This patch introduces the support for giving all devices a short,
unique name, henceforth known as a 'device alias'.  These aliases
are not set by the end user, instead being assigned by the hypervisor
if it decides it want to support this concept.

The QEMU driver sets them whenever using the -device arg syntax
and uses them for improved hotplug/hotunplug. it is the intent
that other APIs (block / interface stats & device hotplug) be
able to accept device alias names in the future.

The XML syntax is

   <alias name="video0"/>

This may appear in any type of device that supports device info.

* src/conf/domain_conf.c, src/conf/domain_conf.h: Add a 'alias'
  field to virDomainDeviceInfo struct & parse/format it in XML
* src/libvirt_private.syms: Export virDomainDefClearDeviceAliases
* src/qemu/qemu_conf.c: Replace use of "nic_name" field with the
  standard device alias
* src/qemu/qemu_driver.c: Clear device aliases at shutdown

The PCI device addresses are only valid while the VM is running,
since they are auto-assigned by QEMU. After shutdown they must
all be cleared. Future QEMU driver enhancement will allow for
persistent PCI address assignment

* src/conf/domain_conf.h, src/conf/domain_conf.c, src/libvirt_private.syms
  Add virDomainDefClearPCIAddresses() method for wiping out auto assigned
  PCI addresses
* src/qemu/qemu_driver.c: Clear PCI addresses at VM shutdown

Existing applications using libvirt are not aware of the disk
controller concept. Thus, after parsing the <disk> definitions
in the XML, it is neccessary to create <controller> elements
to satisfy all requested disks, as per their defined drive
addresses

* src/conf/domain_conf.c, src/conf/domain_conf.h,
  src/libvirt_private.syms: Add virDomainDefAddDiskControllers()
  method for populating disk controllers, and call it after
  parsing disk definitions.
* src/qemu/qemu_conf.c: Call virDomainDefAddDiskControllers()
  when doing ARGV -> XML conversion
* tests/qemuxml2argvdata/qemuxml2argv*.xml: Add disk controller
  data to all data files which don't have it already

It is perfectly acceptable to have multiple sound devices of
same type in guest configuration. If the underlying hypervisor
does not like this, it is its job to complain, not the XML
parser's

* src/conf/domain_conf.c: Remove hack which deleted duplicated
  sound device models.
* tests/xml2sexprdata/xml2sexpr-fv-sound.xml: Remove duplicate
  models

* src/conf/domain_conf.c: add defaults for the video device
* src/esx/esx_vmx.[ch]: add VNC support to the VMX handling
* tests/vmx2xmltest.c, tests/xml2vmxtest.c: add tests for the VNC support

* src/conf/domain_conf.c: Allow virDomainDeviceInfoIsSet,
  virDomainDeviceInfoClear & virDomainDeviceInfoFormat when
  building Xen proxy

This augments virDomainDevice with a <controller> element
that is used to represent disk controllers (e.g., scsi
controllers). The XML format is given by

  <controller type="scsi" index="<num>">
     <address type="pci" domain="0xNUM" bus="0xNUM" slot="0xNUM"/>
  </controller>

where type denotes the disk interface (scsi, ide,...), index
is an integer that identifies the controller for association
with disks, and the <address> element specifies the controller
address on the PCI bus as described in previous commits
The address element can be omitted; in this case, an address
will be assigned automatically.

Most of the code in this patch is from Wolfgang Mauerer's
previous disk controller series

 * docs/schemas/domain.rng: Define syntax for <controller>
   XML element
 * src/conf/domain_conf.c, src/conf/domain_conf.h: Define
   virDomainControllerDef struct, and routines for parsing
   and formatting XML
* src/libvirt_private.syms: Add virDomainControllerInsert
   and virDomainControllerDefFree

When parsing the <disk> element specification, if no <address>
is provided for the disk, then automatically assign one based on
the <target dev='sdXX'/> device name. This provides for backwards
compatability with existing applications using libvirt, while also
allowing new apps to have complete fine grained control.

* src/conf/domain_conf.h, src/conf/domain_conf.c,
  src/libvirt_private.syms: Add virDomainDiskDefAssignAddress()
  for assigning a controller/bus/unit address based on disk target
* src/qemu/qemu_conf.c: Call virDomainDiskDefAssignAddress() after
  generating XML from ARGV
* tests/qemuxml2argvdata/*.xml: Add in drive address information
  to all XML files

Add the virDomainDeviceAddress information to the sound, video
and watchdog devices. This means all of them gain the new XML
element

  <address .... />

This brings them upto par with disk/net/hostdev devices which
already have address info

* src/conf/domain_conf.h: Add virDomainDeviceAddress to sound,
  video & watchdog device struts.
* src/conf/domain_conf.c: Hook up parsing/formatting for
  virDomainDeviceAddress in sound, video & watchdog devices
* docs/schemas/domain.rng: Associate device address info
  with sound, video & watchdog

Introduce a new structure

      struct _virDomainDeviceDriveAddress {
        unsigned int controller;
        unsigned int bus;
        unsigned int unit;
      };

and plug that into virDomainDeviceAddress and generates XML that
looks like

  <address type='drive' controller='1' bus='0' unit='5'/>

This syntax will be used by the QEMU driver to explicitly control
how drives are attached to the bus

* src/conf/domain_conf.h, src/conf/domain_conf.c: Parsing and
  formatting of drive addresses
* docs/schemas/domain.rng: Define new address format for drives

All guest devices now use a common device address structure
summarized by:

  enum virDomainDeviceAddressType {
    VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE,
    VIR_DOMAIN_DEVICE_ADDRESS_TYPE_PCI,
  };

  struct _virDomainDevicePCIAddress {
    unsigned int domain;
    unsigned int bus;
    unsigned int slot;
    unsigned int function;
  };

  struct _virDomainDeviceInfo {
    int type;
    union {
        virDomainDevicePCIAddress pci;
    } addr;
  };

This replaces the anonymous structs in Disk/Net/Hostdev data
structures. Where available, the address is *always* printed
in the XML file, instead of being hidden in the internal state
file.

  <address type='pci' domain='0x0000' bus='0x1e' slot='0x07' function='0x0'/>

The structure definition is based on Wolfgang Mauerer's disk
controller patch series.

* docs/schemas/domain.rng: Define the <address> syntax and
  associate it with disk/net/hostdev devices
* src/conf/domain_conf.h, src/conf/domain_conf.c,
  src/libvirt_private.syms: APIs for parsing/formatting address
  information. Also remove the QEMU specific 'pci_addr' attributes
* src/qemu/qemu_driver.c: Replace use of 'pci_addr' attrs with
  new standardized format.

* include/libvirt/virterror.h src/util/virterror.c: add new domain
  VIR_FROM_CPU for errors
* src/conf/cpu_conf.c src/conf/cpu_conf.h: new parsing module
* src/Makefile.am proxy/Makefile.am: include new files
* src/conf/capabilities.[ch] src/conf/domain_conf.[ch]: reference
  new code
* src/libvirt_private.syms: private export of new entry points

Replace free(virBufferContentAndReset()) with virBufferFreeAndReset().
Update documentation and replace all remaining calls to free() with
calls to VIR_FREE(). Also add missing calls to virBufferFreeAndReset()
and virReportOOMError() in OOM error cases.

Since the monitor I/O is processed out of band from the main
thread(s) invoking monitor  commands, the virDomainObj may be
deleted by the I/O thread. The qemuDomainObjBeginJob takes an
extra reference to protect against final deletion, but this
reference is released by the corresponding EndJob call. THus
after the EndJob call it may not be valid to reference the
virDomainObj any more. To allow callers to detect this, the
EndJob call is changed to return the remaining reference count.

* src/conf/domain_conf.c: Make virDomainObjUnref return the
  remaining reference count
* src/qemu/qemu_driver.c: Avoid referencing virDomainObjPtr
  after qemuDomainObjEndJob if it has been deleted.

Now that drivers are using a private domain object state blob,
the virDomainObjFormat/Parse methods are no longer able to
directly serialize all neccessary state to/from XML. It is
thus neccessary to introduce a pair of callbacks fo serializing
private state.

The code for serializing vCPU PIDs and the monitor device
config can now move out of domain_conf.c and into the
qemu_driver.c where they belong.

* src/conf/capabilities.h: Add callbacks for serializing private
  state to/from XML
* src/conf/domain_conf.c, src/conf/domain_conf.h: Remove the
  monitor, monitor_chr, monitorWatch, nvcpupids and vcpupids
  fields from virDomainObjPtr. Remove code that serialized
  those fields
* src/libvirt_private.syms: Export virXPathBoolean
* src/qemu/qemu_driver.c: Add callbacks for serializing monitor
  and vcpupid data to/from XML
* src/qemu/qemu_monitor.h, src/qemu/qemu_monitor.c: Pass monitor
  char device config into qemuMonitorOpen directly.

* src/conf/domain_conf.c: don't call virDomainObjUnlock twice
* src/qemu/qemu_driver.c: relock driver lock if an error occurs in
  qemuDomainObjBeginJobWithDriver, enter/exit monitor with driver
  in qemudDomainSave

Introduce a new type="dir"  mode for <disks> that allows use of
QEMU's  virtual FAT block device driver. eg

    <disk type='dir' device='floppy'>
      <source dir='/tmp/test'/>
      <target dev='fda' bus='fdc'/>
      <readonly/>
    </disk>

gets turned into

  -drive file=fat:floppy:/tmp/test,if=floppy,index=0

Only read-only disks are supported with virtual FAT mode

* src/conf/domain_conf.c, src/conf/domain_conf.h: Add type="dir"
* docs/schemas/domain.rng: Document new disk type
* src/xen/xend_internal.c, src/xen/xm_internal.c: Raise error for
  unsupported disk types
* tests/qemuxml2argvdata/qemuxml2argv-disk-cdrom-empty.args: Fix
  empty disk file handling
* tests/qemuxml2argvdata/qemuxml2argv-disk-drive-fat.args,
  tests/qemuxml2argvdata/qemuxml2argv-disk-drive-fat.xml,
  tests/qemuxml2argvdata/qemuxml2argv-floppy-drive-fat.args,
  tests/qemuxml2argvdata/qemuxml2argv-floppy-drive-fat.xml
  tests/qemuxml2argvtest.c: Test QEMU vitual FAT driver
* src/qemu/qemu_conf.c: Support generating fat:/some/dir type
  disk args
* src/security/security_selinux.c: Temporarily skip labelling
  of directory based disks

If the virDomainDefPtr object has an 'id' of -1, then forcably
set the VIR_DOMAIN_XML_INACTIVE flag to ensure generated XML
does not include any cruft from the previously running guest
such as console PTY path, or VNC port.

* src/conf/domain_conf.c: Set VIR_DOMAIN_XML_INACTIVE if
  def->id is -1. Replace checks for def->id == -1 with
  check against flags & VIR_DOMAIN_XML_INACTIVE.

* src/conf/domain_conf.h src/conf/domain_conf.c: add the new entry in
  the enum and lists of virDomainDiskBus
* src/qemu/qemu_conf.c: same for virDomainDiskQEMUBus

Change the QEMU monitor file handle watch to poll for both
read & write events, as well as EOF. All I/O to/from the
QEMU monitor FD is now done in the event callback thread.

When the QEMU driver needs to send a command, it puts the
data to be sent into a qemuMonitorMessagePtr object instance,
queues it for dispatch, and then goes to sleep on a condition
variable. The event thread sends all the data, and then waits
for the reply to arrive, putting the response / error data
back into the qemuMonitorMessagePtr and notifying the condition
variable.

There is a temporary hack in the disk passphrase callback to
avoid acquiring the domain lock.  This avoids a deadlock in
the command processing, since the domain lock is still held
when running monitor commands. The next commit will remove
the locking when running commands & thus allow re-introduction
of locking the disk passphrase callback

* src/qemu/qemu_driver.c: Temporarily don't acquire lock in
  disk passphrase callback. To be reverted in next commit
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Remove
  raw I/O functions, and a generic qemuMonitorSend() for
  invoking a command
* src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h:
  Remove all low level I/O, and use the new qemuMonitorSend()
  API. Provide a qemuMonitorTextIOProcess() method for detecting
  command/reply/prompt boundaries in the monitor data stream

Add reference counting on the virDomainObjPtr objects. With the
forthcoming asynchronous QEMU monitor, it will be neccessary to
release the lock on virDomainObjPtr while waiting for a monitor
command response. It is neccessary to ensure one thread can't
delete a virDomainObjPtr while another is waiting. By introducing
reference counting threads can make sure objects they are using
are not accidentally deleted while unlocked.

* src/conf/domain_conf.h, src/conf/domain_conf.c: Add
  virDomainObjRef/Unref APIs, remove virDomainObjFree
* src/openvz/openvz_conf.c: replace call to virDomainObjFree
  with virDomainObjUnref

Use this function in the qemu, uml, lxc, and test drivers.

* include/libvirt/virterror.h src/util/virterror.c: add a new error
  VIR_ERR_CONFIG_UNSUPPORTED for valid but unsupported configuration options
* src/conf/domain_conf.c: Throw an error if guestfwd address isn't IPv4
  and cleanup a number of parsing return error values.

allows the following to be specified in a domain:
<channel type='pipe'>
  <source path='/tmp/guestfwd'/>
  <target type='guestfwd' address='10.0.2.1' port='4600'/>
</channel>

* proxy/Makefile.am: add network.c as dep of domain_conf.c
* docs/schemas/domain.rng src/conf/domain_conf.[ch]: extend the domain
  schemas and the parsing/serialization side for the new construct

QEmu support will add the following on the qemu command line:
 -chardev pipe,id=channel0,path=/tmp/guestfwd
 -net user,guestfwd=tcp:10.0.2.1:4600-chardev:channel0

* src/qemu/qemu_conf.c: Add argument output for channel
* tests/qemuxml2(argv|xml)test.c: Add test for <channel> domain syntax

A character device's target (it's interface in the guest) had only a
single property: port. This patch is in preparation for adding targets
which require other properties.
Since this changes the conf type for character devices this affects
a number of drivers:

* src/conf/domain_conf.[ch] src/esx/esx_vmx.c src/qemu/qemu_conf.c
  src/qemu/qemu_driver.c src/uml/uml_conf.c src/uml/uml_driver.c
  src/vbox/vbox_tmpl.c src/xen/xend_internal.c src/xen/xm_internal.c:
  target properties are moved into a union in virDomainChrDef, and a
  targetType field is added to identify which union member should be
  used. All current code which touches a virDomainChrDef is updated both
  to use the new union field, and to populate targetType if necessary.

- Don't duplicate SystemError
- Use proper error code in domain_conf
- Fix a broken error call in qemu_conf
- Don't use VIR_ERR_ERROR in security driver (isn't a valid code in this case)

When building with --disable-nls, I got a few messages like this:

storage/storage_backend.c: In function 'virStorageBackendCreateQemuImg':
storage/storage_backend.c:571: warning: format not a string literal and no format arguments

Fix these up.
Signed-off-by: NChris Lalancette <clalance@redhat.com>

Rename virDomainIsActive to virDomainObjIsActive, and
virInterfaceIsActive to virInterfaceObjIsActive and finally
virNetworkIsActive to virNetworkObjIsActive.

* src/conf/domain_conf.c, src/conf/domain_conf.h,
  src/conf/interface_conf.h, src/conf/network_conf.c,
  src/conf/network_conf.h, src/lxc/lxc_driver.c,
  src/network/bridge_driver.c, src/opennebula/one_driver.c,
  src/openvz/openvz_driver.c, src/qemu/qemu_driver.c,
  src/test/test_driver.c, src/uml/uml_driver.c: Update for
  renamed APIs.

Nearly all of the methods in src/util/util.h have error codes that
must be checked by the caller to correct detect & report failure.
Add ATTRIBUTE_RETURN_CHECK to ensure compile time validation of
this

* daemon/libvirtd.c: Add explicit check on return value of virAsprintf
* src/conf/domain_conf.c: Add missing check on virParseMacAddr return
  value status & report error
* src/network/bridge_driver.c: Add missing OOM check on virAsprintf
  and report error
* src/qemu/qemu_conf.c: Add missing check on virParseMacAddr return
  value status & report error
* src/security/security_selinux.c: Remove call to virRandomInitialize
  that's done in libvirt.c already
* src/storage/storage_backend_logical.c: Add check & log on virRun
  return status
* src/util/util.c: Add missing checks on virAsprintf/Run status
* src/util/util.h: Annotate all methods with ATTRIBUTE_RETURN_CHECK
  if they return an error status code
* src/vbox/vbox_tmpl.c: Add missing check on virParseMacAddr
* src/xen/xm_internal.c: Add missing checks on virAsprintf
* tests/qemuargv2xmltest.c: Remove bogus call to virRandomInitialize()

The virDomainObjPtr object stores state about a running domain.
This object is shared across all drivers so it is not appropriate
to include driver specific state here. This patch adds the ability
to request a blob of private data per domain object instance. The
driver must provide a allocator & deallocator for this purpose

THis patch abuses the virCapabilitiesPtr structure for storing the
allocator/deallocator callbacks, since it is already being abused
for other internal things relating to parsing. This should be moved
out into a separate object at some point.

* src/conf/capabilities.h: Add privateDataAllocFunc and
  privateDataFreeFunc fields
* src/conf/domain_conf.c: Invoke the driver allocators / deallocators
  when creating/freeing virDomainObjPtr instances.
* src/conf/domain_conf.h: Pass virCapsPtr into virDomainAssignDef
  to allow access to the driver specific allocator function
* src/lxc/lxc_driver.c, src/opennebula/one_driver.c,
  src/openvz/openvz_driver.c, src/qemu/qemu_driver.c,
  src/test/test_driver.c, src/uml/uml_driver.c: Update for
  change in virDomainAssignDef contract

The current virDomainObjListPtr object stores domain objects in
an array. This means that to find a particular objects requires
O(n) time, and more critically acquiring O(n) mutex locks.

The new impl replaces the array with a virHashTable, keyed off
UUID. Finding a object based on UUID is now O(1) time, and only
requires a single mutex lock. Finding by name/id is unchanged
in complexity.

In changing this, all code which iterates over the array had
to be updated to use a hash table iterator function callback.
Several of the functions which were identically duplicating
across all drivers were pulled into domain_conf.c

* src/conf/domain_conf.h, src/conf/domain_conf.c: Change
  virDomainObjListPtr to use virHashTable. Add a initializer
  method virDomainObjListInit, and rename virDomainObjListFree
  to virDomainObjListDeinit, since its not actually freeing
  the container, only its contents. Also add some convenient
  methods virDomainObjListGetInactiveNames,
  virDomainObjListGetActiveIDs and virDomainObjListNumOfDomains
  which can be used to implement the correspondingly named
  public API entry points in drivers
* src/libvirt_private.syms: Export new methods from domain_conf.h
* src/lxc/lxc_driver.c, src/opennebula/one_driver.c,
  src/openvz/openvz_conf.c, src/openvz/openvz_driver.c,
  src/qemu/qemu_driver.c, src/test/test_driver.c,
  src/uml/uml_driver.c, src/vbox/vbox_tmpl.c: Update all code
  to deal with hash tables instead of arrays for domains

This adds simple support for configuring a guest with a QEMU/KVM
virtual hardware watchdog device.

If one has e.g.

  <guest>
    <os_type>hvm</os_type>
    <arch name='x86_64'>
      <wordsize>64</wordsize>
      <emulator>/usr/bin/qemu-system-x86_64</emulator>
      <machine>pc-0.11</machine>
      <machine canonical='pc-0.11'>pc</machine>
      <machine>pc-0.10</machine>
      <machine>isapc</machine>
      <domain type='qemu'>
      </domain>
      <domain type='kvm'>
        <emulator>/usr/bin/kvm</emulator>
        <machine>pc</machine>
        <machine>isapc</machine>
      </domain>
    </arch>
  </guest>

and start a guest with:

  <domain type='kvm'>
    ...
    <os>
      <type arch='x86_64'>hvm</type>
      ...
    </os>
  </domain>

then the default machine type should be 'pc' and not 'pc-0.11'

Issue was reported by Anton Protopopov.

* src/capabilities.[ch]: pass the domain type to
  virCapabilitiesDefaultGuestArch() and use it to look up the default
  machine type from a specific guest domain if needed.

* src/conf/domain_conf.c, src/xen/xm_internal.c: update

* tests/qemuxml2argvdata/qemuxml2argv-machine-aliases2.xml: update
  the domain type to 'kvm' and remove the machine type to check
  that the default gets looked up correctly

* src/conf/domain_conf.c: a simple typo in an XML domain file could lead
  to a crash, because we called STRPREFIX() on the looked up value without
  checking it was non-null.

* src/conf/domain_conf.c: when declaring a <interface type="bridge">
  tag, <source> needs a "bridge" attribute, but the parser complains
  about a missing "dev" attribute.

* docs/schemas/domain.rng: allow one <description> tag in the top level
  of the <domain> to store user information as text
* src/conf/domain_conf.c src/conf/domain_conf.h: extend the structure
  to store this text, grab it at parse time and save it back when
  present after <uuid>

* src/conf/domain_conf.c: Don't assume all virDomainObjPtr have
  a non-NULL monitor_chr field in virDomainObjFormat.
* src/lxc/lxc_driver.c: Implement suspend/resume driver APis
* src/util/cgroup.c, src/util/cgroup.h: Support the 'freezer'
  cgroup controller
* src/libvirt_private.syms: Export virCgroupSetFreezerState
  and virCgroupGetFreezerState

* src/capabilities.c, src/capabilities.h, src/domain_conf.c,
  src/domain_conf.h, src/domain_event.c, src/domain_event.h,
  src/interface_conf.c, src/interface_conf.h,
  src/network_conf.c, src/network_conf.h, src/node_device_conf.c,
  src/node_device_conf.h, src/secret_conf.c, src/secret_conf.h,
  src/storage_conf.c, src/storage_conf.h, src/storage_encryption_conf.c,
  src/storage_encryption_conf.h: Move to src/conf/
* src/Makefile.am: Add -Isrc/conf to the individual build targets
  which need to use XML config APIs. Remove LIBXML_CFLAGS, LIBSSH2_CFLAGS
  and SELINUX_CFLAGS from global INCLUDES and only have them in build
  targets which actually need them.  Create a libvirt_conf.la
  convenience library for all config parsers
* src/hostusb.h: Remove bogus include of domain_conf.h
* tests/Makefile.am: Add -Isrc/conf. Remove bogus -I$builddir/src
  since it never has any generated header files
* daemon/Makefile.am: Add -Isrc/conf
* proxy/Makefile.am: Add -Isrc/conf and cope with renamed files
* src/hash.c: Remove bogus include of libxml/threads.h

* src/qemu_driver.c: Don't trust monitor for vcpu PID info on
  restart
* src/domain_conf.c: Save and load vCPU PID info from domain
  status file