The new introduced optional attribute "copy_on_read</code> controls
whether to copy read backing file into the image file. The value can
be either "on" or "off". Copy-on-read avoids accessing the same backing
file sectors repeatedly and is useful when the backing file is over a
slow network. By default copy-on-read is off.

Address side effect of accessing a variable via an index: Filters
accessing a variable where an element is accessed that is beyond the
size of the list (for example $TEST[10] and only 2 elements are available)
cannot instantiate that filter. Test for this and report proper error
to user.

This patch introduces the capability to use a different iterator per
variable.

The currently supported notation of variables in a filtering rule like

  <rule action='accept' direction='out'>
     <tcp  srcipaddr='$A' srcportstart='$B'/>
  </rule>

processes the two lists 'A' and 'B' in parallel. This means that A and B
must have the same number of 'N' elements and that 'N' rules will be 
instantiated (assuming all tuples from A and B are unique).

In this patch we now introduce the assignment of variables to different
iterators. Therefore a rule like

  <rule action='accept' direction='out'>
     <tcp  srcipaddr='$A[@1]' srcportstart='$B[@2]'/>
  </rule>

will now create every combination of elements in A with elements in B since
A has been assigned to an iterator with Id '1' and B has been assigned to an
iterator with Id '2', thus processing their value independently.

The first rule has an equivalent notation of

  <rule action='accept' direction='out'>
     <tcp  srcipaddr='$A[@0]' srcportstart='$B[@0]'/>
  </rule>

Most severe here is a latent (but currently untriggered) memory leak
if any hypervisor ever adds a string interface property; the
remainder are mainly cosmetic.

* include/libvirt/libvirt.h.in (VIR_DOMAIN_BANDWIDTH_*): Move
macros closer to interface that uses them, and document type.
* src/libvirt.c (virDomainSetInterfaceParameters)
(virDomainGetInterfaceParameters): Formatting tweaks.
* daemon/remote.c (remoteDispatchDomainGetInterfaceParameters):
Avoid memory leak.
* src/libvirt_public.syms (LIBVIRT_0.9.9): Sort lines.
* src/libvirt_private.syms (domain_conf.h): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSetInterfaceParameters): Fix
comments, break long lines.

Add a util function virDomainNetFind to find a domain's net def.

In order to avoid situation where a USB device is
in use by two domains, we must keep a list of already
attached devices like we do for PCI.

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

The virDomainEventCallbackList and virDomainEventQueue APIs are
now solely helpers used internally by virDomainEventState APIs.
Remove their decls from domain_event.h since no driver code should
need to use them any more.

* src/conf/domain_event.c: Make virDomainEventCallbackList and
  virDomainEventQueue APIs static & remove some unused APIs
* src/conf/domain_event.h, src/libvirt_private.syms: Remove
  virDomainEventCallbackList and virDomainEventQueue APIs

While virDomainEventState has APIs for managing removal of callbacks,
while locked, adding callbacks in the first place requires direct
access to the virDomainEventCallbackList structure. This is not
threadsafe since it is bypassing the virDomainEventState locks

* src/conf/domain_event.c, src/conf/domain_event.h,
  src/libvirt_private.syms: Add APIs for managing callbacks
  via virDomainEventState.

When registering a callback for a particular event some callers
need to know how many callbacks already exist for that event.
While it is possible to ask for a count, this is not free from
race conditions when threaded. Thus the API for registering
callbacks should return the count of callbacks. Also rename
virDomainEventStateDeregisterAny to virDomainEventStateDeregisterID

* src/conf/domain_event.c, src/conf/domain_event.h,
  src/libvirt_private.syms: Return count of callbacks when
  registering callbacks
* src/libxl/libxl_driver.c, src/libxl/libxl_driver.c,
  src/qemu/qemu_driver.c, src/remote/remote_driver.c,
  src/remote/remote_driver.c, src/uml/uml_driver.c,
  src/vbox/vbox_tmpl.c, src/xen/xen_driver.c: Update
  for change in APIs

This chunk of code below repeated in several functions, factor it into
a helper method virDomainLiveConfigHelperMethod to eliminate duplicated code
based on Eric and Adam's suggestion. I have tested it for all the
relevant APIs changed.
Signed-off-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NLei Li <lilei@linux.vnet.ibm.com>

On RHEL 5, with libxml2-2.6.26, the build failed with:
virsh.c: In function 'vshNodeIsSuperset':
virsh.c:11951: warning: implicit declaration of function 'xmlChildElementCount'

(or if warnings aren't errors, a link failure later on).

* src/util/xml.h (virXMLChildElementCount): New prototype.
* src/util/xml.c (virXMLChildElementCount): New function.
* src/libvirt_private.syms (xml.h): Export it.
* tools/virsh.c (vshNodeIsSuperset): Use it.

The Mingw32 linker highlighted that the symbols for virtime.h
declared in libvirt_private.syms were incorrect

* src/libvirt_private.syms: Fix virtime.h symbols

The virTimestamp and virTimeMs functions in src/util/util.h
duplicate functionality from virtime.h, in a non-async signal
safe manner. Remove them, and convert all code over to the new
APIs.

* src/util/util.c, src/util/util.h: Delete virTimeMs and virTimestamp
* src/lxc/lxc_driver.c, src/qemu/qemu_domain.c,
  src/qemu/qemu_driver.c, src/qemu/qemu_migration.c,
  src/qemu/qemu_process.c, src/util/event_poll.c: Convert to use
  virtime APIs

The logging APIs need to be able to generate formatted timestamps
using only async signal safe functions. This rules out using
gmtime/localtime/malloc/gettimeday(!) and much more.

Introduce a new internal API which is async signal safe.

  virTimeMillisNowRaw replacement for gettimeofday. Uses clock_gettime
                      where available, otherwise falls back to the unsafe
                      gettimeofday

  virTimeFieldsNowRaw  replacements for gmtime(), convert a timestamp
  virTimeFieldsThenRaw into a broken out set of fields. No localtime()
                       replacement is provided, because converting to
                       local time is not practical with only async signal
                       safe APIs.

  virTimeStringNowRaw  replacements for strftime() which print a timestamp
  virTimeStringThenRaw into a string, using a pre-determined format, with
                       a fixed size buffer (VIR_TIME_STRING_BUFLEN)

For each of these there is also a version without the Raw postfix
which raises a full libvirt error. These versions are not async
signal safe

* src/Makefile.am, src/util/virtime.c, src/util/virtime.h: New files
* src/libvirt_private.syms: New APis
* configure.ac: Check for clock_gettime in -lrt
* tests/virtimetest.c, tests/Makefile.am: Test new APIs

Fix the build on Mingw32 by removing the now obsolete
virGetPMCapabilities symbol from the private exports file

* src/libvirt_private.syms: Remove virGetPMCapabilities

* src/libvirt_private.syms: Export virNodeSuspendSupportsTarget
  and virNodeSuspendGetTargetMask

Implement setting/getting per-device blkio weights in qemu,
using the cgroups blkio.weight_device tunable.

This adds per-device weights to <blkiotune>.  Note that the
cgroups implementation only supports weights per block device,
and not per-file within the device; hence this option must be
global to the domain definition rather than tied to individual
<devices>/<disk> entries:

<domain ...>
  <blkiotune>
    <device>
      <path>/path/to/block</path>
      <weight>1000</weight>
    </device>
  </blkiotune>
..

This patch also adds a parameter --device-weights to virsh command
blkiotune for setting/getting blkiotune.weight_device for any
hypervisor that supports it.  All <device> entries under
<blkiotune> are concatenated into a single string attribute under
virDomain{Get,Set}BlkioParameters, named "device_weight".
Signed-off-by: NHu Tao <hutao@cn.fujitsu.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

Add the core functions that implement the functionality of the API.
Suspend is done by using an asynchronous mechanism so that we can return
the status to the caller before the host gets suspended. This asynchronous
operation is achieved by suspending the host in a separate thread of
execution. However, returning the status to the caller is only best-effort,
but not guaranteed.

To resume the host, an RTC alarm is set up (based on how long we want to
suspend) before suspending the host. When this alarm fires, the host
gets woken up.

Suspend-to-RAM operation on a host running Linux can take upto more than 20
seconds, depending on the load of the system. (Freezing of tasks, an operation
preceding any suspend operation, is given up after a 20 second timeout).
And Suspend-to-Disk can take even more time, considering the time required
for compaction, creating the memory image and writing it to disk etc.
So, we do not allow the user to specify a suspend duration of less than 60
seconds, to be on the safer side, since we don't want to prematurely declare
failure when we only had to wait for some more time.

In preparation of DHCP Snooping and the detection of multiple IP
addresses per interface:

The hash table that is used to collect the detected IP address of an
interface can so far only handle one IP address per interface. With
this patch we extend this to allow it to handle a list of IP addresses.

Above changes the returned variable type of virNWFilterGetIpAddrForIfname()
from char * to virNWFilterVarValuePtr; adapt all existing functions calling
this function.

This patch adds support for filtering of STP (spanning tree protocol) traffic
to the parser and makes us of the ebtables support for STP filtering. This code
now enables the filtering of traffic in chains with prefix 'stp'.
Signed-off-by: NStefan Berger <stefanb@linux.vnet.ibm.com>

This patch exports KVM Host Power Management capabilities as XML so that
higher-level systems management software can make use of these features
available in the host.

The script "pm-is-supported" (from pm-utils package) is run to discover if
Suspend-to-RAM (S3) or Suspend-to-Disk (S4) is supported by the host.
If either of them are supported, then a new tag "<power_management>" is
introduced in the XML under the <host> tag.

However in case the query to check for power management features succeeded,
but the host does not support any such feature, then the XML will contain
an empty <power_management/> tag. In the event that the PM query itself
failed, the XML will not contain any "power_management" tag.

To use this, new APIs could be implemented in libvirt to exploit power
management features such as S3/S4.

Now, when we support multiple consoles per domain,
the vm->def->console[0] can still remain an alias
for vm->def->serial[0]; However, we need to copy
it's source definition as well otherwise we'll regress
on virDomainOpenConsole.

Mingw32 complains if you request export of a symbol which does
not in fact exist.

* src/libvirt_bridge.syms, src/libvirt_macvtap.syms: Delete
  obsolete files
* src/libvirt_private.syms: Remove virNetServerGetDBusConn
* src/libvirt_dbus.syms: Add virNetServerGetDBusConn

This patch extends the NWFilter driver for Linux (ebiptables) to create
rules for each member of a previously introduced list. If for example
an attribute value (internally) looks like this:

IP = [10.0.0.1, 10.0.0.2, 10.0.0.3]

then 3 rules will be generated for a rule accessing the variable 'IP',
one for each member of the list. The effect of this is that this now
allows for filtering for multiple values in one field. This can then be
used to support for filtering/allowing of multiple IP addresses per
interface.

An iterator is introduced that extracts each member of a list and
puts it into a hash table which then is passed to the function creating
a rule. For the above example the iterator would cause 3 loops.
Signed-off-by: NStefan Berger <stefanb@linux.vnet.ibm.com>

NWFilters can be provided name-value pairs using the following
XML notation:

      <filterref filter='xyz'>
        <parameter name='PORT' value='80'/>
        <parameter name='VAL' value='abc'/>
      </filterref>

The internal representation currently is so that a name is stored as a
string and the value as well. This patch now addresses the value part of it
and introduces a data structure for storing a value either as a simple
value or as an array for later support of lists.

This patch adjusts all code that was handling the values in hash tables
and makes it use the new data type.
Signed-off-by: NStefan Berger <stefanb@linux.vnet.ibm.com>

Add a function to the virHashTable for getting an array of the hash table's
key-value pairs and have the keys (optionally) sorted.
Signed-off-by: NStefan Berger <stefanb@linux.vnet.ibm.com>

Fix ordering of symbols after re-arranging network device
management API source files

* src/libvirt_private.syms: Fix ordering

Move the ifaceMacvtapLinkDump and ifaceGetNthParent functions
into virnetdevvportprofile.c since they are specific to that
code. This avoids polluting the headers with the Linux specific
netlink data types

* src/util/interface.c, src/util/interface.h: Move
  ifaceMacvtapLinkDump and ifaceGetNthParent functions and delete
  remaining file
* src/util/virnetdevvportprofile.c: Add ifaceMacvtapLinkDump
  and ifaceGetNthParent functions
* src/network/bridge_driver.c, src/nwfilter/nwfilter_gentech_driver.c,
  src/nwfilter/nwfilter_learnipaddr.c, src/util/virnetdevmacvlan.c:
  Remove include of interface.h

Rename ifaceIsVirtualFunction to virNetDevIsVirtualFunction,
ifaceGetVirtualFunctionIndex to virNetDevGetVirtualFunctionIndex
and ifaceGetPhysicalFunction to virNetDevGetPhysicalFunction

* src/util/interface.c, src/util/interface.h: Rename APIs
* src/util/virnetdevvportprofile.c: Update for API rename

Rename the ifaceCheck method to virNetDevValidateConfig and change
so that it always raises an error and returns -1 on error.

* src/util/interface.c, src/util/interface.h: Rename ifaceCheck
  to virNetDevValidateConfig
* src/nwfilter/nwfilter_gentech_driver.c,
  src/nwfilter/nwfilter_learnipaddr.c: Update for API rename

To match up with the existing virNetDevSetIPv4Address, rename
ifaceGetIPAddress to virNetDevGetIPv4Address

* util/interface.h, util/interface.c: Rename API
* network/bridge_driver.c: Update for API rename

Rename the ifaceGetIndex method to virNetDevGetIndex and
ifaceGetVlanID to virNetDevGetVLanID. Also change the error
reporting behaviour to always raise errors and return -1 on
failure

* util/interface.c, util/interface.h: Rename ifaceGetIndex
  and ifaceGetVLAN
* nwfilter/nwfilter_gentech_driver.c, nwfilter/nwfilter_learnipaddr.c,
  nwfilter/nwfilter_learnipaddr.c, util/virnetdevvportprofile.c: Update
  for API renames and error handling changes

Rename ifaceReplaceMacAddress to virNetDevReplaceMacAddress
and ifaceRestoreMacAddress to virNetDevRestoreMacAddress.

* util/interface.c, util/interface.h, util/virnetdevmacvlan.c:
  Rename APIs

Rename ifaceMacvtapLinkAdd to virNetDevMacVLanCreate and
ifaceLinkDel to virNetDevMacVLanDelete. Strictly speaking
the latter isn't restricted to macvlan devices, but that's
the only use libvirt has for it.

* util/interface.c, util/interface.h,
  util/virnetdevmacvlan.c: Rename APIs

In preparation for code re-organization, rename the Macvtap
management APIs to have the following patterns

  virNetDevMacVLanXXXXX     - macvlan/macvtap interface management
  virNetDevVPortProfileXXXX - virtual port profile management

* src/util/macvtap.c, src/util/macvtap.h: Rename APIs
* src/conf/domain_conf.c, src/network/bridge_driver.c,
  src/qemu/qemu_command.c, src/qemu/qemu_command.h,
  src/qemu/qemu_driver.c, src/qemu/qemu_hotplug.c,
  src/qemu/qemu_migration.c, src/qemu/qemu_process.c,
  src/qemu/qemu_process.h: Update for renamed APIs

I missed adding virNetServerGetDBusConn() to libvirtd_private.syms
in commit b8adfcc6, which didn't cause a problem in 0.9.6 but
results in this build error in 0.9.7

libvirtd-remote.o: In function `remoteDispatchAuthPolkit':
remote.c:(.text+0x188dd): undefined reference to `virNetServerGetDBusConn'