Define the public API for (de-)registering network events
and the callbacks for receiving lifecycle events. The lifecycle
event includes a 'detail' parameter to match the domain lifecycle
event data, but this is currently unused.

The network events related code goes into its own set of internal
files src/conf/network_event.[ch]

Each unique event ID will thus be composed by 1 byte for the namespace
and 1 byte for a namespace-specific ID. The namespace for domain event
needs to be 0 for compatibility reasons.

The virDomainEvent class is kept as it indicates what meta informations
are valid for the children classes. This may be useful in the future.

RIP virDomainEvent union. All data are now stored in each
virObjectEvent subclass.

This change may be confusing at first, but provides a much more
consistent naming scheme for the virObjectEvent children construction
functions.

This aims at providing some consistency with other domain events

Added a parent class virObjectEvent for future event types

Keep virDomainEventStateRegisterID as a convenience wrapper around
this new function.

Keep the legacy Domain lifecycle event functions as is.

Leave virDomainEventRegister and its Deregister brother as these are
legacy functions only for domain lifecycle events.

The event queue will be generalized to hold events related
to any object type.

The metadata struct will hold the unique identifiers for
any type of object, though not all fields will be used
for all types.

The event callbacks will be generalized to handle events
for any object type.

When changing memtune limits to unlimited with AFFECT_CONFIG, the
values in virDomainDef are set to PARAM_UNLIMITED, which causes the
whole <memtune> to be formatted.  This can be changed in all drivers,
but it also makes sense to use the default (0) as another value for
"unlimited", since zero memory limit makes no sense.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

55bfd020 added a 'ram' attribute for qxl video devices
but didn't update the ABI check.

https://bugzilla.redhat.com/show_bug.cgi?id=1035123

https://bugzilla.redhat.com/show_bug.cgi?id=1035118

When outputting the XML for the RNG device, the code didn't format the
PCI address info. Additionally the schema wasn't expecting the info
although it was being parsed and used internally. Fix those mistakes and
add test for the PCI info section.

When changing the parsing and formatting functions in commit
43f2ccdc I forgot to update the qemu
disk alignment function for snapshots that automatically adds snapshot
configs for disks that were not mentioned in the XML. The function
allocated a new disk snapshot definition but did not correctly
initialize the snapshot disk source type variable. This resulted into
the disks considered as block devices and invalid XML was generated.

Reported by John Ferlan.

Kill the use of atoi() and introduce syntax check to forbid it and it's
friends (atol, atoll, atof, atoq).

Also fix a typo in variable name holding the cylinders count of a disk
pool (apparently unused).

examples/domsuspend/suspend.c will need a larger scale refactor as the
whole example file is broken thus it will be exempted from the syntax
check for now.

Before this patch, the translation function still needs a second ugly
helper function to actually format the command line for qemu. But if we
do the right stuff in the translation function, we don't have to bother
with the second function any more.

This patch removes the messy qemuBuildVolumeString function and changes
qemuTranslateDiskSourcePool to set stuff up correctly so that the
regular code paths meant for volumes can be used to format the command
line correctly.

For this purpose a new helper "qemuDiskGetActualType()" is introduced to
return the type of the volume in a pool.

As a part of the refactor the qemuTranslateDiskSourcePool function is
fixed to do decisions based on the pool type instead of the volume type.
This allows to separate pool-type-specific stuff more clearly and will
ease addition of other pool types that will require certain other
operations to get the correct pool source.

The previously fixed tests should make sure that we don't break stuff
that was working before.

Add virDomainDiskAuthClear to help cleaning out the struct in other
places too.

To simplify operations on virDomainDiskHostDef arrays we will need deep
copy and freeing functions. Add and properly export them.

Consider the following valid snapshot XML as the <driver> element is
allowed to be empty in the domainsnapshot.rng schema:

$ cat snap.xml
<domainsnapshot>
  <disks>
    <disk name='vda' snapshot='external'>
      <source file='/tmp/foo'/>
      <driver/>
    </disk>
  </disks>
</domainsnapshot>

produces the following error:

$ virsh snapshot-create domain snap.xml
error: internal error: unknown disk snapshot driver '(null)'

The driver type is parsed as NULL from the XML as the attribute is not
present and then directly used to produce the error message.

With this patch the attempt to parse the driver type is skipped if not
present to avoid changing the schema to forbid the empty driver element.

Disk source elements for snapshots were using separate code from our
config parser. As snapshots can be stored on more than just regular
files, we will need the universal parser to allow us to expose a variety
of snapshot disk targets. This patch reuses the config parsers and
formatters to do the job.

This initial support only changes the code without any visible XML
change.

This code will be reused in the snapshot disk definition parser.

The code is common for all the various disk types. Split it out to a
common function.

Avoid if statements when used with virBufferEscapeString which
automaticaly omits the whole string. Also add some line breaks to
visualy separate the code.

The <source> element formatting function was expecting a
virDomainDiskDefPtr to store the data. As snapshots are not using this
data structure to hold the data, we need to add an internal function
which splits out individual fields separately.

While running nwfilterxml2xmltest, it was found that valgrind pointed out the
following error...

==7466== 16 bytes in 1 blocks are definitely lost in loss record 26 of 90
==7466==    at 0x4A06B6F: calloc (vg_replace_malloc.c:593)
    ==7466==    by 0x4C651AD: virAlloc (viralloc.c:142)
    ==7466==    by 0x4D0450D: virNWFilterDefParseNode (nwfilter_conf.c:2575)
    ==7466==    by 0x4D05D84: virNWFilterDefParse (nwfilter_conf.c:2647)
    ==7466==    by 0x401FDE: testCompareXMLToXMLHelper (nwfilterxml2xmltest.c:39)
    ==7466==    by 0x402DE1: virtTestRun (testutils.c:138)
    ==7466==    by 0x4018E9: mymain (nwfilterxml2xmltest.c:111)
    ==7466==    by 0x403482: virtTestMain (testutils.c:593)
    ==7466==    by 0x341F421A04: (below main) (libc-start.c:225)

...21 times, which are related to 21 tests in nwfilterxml2xmltest.c which sent
EXPECT_WARN = false. There were two scenarios in virNWFilterDefParseXML(),
when the variable 'entry' was malloc'ed, but not freed.