in stopNets:
                self.emit("net-stopped", self.uri, uuid)

            # Update storage pool states
            for uuid in oldPools:
                self.emit("pool-removed", self.uri, uuid)
            for uuid in newPools:
                self.emit("pool-added", self.uri, uuid)
            for uuid in startPools:
                self.emit("pool-started", self.uri, uuid)
            for uuid in stopPools:
                self.emit("pool-stopped", self.uri, uuid)

            # Update interface states
            for name in oldInterfaces:
                self.emit("interface-removed", self.uri, name)
            for name in newInterfaces:
                self.emit("interface-added", self.uri, name)
            for name in startInterfaces:
                self.emit("interface-started", self.uri, name)
            for name in stopInterfaces:
                self.emit("interface-stopped", self.uri, name)


        gobject.idle_add(tick_send_signals)

        # Finally, we sample each domain
        now = time()

        updateVMs = self.vms
        if noStatsUpdate:
            updateVMs = newVMs

        for uuid in updateVMs:
            vm = self.vms[uuid]
            try:
                vm.tick(now)
            except libvirt.libvirtError, e:
                if e.get_error_code() == libvirt.VIR_ERR_SYSTEM_ERROR:
                    raise
                logging.exception("Tick for VM '%s' failed" % vm.get_name())
            except Exception, e:
                logging.exception("Tick for VM '%s' failed" % vm.get_name())

        if not noStatsUpdate:
            self._recalculate_stats(now)

            gobject.idle_add(util.idle_emit, self, "resources-sampled")

        return 1

    def _recalculate_stats(self, now):
        expected = self.config.get_stats_history_length()
        current = len(self.record)
        if current > expected:
            del self.record[expected:current]

        mem = 0
        cpuTime = 0
        rdRate = 0
        wrRate = 0
        rxRate = 0
        txRate = 0

        for uuid in self.vms:
            vm = self.vms[uuid]
            if vm.get_id() != -1:
                cpuTime = cpuTime + vm.cpu_time()
                mem = mem + vm.get_memory()
                rdRate += vm.disk_read_rate()
                wrRate += vm.disk_write_rate()
                rxRate += vm.network_rx_rate()
                txRate += vm.network_tx_rate()

        pcentCpuTime = 0
        if len(self.record) > 0:
            prevTimestamp = self.record[0]["timestamp"]

            pcentCpuTime = (cpuTime) * 100.0 / ((now - prevTimestamp)*1000.0*1000.0*1000.0*self.host_active_processor_count())
            # Due to timing diffs between getting wall time & getting
            # the domain's time, its possible to go a tiny bit over
            # 100% utilization. This freaks out users of the data, so
            # we hard limit it.
            if pcentCpuTime > 100.0:
                pcentCpuTime = 100.0
            # Enforce >= 0 just in case
            if pcentCpuTime < 0.0:
                pcentCpuTime = 0.0

        pcentMem = mem * 100.0 / self.host_memory_size()

        newStats = {
            "timestamp": now,
            "memory": mem,
            "memoryPercent": pcentMem,
            "cpuTime": cpuTime,
            "cpuTimePercent": pcentCpuTime,
            "diskRdRate" : rdRate,
            "diskWrRate" : wrRate,
            "netRxRate" : rxRate,
            "netTxRate" : txRate,
        }

        self.record.insert(0, newStats)

    def cpu_time_vector(self):
        vector = []
        stats = self.record
        for i in range(self.config.get_stats_history_length()+1):
            if i < len(stats):
                vector.append(stats[i]["cpuTimePercent"]/100.0)
            else:
                vector.append(0)
        return vector

    def cpu_time_vector_limit(self, limit):
        cpudata = self.cpu_time_vector()
        if len(cpudata) > limit:
            cpudata = cpudata[0:limit]
        return cpudata

    def cpu_time_percentage(self):
        if len(self.record) == 0:
            return 0
        return self.record[0]["cpuTimePercent"]

    def current_memory(self):
        if len(self.record) == 0:
            return 0
        return self.record[0]["memory"]

    def pretty_current_memory(self):
        mem = self.current_memory()
        if mem > (10*1024*1024):
            return "%2.2f GB" % (mem/(1024.0*1024.0))
        else:
            return "%2.0f MB" % (mem/1024.0)

    def current_memory_percentage(self):
        if len(self.record) == 0:
            return 0
        return self.record[0]["memoryPercent"]

    def current_memory_vector(self):
        vector = []
        stats = self.record
        for i in range(self.config.get_stats_history_length()+1):
            if i < len(stats):
                vector.append(stats[i]["memoryPercent"]/100.0)
            else:
                vector.append(0)
        return vector

    def network_rx_rate(self):
        if len(self.record) == 0:
            return 0
        return self.record[0]["netRxRate"]

    def network_tx_rate(self):
        if len(self.record) == 0:
            return 0
        return self.record[0]["netTxRate"]

    def network_traffic_rate(self):
        return self.network_tx_rate() + self.network_rx_rate()

    def disk_read_rate(self):
        if len(self.record) == 0:
            return 0
        return self.record[0]["diskRdRate"]

    def disk_write_rate(self):
        if len(self.record) == 0:
            return 0
        return self.record[0]["diskWrRate"]

    def disk_io_rate(self):
        return self.disk_read_rate() + self.disk_write_rate()
       
    def disk_io_vector_limit(self, dummy):
        """No point to accumulate unnormalized I/O for a conenction"""
        return [ 0.0 ]

    def network_traffic_vector_limit(self, dummy):
        """No point to accumulate unnormalized Rx/Tx for a conenction"""
        return [ 0.0 ]

    def uuidstr(self, rawuuid):
        hx = ['0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f']
        uuid = []
        for i in range(16):
            uuid.append(hx[((ord(rawuuid[i]) >> 4) & 0xf)])
            uuid.append(hx[(ord(rawuuid[i]) & 0xf)])
            if i == 3 or i == 5 or i == 7 or i == 9:
                uuid.append('-')
        return "".join(uuid)

    def get_state(self):
        return self.state

    def get_state_text(self):
        if self.state == self.STATE_DISCONNECTED:
            return _("Disconnected")
        elif self.state == self.STATE_CONNECTING:
            return _("Connecting")
        elif self.state == self.STATE_ACTIVE:
            if self.is_read_only():
                return _("Active (RO)")
            else:
                return _("Active")
        elif self.state == self.STATE_INACTIVE:
            return _("Inactive")
        else:
            return _("Unknown")

    # Per-Connection preferences
    def config_add_iso_path(self, path):
        self.config.set_perhost(self.get_uri(), self.config.add_iso_path, path)
    def config_get_iso_paths(self):
        return self.config.get_perhost(self.get_uri(),
                                       self.config.get_iso_paths)

gobject.type_register(vmmConnection)