Even with -Wuninitialized (which is part of autobuild.sh
--enable-compile-warnings=error), gcc does NOT catch this
use of an uninitialized variable:
{
if (cond)
goto error;
int a = 1;
error:
printf("%d", a);
}
which prints 0 (supposing the stack started life wiped) if
cond was true. Clang will catch it, but we don't use clang
as often. Using gcc -Wjump-misses-init catches it, but also
gives false positives:
{
if (cond)
goto error;
int a = 1;
return a;
error:
return 0;
}
Here, a was never used in the scope of the error block, so
declaring it after goto is technically fine (and clang agrees).
However, given that our HACKING already documents a preference
to C89 decl-before-statement, the false positive warning is
enough of a prod to comply with HACKING.
[Personally, I'd _really_ rather use C99 decl-after-statement
to minimize scope, but until gcc can efficiently and reliably
catch scoping and uninitialized usage bugs, I'll settle with
the compromise of enforcing a coding standard that happens to
reject false positives if it can also detect real bugs.]
* acinclude.m4 (LIBVIRT_COMPILE_WARNINGS): Add -Wjump-misses-init.
* src/util/util.c (__virExec): Adjust offenders.
* src/conf/domain_conf.c (virDomainTimerDefParseXML): Likewise.
* src/remote/remote_driver.c (doRemoteOpen): Likewise.
* src/phyp/phyp_driver.c (phypGetLparNAME, phypGetLparProfile)
(phypGetVIOSFreeSCSIAdapter, phypVolumeGetKey)
(phypGetStoragePoolDevice)
(phypVolumeGetPhysicalVolumeByStoragePool)
(phypVolumeGetPath): Likewise.
* src/vbox/vbox_tmpl.c (vboxNetworkUndefineDestroy)
(vboxNetworkCreate, vboxNetworkDumpXML)
(vboxNetworkDefineCreateXML): Likewise.
* src/xenapi/xenapi_driver.c (getCapsObject)
(xenapiDomainDumpXML): Likewise.
* src/xenapi/xenapi_utils.c (createVMRecordFromXml): Likewise.
* src/security/security_selinux.c (SELinuxGenNewContext):
Likewise.
* src/qemu/qemu_command.c (qemuBuildCommandLine): Likewise.
* src/qemu/qemu_hotplug.c (qemuDomainChangeEjectableMedia):
Likewise.
* src/qemu/qemu_process.c (qemuProcessWaitForMonitor): Likewise.
* src/qemu/qemu_monitor_text.c (qemuMonitorTextGetPtyPaths):
Likewise.
* src/qemu/qemu_driver.c (qemudDomainShutdown)
(qemudDomainBlockStats, qemudDomainMemoryPeek): Likewise.
* src/storage/storage_backend_iscsi.c
(virStorageBackendCreateIfaceIQN): Likewise.
* src/node_device/node_device_udev.c (udevProcessPCI): Likewise.
Implementations of following functions:
virDomainVcpupinIsDuplicate
virDomainVcpupinFindByVcpu
virDomainVcpupinAdd
Update "virDomainDefParseXML" to parse, and "virDomainDefFormatXML"
to build cputune xml, also implementations of new internal helper
functions.
v1 - v2:
* Resolve potential crash bug of "virDomainVcpupinAdd"
Also related new functions' declaration, and expose the new introduced
functions in libvirt_private.syms.
v1 - v2:
Don't expose "virAllocVar" in libvirt_private.syms
Add the compiler attribute to ensure we don't introduce any more
ref bugs like were just patched in commit 9741f34, then explicitly
mark the remaining places in code that are safe.
* src/qemu/qemu_monitor.h (qemuMonitorUnref): Mark
ATTRIBUTE_RETURN_CHECK.
* src/conf/domain_conf.h (virDomainObjUnref): Likewise.
* src/conf/domain_conf.c (virDomainObjParseXML)
(virDomainLoadStatus): Fix offenders.
* src/openvz/openvz_conf.c (openvzLoadDomains): Likewise.
* src/vmware/vmware_conf.c (vmwareLoadDomains): Likewise.
* src/qemu/qemu_domain.c (qemuDomainObjBeginJob)
(qemuDomainObjBeginJobWithDriver)
(qemuDomainObjExitRemoteWithDriver): Likewise.
* src/qemu/qemu_monitor.c (QEMU_MONITOR_CALLBACK): Likewise.
Suggested by Daniel P. Berrange.
The ref count was assigned to 1 at creation, then never modified again
until it was decremented just before freeing the object.
* src/conf/domain_conf.h (_virDomainSnapshotObj): Delete unused
field.
(virDomainSnapshotObjUnref): Delete unused prototype.
* src/libvirt_private.syms: Likewise.
* src/conf/domain_conf.c (virDomainSnapshotObjNew)
(virDomainSnapshotObjListDataFree): Update users.
(virDomainSnapshotObjUnref): Delete.
If pool xml has no definition for "port", then "Segmentation fault"
happens when jumping to "cleanup:" to do "VIR_FREE(port)", as "port"
was not initialized in this situation.
* src/conf/storage_conf.c
For qemu names the primary vga as "qxl-vga":
1) if vram is specified for 2nd qxl device:
-vga qxl -global qxl-vga.vram_size=$SIZE \
-device qxl,id=video1,vram_size=$SIZE,...
2) if vram is not specified for 2nd qxl device, (use the default
set by global):
-vga qxl -global qxl-vga.vram_size=$SIZE \
-device qxl,id=video1,...
For qemu names all qxl devices as "qxl":
1) if vram is specified for 2nd qxl device:
-vga qxl -global qxl.vram_size=$SIZE \
-device qxl,id=video1,vram_size=$SIZE ...
2) if vram is not specified for 2nd qxl device:
-vga qxl -global qxl-vga.vram_size=$SIZE \
-device qxl,id=video1,...
"-global" is the only way to define vram_size for the primary qxl
device, regardless of how qemu names it, (It's not good a good
way, as original idea of "-global" is to set a global default for
a driver property, but to specify vram for first qxl device, we
have to use it).
For other qxl devices, as they are represented by "-device", could
specify it directly and seperately for each, and it overrides the
default set by "-global" if specified.
v1 - v2:
* modify "virDomainVideoDefaultRAM" so that it returns 16M as the
default vram_size for qxl device.
* vram_size * 1024 (qemu accepts bytes for vram_size).
* apply default vram_size for qxl device for which vram_size is
not specified.
* modify "graphics-spice" tests (more sensiable vram_size)
* Add an argument of virDomainDefPtr type for qemuBuildVideoDevStr,
to use virDomainVideoDefaultRAM in qemuBuildVideoDevStr).
v2 - v3:
* Modify default video memory size for qxl device from 16M to 24M
* Update codes to be consistent with changes on qemu_capabilities.*
this is the patch to fix the virDomainChrDefParseTargetXML() functionality
to parse the target port from XML if available. This is necessary for
multiple serial port support which is the second part of this patch.
Signed-off-by: Michal Novotny <minovotn@redhat.com>
Relax the restriction that the hash table key must be a string
by allowing an arbitrary hash code generator + comparison func
to be provided
* util/hash.c, util/hash.h: Allow any pointer as a key
* internal.h: Include stdbool.h as standard.
* conf/domain_conf.c, conf/domain_conf.c,
conf/nwfilter_params.c, nwfilter/nwfilter_gentech_driver.c,
nwfilter/nwfilter_gentech_driver.h, nwfilter/nwfilter_learnipaddr.c,
qemu/qemu_command.c, qemu/qemu_driver.c,
qemu/qemu_process.c, uml/uml_driver.c,
xen/xm_internal.c: s/char */void */ in hash callbacks
Since the deallocator is passed into the constructor of
a hash table it is not desirable to pass it into each
function again. Remove it from all functions, but provide
a virHashSteal to allow a item to be removed from a hash
table without deleteing it.
* src/util/hash.c, src/util/hash.h: Remove deallocator
param from all functions. Add virHashSteal
* src/libvirt_private.syms: Add virHashSteal
* src/conf/domain_conf.c, src/conf/nwfilter_params.c,
src/nwfilter/nwfilter_learnipaddr.c,
src/qemu/qemu_command.c, src/xen/xm_internal.c: Update
for changed hash API
This patch adds the possibility to not just drop packets, but to also have them rejected where iptables at least sends an ICMP msg back to the originator. On ebtables this again maps into dropping packets since rejecting is not supported.
I am adding 'since 0.8.9' to the docs assuming this will be the next version of libvirt.
Now that the virHash handling functions call virReportOOMError by
themselves when needed, users of the virHash API no longer need to
do it by themselves. Since users of the virHash API were not
consistently calling virReportOOMError after memory failures from
the virHash code, this has the added benefit of making OOM
reporting from this code more consistent and reliable.
This fixes https://bugzilla.redhat.com/show_bug.cgi?id=609463
The problem was that, since a bridge always acquires the MAC address
of the connected interface with the numerically lowest MAC, as guests
are started and stopped, it was possible for the MAC address to change
over time, and this change in the network was being detected by
Windows 7 (it sees the MAC of the default route change), so on each
reboot it would bring up a dialog box asking about this "new network".
The solution is to create a dummy tap interface with a MAC guaranteed
to be lower than any guest interface's MAC, and attach that tap to the
bridge as soon as it's created. Since all guest MAC addresses start
with 0xFE, we can just generate a MAC with the standard "0x52, 0x54,
0" prefix, and it's guaranteed to always win (physical interfaces are
never connected to these bridges, so we don't need to worry about
competing numerically with them).
Note that the dummy tap is never set to IFF_UP state - that's not
necessary in order for the bridge to take its MAC, and not setting it
to UP eliminates the clutter of having an (eg) "virbr0-nic" displayed
in the output of the ifconfig command.
I chose to not auto-generate the MAC address in the network XML
parser, as there are likely to be consumers of that API that don't
need or want to have a MAC address associated with the
bridge.
Instead, in bridge_driver.c when the network is being defined, if
there is no MAC, one is generated. To account for virtual network
configs that already exist when upgrading from an older version of
libvirt, I've added a %post script to the specfile that searches for
all network definitions in both the config directory
(/etc/libvirt/qemu/networks) and the state directory
(/var/lib/libvirt/network) that are missing a mac address, generates a
random address, and adds it to the config (and a matching address to
the state file, if there is one).
docs/formatnetwork.html.in: document <mac address.../>
docs/schemas/network.rng: add nac address to schema
libvirt.spec.in: %post script to update existing networks
src/conf/network_conf.[ch]: parse and format <mac address.../>
src/libvirt_private.syms: export a couple private symbols we need
src/network/bridge_driver.c:
auto-generate mac address when needed,
create dummy interface if mac address is present.
tests/networkxml2xmlin/isolated-network.xml
tests/networkxml2xmlin/routed-network.xml
tests/networkxml2xmlout/isolated-network.xml
tests/networkxml2xmlout/routed-network.xml: add mac address to some tests
This is in response to:
https://bugzilla.redhat.com/show_bug.cgi?id=629662
Explanation
qemu's virtio-net-pci driver allows setting the algorithm used for tx
packets to either "bh" or "timer". This is done by adding ",tx=bh" or
",tx=timer" to the "-device virtio-net-pci" commandline option.
'bh' stands for 'bottom half'; when this is set, packet tx is all done
in an iothread in the bottom half of the driver. (In libvirt, this
option is called the more descriptive "iothread".)
'timer' means that tx work is done in qemu, and if there is more tx
data than can be sent at the present time, a timer is set before qemu
moves on to do other things; when the timer fires, another attempt is
made to send more data. (libvirt retains the name "timer" for this
option.)
The resulting difference, according to the qemu developer who added
the option is:
bh makes tx more asynchronous and reduces latency, but potentially
causes more processor bandwidth contention since the cpu doing the
tx isn't necessarily the cpu where the guest generated the
packets.
Solution
This patch provides a libvirt domain xml knob to change the option on
the qemu commandline, by adding a new attribute "txmode" to the
<driver> element that can be placed inside any <interface> element in
a domain definition. It's use would be something like this:
<interface ...>
...
<model type='virtio'/>
<driver txmode='iothread'/>
...
</interface>
I chose to put this setting as an attribute to <driver> rather than as
a sub-element to <tune> because it is specific to the virtio-net
driver, not something that is generally usable by all network drivers.
(note that this is the same placement as the "driver name=..."
attribute used to choose kernel vs. userland backend for the
virtio-net driver.)
Actually adding the tx=xxx option to the qemu commandline is only done
if the version of qemu being used advertises it in the output of
qemu -device virtio-net-pci,?
If a particular txmode is requested in the XML, and the option isn't
listed in that help output, an UNSUPPORTED_CONFIG error is logged, and
the domain fails to start.
When the <driver> element (and its "name" attribute) was added to the
domain XML's interface element, a "backend" enum was simply added to
the toplevel of the virDomainNetDef struct.
Ignoring the naming inconsistency ("name" vs. "backend"), this is fine
when there's only a single item contained in the driver element of the
XML, but doesn't scale well as we add more attributes that apply to
the backend of the virtio-net driver, or add attributes applicable to
other drivers.
This patch changes virDomainNetDef in two ways:
1) Rename the item in the struct from "backend" to "name", so that
it's the same in the XML and in the struct, hopefully avoiding
confusion for someone unfamiliar with the function of the
attribute.
2) Create a "driver" union within virDomainNetDef, and a "virtio"
struct in that struct, which contains the "name" enum value.
3) Move around the virDomainNetParse and virDomainNetFormat functions
to allow for simple plugin of new attributes without disturbing
existing code. (you'll note that this results in a seemingly
redundant if() in the format function, but that will no longer be
the case as soon as a 2nd attribute is added).
In the future, new attributes for the virtio driver backend can be
added to the "virtio" struct, and any other network device backend that
needs an attribute will have its own struct added to the "driver"
union.
When formatting XML for smartcard device with mode=host, libvirt
generates invalid XML if the device has address info associated:
<smartcard mode='host' <address type='ccid' controller='0' slot='1'/>
When run non-root the nwfilter driver logs error messages about
being unable to find iptables/ebtables commands (they are in
/sbin which isn't in $PATH). The nwfilter driver can't ever work
as non-root, so simply skip it entirely thus avoiding the error
messages
* src/conf/nwfilter_conf.h, src/nwfilter/nwfilter_driver.c,
src/nwfilter/nwfilter_gentech_driver.c,
src/nwfilter/nwfilter_gentech_driver.h: Pass 'bool privileged'
flag down to final driver impl
* src/nwfilter/nwfilter_ebiptables_driver.c: Skip initialization
if not privileged
A typo s/spice/vnc/ caused parsing of the spice 'auth' data
to write into the wrong part of the struct, blowing away
other unrelated data.
* src/conf/domain_conf.c: s/vnc/spice/ in parsing spice auth
Adds <smartcard mode='passthrough' type='spicevmc'/>, which uses the
new <channel name='smartcard'/> of <graphics type='spice'>.
* docs/schemas/domain.rng: Support new XML.
* docs/formatdomain.html.in: Document it.
* src/conf/domain_conf.h (virDomainGraphicsSpiceChannelName): New
enum value.
(virDomainChrSpicevmcName): New enum.
(virDomainChrSourceDef): Distinguish spicevmc types.
* src/conf/domain_conf.c (virDomainGraphicsSpiceChannelName): Add
smartcard.
(virDomainSmartcardDefParseXML): Parse it.
(virDomainChrDefParseXML, virDomainSmartcardDefParseXML): Set
spicevmc name.
(virDomainChrSpicevmc): New enum conversion functions.
* src/libvirt_private.syms: Export new functions.
* src/qemu/qemu_command.c (qemuBuildChrChardevStr): Conditionalize
name.
* tests/qemuxml2argvtest.c (domain): New test.
* tests/qemuxml2argvdata/qemuxml2argv-smartcard-passthrough-spicevmc.args:
New file.
* tests/qemuxml2argvdata/qemuxml2argv-smartcard-passthrough-spicevmc.xml:
Likewise.
Inspired by https://bugzilla.redhat.com/show_bug.cgi?id=615757
Add a new character device backend for virtio serial channels that
activates the QEMU spice agent on the main channel using the vdagent
spicevmc connection. The <target> must be type='virtio', and supports
an optional name that specifies how the guest will see the channel
(for now, name must be com.redhat.spice.0).
<channel type='spicevmc'>
<target type='virtio'/>
<address type='virtio-serial' controller='1' bus='0' port='3'/>
</channel>
* docs/schemas/domain.rng: Support new XML.
* docs/formatdomain.html.in: Document it.
* src/conf/domain_conf.h (virDomainChrType): New enum value.
* src/conf/domain_conf.c (virDomainChr): Add spicevmc.
(virDomainChrDefParseXML, virDomainChrSourceDefParseXML)
(virDomainChrDefParseTargetXML): Parse and enforce proper use.
(virDomainChrSourceDefFormat, virDomainChrDefFormat): Format.
* src/qemu/qemu_command.c (qemuBuildChrChardevStr)
(qemuBuildCommandLine): Add qemu support.
* tests/qemuxml2argvtest.c (domain): New test.
* tests/qemuxml2argvdata/qemuxml2argv-channel-spicevmc.xml: New
file.
* tests/qemuxml2argvdata/qemuxml2argv-channel-spicevmc.args:
Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
* src/conf/domain_conf.h (virDomainSmartcardType): New enum.
(virDomainSmartcardDef, virDomainDeviceCcidAddress): New structs.
(virDomainDef): Include smartcards.
(virDomainSmartcardDefIterator): New typedef.
(virDomainSmartcardDefFree, virDomainSmartcardDefForeach): New
prototypes.
(virDomainControllerType, virDomainDeviceAddressType): Add ccid
enum values.
(virDomainDeviceInfo): Add ccid address type.
* src/conf/domain_conf.c (virDomainSmartcard): Convert between
enum and string.
(virDomainSmartcardDefParseXML, virDomainSmartcardDefFormat)
(virDomainSmartcardDefFree, virDomainDeviceCcidAddressParseXML)
(virDomainDefMaybeAddSmartcardController): New functions.
(virDomainDefParseXML): Parse the new XML.
(virDomainDefFormat): Convert back to XML.
(virDomainDefFree): Clean up.
(virDomainDeviceInfoIterate): Iterate over passthrough aliases.
(virDomainController, virDomainDeviceAddress)
(virDomainDeviceInfoParseXML, virDomainDeviceInfoFormat)
(virDomainDefAddImplicitControllers): Support new values.
* src/libvirt_private.syms (domain_conf.h): New exports.
* cfg.mk (useless_free_options): List new function.
In QEMU, the card itself is a PCI device, but it requires a codec
(either -device hda-output or -device hda-duplex) to actually output
sound. Specifying <sound model='ich6'/> gives us -device intel-hda
-device hda-duplex I think it's important that a simple <sound model='ich6'/>
sets up a useful codec, to have consistent behavior with all other sound cards.
This is basically Dan's proposal of
<sound model='ich6'>
<codec type='output' slot='0'/>
<codec type='duplex' slot='3'/>
</sound>
without the codec bits implemented.
The important thing is to keep a consistent API here, we don't want some
<sound> devs require tweaking codecs but not others. Steps I see to
accomplishing this:
- every <sound> device has a <codec type='default'/> (unless codecs are
manually specified)
- <codec type='none'/> is required to specify 'no codecs'
- new audio settings like mic=on|off could then be exposed in
<sound> or <codec> in a consistent manner for all sound models
v2:
Use model='ich6'
v3:
Use feature detection, from eblake
Set codec id, bus, and cad values
v4:
intel-hda isn't supported if -device isn't available
v5:
Comment spelling fixes
QEMU supports serving VNC over a unix domain socket rather than traditional
TCP host/port. This is specified with:
<graphics type='vnc' socket='/foo/bar/baz'/>
This provides better security access control than VNC listening on
127.0.0.1, but will cause issues with tools that rely on the lax security
(virt-manager in fedora runs as regular user by default, and wouldn't be
able to access a socket owned by 'qemu' or 'root').
Also not currently supported by any clients, though I have patches for
virt-manager, and virt-viewer should be simple to update.
v2:
schema: Make listen vs. socket a <choice>
This will allow us to record transient runtime state in vm->def, like
default VNC parameters. Accomplish this by adding an extra 'live' parameter
to SetDefTransient, with similar semantics to the 'live' flag for
AssignDef.
The public object is called NWFilter but the corresponding private
object is called NWFilterPool. I don't see compelling reasons for this
Pool suffix. One might argue that an NWFilter is a "pool" of rules, etc.
Remove the Pool suffix from NWFilterPool. No functional change included.
Currently, boot order can be specified per device class but there is no
way to specify exact disk/NIC device to boot from.
This patch adds <boot order='N'/> element which can be used inside
<disk/> and <interface/>. This is incompatible with the older os/boot
element. Since not all hypervisors support per-device boot
specification, new deviceboot flag is included in capabilities XML for
hypervisors which understand the new boot element. Presence of the flag
allows (but doesn't require) users to use the new style boot order
specification.
This is in response to a request in:
https://bugzilla.redhat.com/show_bug.cgi?id=665293
In short, under heavy load, it's possible for qemu's networking to
lock up due to the tap device's default 1MB sndbuf being
inadequate. adding "sndbuf=0" to the qemu commandline -netdevice
option will alleviate this problem (sndbuf=0 actually sets it to
0xffffffff).
Because we must be able to explicitly specify "0" as a value, the
standard practice of "0 means not specified" won't work here. Instead,
virDomainNetDef also has a sndbuf_specified, which defaults to 0, but
is set to 1 if some value was given.
The sndbuf value is put inside a <tune> element of each <interface> in
the domain. The intent is that further tunable settings will also be
placed inside this element.
<interface type='network'>
...
<tune>
<sndbuf>0</sndbuf>
...
</tune>
</interface>
This patch is in response to
https://bugzilla.redhat.com/show_bug.cgi?id=643050
The existing libvirt support for the vhost-net backend to the virtio
network driver happens automatically - if the vhost-net device is
available, it is always enabled, otherwise the standard userland
virtio backend is used.
This patch makes it possible to force whether or not vhost-net is used
with a bit of XML. Adding a <driver> element to the interface XML, eg:
<interface type="network">
<model type="virtio"/>
<driver name="vhost"/>
will force use of vhost-net (if it's not available, the domain will
fail to start). if driver name="qemu", vhost-net will not be used even
if it is available.
If there is no <driver name='xxx'/> in the config, libvirt will revert
to the pre-existing automatic behavior - use vhost-net if it's
available, and userland backend if vhost-net isn't available.
Extend the virDomainFeature enumeration to include HAP (hardware
assisted paging) feature.
Hardware features such as Extended Page Table and Nested Page
Table augment hypervisor software techniques such as shadow
page table. Adding HAP to the virDomainFeature enumeration
allows users to select between hardware and software memory
management mechanisms for their guests.
If invalid type is specified, e.g.
<serial type='foo'>
<target port='0'/>
</serial>
We replace 'foo' with "null" type implicitly, without reporting an
error message to tell the user, and "start" or "edit" the domain
will be success.
It's not good to guess what the user wants, This patch is to fix
the problem.
* src/conf/domain_conf.c
This is partially in response to
https://bugzilla.redhat.com/show_bug.cgi?id=653300
The crash in that report was coincidentally fixed when we switched
from using inet_pton() to using virSocketParseAddr(), but the absence
of an ip address in a dhcp static host definition was still silently
ignored (and that entry discarded from the saved XML). This patch
turns that into a logged failure; likewise if the entry has neither a
mac address nor a name attribute (the entry is useless without at
least one of those, plus an ip address).
Since the network name is now pulled into this function in order for
those error logs to be more informative, the other error messages in
the function have also been changed to take advantage.
Running an instance of the router advertisement daemon (radvd) allows
guests using the virtual network to automatically acquire an IPv6
address and default route. Note that acquiring an address only works
for networks with a prefix length of exactly 64 - radvd is still run
in other circumstances, and still advertises routes, but autoconf will
not work because it requires exactly 64 bits of address info from the
network prefix.
This patch avoids a race condition with the pidfile by manually
daemonizing radvd rather than allowing it to daemonize itself, then
creating our own pidfile (in addition to radvd's own file, which is
unnecessary, but there is no way to tell radvd to not create it). This
is accomplished by exec'ing it with "--debug 1" in the commandline,
and using virCommand's features to fork, create a pidfile, and detach
from the newly forked process.
This commit adds support for IPv6 parsing and formatting to the
virtual network XML parser, including moving around data definitions
to allow for multiple <ip> elements on a single network, but only
changes the consumers of this API to accommodate for the changes in
API/structure, not to add any actual IPv6 functionality. That will
come in a later patch - this patch attempts to maintain the same final
functionality in both drivers that use the network XML parser - vbox
and "bridge" (the Linux bridge-based driver used by the qemu
hypervisor driver).
* src/libvirt_private.syms: Add new private API functions.
* src/conf/network_conf.[ch]: Change C data structure and
parsing/formatting.
* src/network/bridge_driver.c: Update to use new parser/formatter.
* src/vbox/vbox_tmpl.c: update to use new parser/formatter
* docs/schemas/network.rng: changes to the schema -
* there can now be more than one <ip> element.
* ip address is now an ip-addr (ipv4 or ipv6) rather than ipv4-addr
* new optional "prefix" attribute that can be used in place of "netmask"
* new optional "family" attribute - "ipv4" or "ipv6"
(will default to ipv4)
* define data types for the above
* tests/networkxml2xml(in|out)/nat-network.xml: add multiple <ip> elements
(including IPv6) to a single network definition to verify they are being
correctly parsed and formatted.
