Including QEMU, LXC, UML, XEN drivers.

This patch updates the structures that store information about each
domain and each hypervisor to support multiple security labels and
drivers. It also updates all the remaining code to use the new fields.
Signed-off-by: NMarcelo Cerri <mhcerri@linux.vnet.ibm.com>

As the consensus in:
https://www.redhat.com/archives/libvir-list/2012-July/msg01692.html,
this patch is to destroy conf/virdomainlist.[ch], folding the
helpers into conf/domain_conf.[ch].

* src/Makefile.am:
  - Various indention fixes incidentally
  - Add macro DATATYPES_SOURCES (datatypes.[ch])
  - Link datatypes.[ch] for libvirt_lxc

* src/conf/domain_conf.c:
  - Move all the stuffs from virdomainlist.c into it
  - Use virUnrefDomain and virUnrefDomainSnapshot instead of
    virDomainFree and virDomainSnapshotFree, which are defined
    in libvirt.c, and we don't want to link to it.
  - Remove "if" before "free" the object, as virObjectUnref
    is in the list "useless_free_options".

* src/conf/domain_conf.h:
  - Move all the stuffs from virdomainlist.h into it
  - s/LIST_FILTER/LIST_DOMAINS_FILTER/

* src/libxl/libxl_driver.c:
  - s/LIST_FILTER/LIST_DOMAINS_FILTER/
  - no (include "virdomainlist.h")

* src/libxl/libxl_driver.c: Likewise

* src/lxc/lxc_driver.c: Likewise

* src/openvz/openvz_driver.c: Likewise

* src/parallels/parallels_driver.c: Likewise

* src/qemu/qemu_driver.c: Likewise

* src/test/test_driver.c: Likewise

* src/uml/uml_driver.c: Likewise

* src/vbox/vbox_tmpl.c: Likewise

* src/vmware/vmware_driver.c: Likewise

* tools/virsh-domain-monitor.c: Likewise

* tools/virsh.c: Likewise

The meat of this patch is just moving the calls to
virNWFilterRegisterCallbackDriver from each hypervisor's "register"
function into its "initialize" function. The rest is just code
movement to allow that, and a new virNWFilterUnRegisterCallbackDriver
function to undo what the register function does.

The long explanation:

There is an array in nwfilter called callbackDrvArray that has
pointers to a table of functions for each hypervisor driver that are
called by nwfilter. One of those function pointers is to a function
that will lock the hypervisor driver. Entries are added to the table
by calling each driver's "register" function, which happens quite
early in libvirtd's startup.

Sometime later, each driver's "initialize" function is called. This
function allocates a driver object and stores a pointer to it in a
static variable that was previously initialized to NULL. (and here's
the important part...) If the "initialize" function fails, the driver
object is freed, and that pointer set back to NULL (but the entry in
nwfilter's callbackDrvArray is still there).

When the "lock the driver" function mentioned above is called, it
assumes that the driver was successfully loaded, so it blindly tries
to call virMutexLock on "driver->lock".

BUT, if the initialize never happened, or if it failed, "driver" is
NULL. And it just happens that "lock" is always the first field in
driver so it is also NULL.

Boom.

To fix this, the call to virNWFilterRegisterCallbackDriver for each
driver shouldn't be called until the end of its (*already guaranteed
successful*) "initialize" function, not during its "register" function
(which is currently the case). This implies that there should also be
a virNWFilterUnregisterCallbackDriver() function that is called in a
driver's "shutdown" function (although in practice, that function is
currently never called).

Update the LXC driver to use the virNetClient APIs for
connecting to the libvirt_lxc monitor, instead of the
low-level socket APIs. This is a step towards running
a full RPC protocol with libvirt_lxc
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Update all LXC code to use virReportError instead of the custom
lxcError macro
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Rename the lxc_driver_t struct typedef to virLXCDriver to more
closely follow normal libvirt naming conventions
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

For consistency all the APIs in the lxc_domain.c file should
have a virLXCDomain prefix in their name
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

For consistency all the APIs in the lxc_process.c file should
have a virLXCProcess prefix in their name
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Any time we have a string with no % passed through gettext, a
translator can inject a % to cause a stack overread.  When there
is nothing to format, it's easier to ask for a string that cannot
be used as a formatter, by using a trivial "%s" format instead.

In the past, we have used --disable-nls to catch some of the
offenders, but that doesn't get run very often, and many more
uses have crept in.  Syntax check to the rescue!

The syntax check can catch uses such as
virReportError(code,
               _("split "
                 "string"));
by using a sed script to fold context lines into one pattern
space before checking for a string without %.

This patch is just mechanical insertion of %s; there are probably
several messages touched by this patch where we would be better
off giving the user more information than a fixed string.

* cfg.mk (sc_prohibit_diagnostic_without_format): New rule.
* src/datatypes.c (virUnrefConnect, virGetDomain)
(virUnrefDomain, virGetNetwork, virUnrefNetwork, virGetInterface)
(virUnrefInterface, virGetStoragePool, virUnrefStoragePool)
(virGetStorageVol, virUnrefStorageVol, virGetNodeDevice)
(virGetSecret, virUnrefSecret, virGetNWFilter, virUnrefNWFilter)
(virGetDomainSnapshot, virUnrefDomainSnapshot): Add %s wrapper.
* src/lxc/lxc_driver.c (lxcDomainSetBlkioParameters)
(lxcDomainGetBlkioParameters): Likewise.
* src/conf/domain_conf.c (virSecurityDeviceLabelDefParseXML)
(virDomainDiskDefParseXML, virDomainGraphicsDefParseXML):
Likewise.
* src/conf/network_conf.c (virNetworkDNSHostsDefParseXML)
(virNetworkDefParseXML): Likewise.
* src/conf/nwfilter_conf.c (virNWFilterIsValidChainName):
Likewise.
* src/conf/nwfilter_params.c (virNWFilterVarValueCreateSimple)
(virNWFilterVarAccessParse): Likewise.
* src/libvirt.c (virDomainSave, virDomainSaveFlags)
(virDomainRestore, virDomainRestoreFlags)
(virDomainSaveImageGetXMLDesc, virDomainSaveImageDefineXML)
(virDomainCoreDump, virDomainGetXMLDesc)
(virDomainMigrateVersion1, virDomainMigrateVersion2)
(virDomainMigrateVersion3, virDomainMigrate, virDomainMigrate2)
(virStreamSendAll, virStreamRecvAll)
(virDomainSnapshotGetXMLDesc): Likewise.
* src/nwfilter/nwfilter_dhcpsnoop.c (virNWFilterSnoopReqLeaseDel)
(virNWFilterDHCPSnoopReq): Likewise.
* src/openvz/openvz_driver.c (openvzUpdateDevice): Likewise.
* src/openvz/openvz_util.c (openvzKBPerPages): Likewise.
* src/qemu/qemu_cgroup.c (qemuSetupCgroup): Likewise.
* src/qemu/qemu_command.c (qemuBuildHubDevStr, qemuBuildChrChardevStr)
(qemuBuildCommandLine): Likewise.
* src/qemu/qemu_driver.c (qemuDomainGetPercpuStats): Likewise.
* src/qemu/qemu_hotplug.c (qemuDomainAttachNetDevice): Likewise.
* src/rpc/virnetsaslcontext.c (virNetSASLSessionGetIdentity):
Likewise.
* src/rpc/virnetsocket.c (virNetSocketNewConnectUNIX)
(virNetSocketSendFD, virNetSocketRecvFD): Likewise.
* src/storage/storage_backend_disk.c
(virStorageBackendDiskBuildPool): Likewise.
* src/storage/storage_backend_fs.c
(virStorageBackendFileSystemProbe)
(virStorageBackendFileSystemBuild): Likewise.
* src/storage/storage_backend_rbd.c
(virStorageBackendRBDOpenRADOSConn): Likewise.
* src/storage/storage_driver.c (storageVolumeResize): Likewise.
* src/test/test_driver.c (testInterfaceChangeBegin)
(testInterfaceChangeCommit, testInterfaceChangeRollback):
Likewise.
* src/vbox/vbox_tmpl.c (vboxListAllDomains): Likewise.
* src/xenxs/xen_sxpr.c (xenFormatSxprDisk, xenFormatSxpr):
Likewise.
* src/xenxs/xen_xm.c (xenXMConfigGetUUID, xenFormatXMDisk)
(xenFormatXM): Likewise.

Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)

  You should have received a copy of the GNU General Public License
  along with Foobar.  If not, see <http://www.gnu.org/licenses/>.

This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').

Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:

  src/security/security_selinux.h
  src/security/security_driver.h
  src/security/security_selinux.c
  src/security/security_apparmor.h
  src/security/security_apparmor.c
  src/security/security_driver.c

The 'lxc_driver' global variable is now used from several of
the LXC sources files. Thus it needs to be non-static to
avoid runtime linkage errors
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>

Move all the code that manages stop/start of LXC processes
into separate lxc_process.{c,h} file to make the lxc_driver.c
file smaller
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Move the LXC driver code related to the virDomainObjPtr
private data into separate lxc_domain.{c,h} files
to reduce the size of lxc_driver.c
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

When sending SIGHUP to libvirtd, it will trigger the virStateDriver
reload operation. This is intended to reload the configuration files
for guests. For unknown historical reasons this is also triggering
autostart of all guests. Autostart is generally expected to be
something that happens on OS startup. Starting VMs on SIGHUP will
violate that expectation and potentially cause dangerous scenarios
if the admin has explicitly shutdown a misbehaving VM that has
been marked as autostart
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Introduce new members in the virMacAddr 'class'
- virMacAddrSet: set virMacAddr from a virMacAddr
- virMacAddrSetRaw: setting virMacAddr from raw 6 byte MAC address buffer
- virMacAddrGetRaw: writing virMacAddr into raw 6 byte MAC address buffer
- virMacAddrCmp: comparing two virMacAddr
- virMacAddrCmpRaw: comparing a virMacAddr with a raw 6 byte MAC address buffer

then replace raw MAC addresses by replacing

- 'unsigned char *' with virMacAddrPtr
- 'unsigned char ... [VIR_MAC_BUFLEN]' with virMacAddr

and introduce usage of above functions where necessary.

The only useful translation of "%s" as a format string is "%s" (I
suppose you could claim "%1$s" is also valid, but why bother).  So
it is not worth translating; fixing this exposes some instances
where we were failing to translate real error messages.  This makes
the fix of commit 097da1ab more generic, as well as ensuring no
future regressions.

* cfg.mk (sc_prohibit_useless_translation): New rule.
* src/lxc/lxc_driver.c (lxcSetVcpuBWLive): Fix offender.
* src/openvz/openvz_conf.c (openvzReadFSConf): Likewise.
* src/qemu/qemu_cgroup.c (qemuSetupCgroupForVcpu): Likewise.
* src/qemu/qemu_driver.c (qemuSetVcpusBWLive): Likewise.
* src/xenapi/xenapi_utils.c (xenapiSessionErrorHandle): Likewise.

This patch adds support for listing all domains into drivers that use
the common virDomainObj implementation: libxl, lxc, openvz, qemu, test,
uml, vmware.

For drivers that don't support managed save images the guests are
treated as if they had none, so filtering guests that do have such an
image on this driver succeeds and produces 0 results.

A core use case of the hook scripts is to be able to do things
to a guest's network configuration. It is possible to hook into
the 'start' operation for a QEMU guest which runs just before
the guest is started. The TAP devices will exist at this point,
but the QEMU process will not. It can be desirable to have a
'started' hook too, which runs once QEMU has started.

If libvirtd is restarted it will re-populate firewall rules,
but there is no QEMU hook to trigger for existing domains.
This is solved with a 'reconnect' hook.

Finally, if attaching to an external QEMU process there needs
to be an 'attach' hook script.

This all also applies to the LXC driver

* docs/hooks.html.in: Document new operations
* src/util/hooks.c, src/util/hooks.c: Add 'started', 'reconnect'
  and 'attach' operations for QEMU. Add 'prepare', 'started',
  'release' and 'reconnect' operations for LXC
* src/lxc/lxc_driver.c: Add hooks for 'prepare', 'started',
  'release' and 'reconnect' operations
* src/qemu/qemu_process.c: Add hooks for 'started', 'reconnect'
  and 'reconnect' operations

When getting number of CPUs the host has assigned, there was always
number "1" returned. Even though all lxc domains with no pinning
launched by libvirt run on all pCPUs (by default, no matter what's the
number), we should at least return the same number as the user
specified when creating the domain.

When the last reference to a virConnectPtr is released by
libvirtd, it was possible for a deadlock to occur in the
virDomainEventState functions. The virDomainEventStatePtr
holds a reference on virConnectPtr for each registered
callback. When removing a callback, the virUnrefConnect
function is run. If this causes the last reference on the
virConnectPtr to be released, then virReleaseConnect can
be run, which in turns calls qemudClose. This function has
a call to virDomainEventStateDeregisterConn which is intended
to remove all callbacks associated with the virConnectPtr
instance. This will try to grab a lock on virDomainEventState
but this lock is already held. Deadlock ensues

Thread 1 (Thread 0x7fcbb526a840 (LWP 23185)):

Since each callback associated with a virConnectPtr holds a
reference on virConnectPtr, it is impossible for the qemudClose
method to be invoked while any callbacks are still registered.
Thus the call to virDomainEventStateDeregisterConn must in fact
be a no-op. Thus it is possible to just remove all trace of
virDomainEventStateDeregisterConn and avoid the deadlock.

* src/conf/domain_event.c, src/conf/domain_event.h,
  src/libvirt_private.syms: Delete virDomainEventStateDeregisterConn
* src/libxl/libxl_driver.c, src/lxc/lxc_driver.c,
  src/qemu/qemu_driver.c, src/uml/uml_driver.c: Remove
  calls to virDomainEventStateDeregisterConn

To allow the security drivers to apply different configuration
information per hypervisor, pass the virtualization driver name
into the security manager constructor.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The driver->securityDriverName field may be NULL, if automatic
probing is used to determine security driver. This meant that
unless selinux was explicitly requested in lxc.conf, it was
not being sent to the libvirt_lxc process.

The driver->securityManager field is guaranteed non-NULL, since
there will always be the 'none' security driver present if
nothing else exists. So use that to set the driver name for
libvirt_lxc
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Currently the libvirt_lxc process uses VIR_DOMAIN_XML_INACTIVE
when loading the XML for the container. This means it loses
any dynamic data such as the, just allocated, SELinux label.

Further there is an inconsistency in the libvirt LXC driver
whereby it saves the live config XML and then later overwrites
the file with the live status XML instead. Add a comment about
this for future reference.

* src/lxc/lxc_controller.c: Remove VIR_DOMAIN_XML_INACTIVE
  when loading XML
* src/lxc/lxc_driver.c: Add comment about inconsistent
  config file formats
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Error: UNINIT:
/libvirt/src/lxc/lxc_driver.c:1412:
var_decl: Declaring variable "fd" without initializer.
/libvirt/src/lxc/lxc_driver.c:1460:
uninit_use_in_call: Using uninitialized value "fd" when calling "virFileClose".
/libvirt/src/util/virfile.c:50:
read_parm: Reading a parameter value.

Error: DEADCODE:
/libvirt/src/lxc/lxc_controller.c:960:
dead_error_condition: On this path, the condition "ret == 4" cannot be true.
/libvirt/src/lxc/lxc_controller.c:959:
at_most: After this line, the value of "ret" is at most -1.
/libvirt/src/lxc/lxc_controller.c:959:
new_values: Noticing condition "ret < 0".
/libvirt/src/lxc/lxc_controller.c:961:
dead_error_line: Execution cannot reach this statement "continue;".

Error: UNINIT:
/libvirt/src/lxc/lxc_controller.c:1104:
var_decl: Declaring variable "consoles" without initializer.
/libvirt/src/lxc/lxc_controller.c:1237:
uninit_use: Using uninitialized value "consoles".

The code is splattered with a mix of

  sizeof foo
  sizeof (foo)
  sizeof(foo)

Standardize on sizeof(foo) and add a syntax check rule to
enforce it
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Return statements with parameter enclosed in parentheses were modified
and parentheses were removed. The whole change was scripted, here is how:

List of files was obtained using this command:
git grep -l -e '\<return\s*([^()]*\(([^()]*)[^()]*\)*)\s*;' |             \
grep -e '\.[ch]$' -e '\.py$'

Found files were modified with this command:
sed -i -e                                                                 \
's_^\(.*\<return\)\s*(\(\([^()]*([^()]*)[^()]*\)*\))\s*\(;.*$\)_\1 \2\4_' \
-e 's_^\(.*\<return\)\s*(\([^()]*\))\s*\(;.*$\)_\1 \2\3_'

Then checked for nonsense.

The whole command looks like this:
git grep -l -e '\<return\s*([^()]*\(([^()]*)[^()]*\)*)\s*;' |             \
grep -e '\.[ch]$' -e '\.py$' | xargs sed -i -e                            \
's_^\(.*\<return\)\s*(\(\([^()]*([^()]*)[^()]*\)*\))\s*\(;.*$\)_\1 \2\4_' \
-e 's_^\(.*\<return\)\s*(\([^()]*\))\s*\(;.*$\)_\1 \2\3_'

Move error reporting out of the callers, into virURIParse
and virURIFormat, to get consistency.

* include/libvirt/virterror.h, src/util/virterror.c: Add VIR_FROM_URI
* src/util/viruri.c, src/util/viruri.h: Add error reporting
* src/esx/esx_driver.c, src/libvirt.c, src/libxl/libxl_driver.c,
  src/lxc/lxc_driver.c, src/openvz/openvz_driver.c,
  src/qemu/qemu_driver.c, src/qemu/qemu_migration.c,
  src/remote/remote_driver.c, src/uml/uml_driver.c,
  src/vbox/vbox_tmpl.c, src/vmx/vmx.c, src/xen/xen_driver.c,
  src/xen/xend_internal.c, tests/viruritest.c: Remove error
  reporting
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

This patch will allow OpenFlow controllers to identify which interface
belongs to a particular VM by using the Domain UUID.

ovs-vsctl get Interface vnet0 external_ids
{attached-mac="52:54:00:8C:55:2C", iface-id="83ce45d6-3639-096e-ab3c-21f66a05f7fa", iface-status=active, vm-id="142a90a7-0acc-ab92-511c-586f12da8851"}

V2 changes:
Replaced vm-uuid with vm-id. There was a discussion in Open vSwitch
mailinglist that we should stick with the same DB key postfixes for the
sake of consistency (e.g iface-id, vm-id ...).

On 64-bit platforms, unsigned long and unsigned long long are
identical, so we don't have to worry about overflow checks.
On 32-bit platforms, anywhere we narrow unsigned long long back
to unsigned long, we have to worry about overflow; it's easier
to do this in one place by having most of the code use the same
or wider types, and only doing the narrowing at the last minute.
Therefore, the memory set commands remain unsigned long, and
the memory get command now centralizes the overflow check into
libvirt.c, so that drivers don't have to repeat the work.

This also fixes a bug where xen returned the wrong value on
failure (most APIs return -1 on failure, but getMaxMemory
must return 0 on failure).

* src/driver.h (virDrvDomainGetMaxMemory): Use long long.
* src/libvirt.c (virDomainGetMaxMemory): Raise overflow.
* src/test/test_driver.c (testGetMaxMemory): Fix driver.
* src/rpc/gendispatch.pl (name_to_ProcName): Likewise.
* src/xen/xen_hypervisor.c (xenHypervisorGetMaxMemory): Likewise.
* src/xen/xen_driver.c (xenUnifiedDomainGetMaxMemory): Likewise.
* src/xen/xend_internal.c (xenDaemonDomainGetMaxMemory):
Likewise.
* src/xen/xend_internal.h (xenDaemonDomainGetMaxMemory):
Likewise.
* src/xen/xm_internal.c (xenXMDomainGetMaxMemory): Likewise.
* src/xen/xm_internal.h (xenXMDomainGetMaxMemory): Likewise.
* src/xen/xs_internal.c (xenStoreDomainGetMaxMemory): Likewise.
* src/xen/xs_internal.h (xenStoreDomainGetMaxMemory): Likewise.
* src/xenapi/xenapi_driver.c (xenapiDomainGetMaxMemory):
Likewise.
* src/esx/esx_driver.c (esxDomainGetMaxMemory): Likewise.
* src/libxl/libxl_driver.c (libxlDomainGetMaxMemory): Likewise.
* src/qemu/qemu_driver.c (qemudDomainGetMaxMemory): Likewise.
* src/lxc/lxc_driver.c (lxcDomainGetMaxMemory): Likewise.
* src/uml/uml_driver.c (umlDomainGetMaxMemory): Likewise.

Hooks may now be used as filters.

Function xmlParseURI does not remove square brackets around IPv6
address when parsing. One of the solutions is making wrappers around
functions working with xmlURI*. This assures that uri->server will be
always properly assigned and it doesn't have to be changed when used
on some new place in the code.
For this purpose, functions virParseURI and virSaveURI were
added. These function are wrappers around xmlParseURI and xmlSaveUri
respectively.
Also there is one new syntax check function to prohibit these functions
anywhere else.

File changes:
 - src/util/viruri.h        -- declaration
 - src/util/viruri.c        -- definition
 - src/libvirt_private.syms -- symbol export
 - src/Makefile.am          -- added source and header files
 - cfg.mk                   -- added sc_prohibit_xmlURI
 - all others               -- ID name and include fixes

This patch allows libvirt to add interfaces to already
existing Open vSwitch bridges. The following syntax in
domain XML file can be used:

    <interface type='bridge'>
      <mac address='52:54:00:d0:3f:f2'/>
      <source bridge='ovsbr'/>
      <virtualport type='openvswitch'>
        <parameters interfaceid='921a80cd-e6de-5a2e-db9c-ab27f15a6e1d'/>
      </virtualport>
      <address type='pci' domain='0x0000' bus='0x00'
                          slot='0x03' function='0x0'/>
    </interface>

or if libvirt should auto-generate the interfaceid use
following syntax:

    <interface type='bridge'>
      <mac address='52:54:00:d0:3f:f2'/>
      <source bridge='ovsbr'/>
      <virtualport type='openvswitch'>
      </virtualport>
      <address type='pci' domain='0x0000' bus='0x00'
                          slot='0x03' function='0x0'/>
    </interface>

It is also possible to pass an optional profileid. To do that
use following syntax:

   <interface type='bridge'>
     <source bridge='ovsbr'/>
     <mac address='00:55:1a:65:a2:8d'/>
     <virtualport type='openvswitch'>
       <parameters interfaceid='921a80cd-e6de-5a2e-db9c-ab27f15a6e1d'
                   profileid='test-profile'/>
     </virtualport>
   </interface>

To create Open vSwitch bridge install Open vSwitch and
run the following command:

    ovs-vsctl add-br ovsbr

An upcoming patch will add a <virtualport> element to interfaces of
type='bridge', so it makes sense to give this function a more generic
name.

For the sake of backwards compat, LXC guests are *not*
confined by default. This is because it is not practical
to dynamically relabel containers using large filesystem
trees. Applications can create confined containers though,
by giving suitable XML configs

* src/Makefile.am: Link libvirt_lxc to security drivers
* src/lxc/libvirtd_lxc.aug, src/lxc/lxc_conf.h,
  src/lxc/lxc_conf.c, src/lxc/lxc.conf,
  src/lxc/test_libvirtd_lxc.aug: Config file handling for
  security driver
* src/lxc/lxc_driver.c: Wire up security driver functions
* src/lxc/lxc_controller.c: Add a '--security' flag to
  specify which security driver to activate
* src/lxc/lxc_container.c, src/lxc/lxc_container.h: Set
  the process label just before exec'ing init.

Reusing common code makes things smaller; it also buys us some
additional safety, such as now rejecting duplicate parameters
during a set operation.

* src/qemu/qemu_driver.c (qemuDomainSetBlkioParameters)
(qemuDomainSetMemoryParameters, qemuDomainSetNumaParameters)
(qemuSetSchedulerParametersFlags)
(qemuDomainSetInterfaceParameters, qemuDomainSetBlockIoTune)
(qemuDomainGetBlkioParameters, qemuDomainGetMemoryParameters)
(qemuDomainGetNumaParameters, qemuGetSchedulerParametersFlags)
(qemuDomainBlockStatsFlags, qemuDomainGetInterfaceParameters)
(qemuDomainGetBlockIoTune): Use new helpers.
* src/esx/esx_driver.c (esxDomainSetSchedulerParametersFlags)
(esxDomainSetMemoryParameters)
(esxDomainGetSchedulerParametersFlags)
(esxDomainGetMemoryParameters): Likewise.
* src/libxl/libxl_driver.c
(libxlDomainSetSchedulerParametersFlags)
(libxlDomainGetSchedulerParametersFlags): Likewise.
* src/lxc/lxc_driver.c (lxcDomainSetMemoryParameters)
(lxcSetSchedulerParametersFlags, lxcDomainSetBlkioParameters)
(lxcDomainGetMemoryParameters, lxcGetSchedulerParametersFlags)
(lxcDomainGetBlkioParameters): Likewise.
* src/test/test_driver.c (testDomainSetSchedulerParamsFlags)
(testDomainGetSchedulerParamsFlags): Likewise.
* src/xen/xen_hypervisor.c (xenHypervisorSetSchedulerParameters)
(xenHypervisorGetSchedulerParameters): Likewise.

Based on qemu changes made in commits ae523427 and 659ded58.

* src/lxc/lxc_driver.c (lxcSetSchedulerParametersFlags)
(lxcGetSchedulerParametersFlags, lxcDomainSetBlkioParameters)
(lxcDomainGetBlkioParameters): Use helpers.
(lxcDomainSetBlkioParameters): Allow setting live and config at
once.

The lifetime of the virDomainEventState object is tied to
the lifetime of the driver, which in stateless drivers is
tied to the lifetime of the virConnectPtr.

If we add & remove a timer when allocating/freeing the
virDomainEventState object, we can get a situation where
the timer still triggers once after virDomainEventState
has been freed. The timeout callback can't keep a ref
on the event state though, since that would be a circular
reference.

The trick is to only register the timer when a callback
is registered with the event state & remove the timer
when the callback is unregistered.

The demo for the bug is to run

  while true ; do date ; ../tools/virsh -q -c test:///default 'shutdown test; undefine test; dominfo test' ; done

prior to this fix, it will frequently hang and / or
crash, or corrupt memory

Currently all drivers using domain events need to provide a callback
for handling a timer to dispatch events in a clean stack. There is
no technical reason for dispatch to go via driver specific code. It
could trivially be dispatched directly from the domain event code,
thus removing tedious boilerplate code from all drivers

Also fix the libxl & xen drivers to pass 'true' when creating the
virDomainEventState, since they run inside the daemon & thus always
expect events to be present.

* src/conf/domain_event.c, src/conf/domain_event.h: Internalize
  dispatch of events from timer callback
* src/libxl/libxl_driver.c, src/lxc/lxc_driver.c,
  src/qemu/qemu_domain.c, src/qemu/qemu_driver.c,
  src/remote/remote_driver.c, src/test/test_driver.c,
  src/uml/uml_driver.c, src/vbox/vbox_tmpl.c,
  src/xen/xen_driver.c: Remove all timer dispatch functions

* src/libxl/libxl_driver.c, src/lxc/lxc_driver.c,
  src/qemu/qemu_driver.c, src/remote/remote_driver.c,
  src/test/test_driver.c, src/uml/uml_driver.c,
  src/vbox/vbox_tmpl.c, src/xen/xen_driver.c: Convert
  to threadsafe APIs