All drivers have copy + pasted inadequate error reporting which wraps
util.c:virGetHostname. Move all error reporting to this function, and improve
what we report.

Changes from v1:
  Drop the driver wrappers around virGetHostname. This means we still need
  to keep the new conn argument to virGetHostname, but I think it's worth
  it.

Introduces several new public API options for migration

 - VIR_MIGRATE_PEER2PEER: With this flag the client only
   invokes the virDomainMigratePerform method, expecting
   the source host driver to do whatever is required to
   complete the entire migration process.
 - VIR_MIGRATE_TUNNELLED: With this flag the actual data
   for migration will be tunnelled over the libvirtd RPC
   channel. This requires that VIR_MIGRATE_PEER2PEER is
   also set.
 - virDomainMigrateToURI: This is variant of the existing
   virDomainMigrate method which does not require any
   virConnectPtr for the destination host. Given suitable
   driver support, this allows for all the same modes as
   virDomainMigrate()

The URI for VIR_MIGRATE_PEER2PEER must be a valid libvirt
URI. For non-p2p migration a hypervisor specific migration
URI is used.

virDomainMigrateToURI without a PEER2PEER flag is only
support for Xen currently, and it involves XenD talking
directly to XenD, no libvirtd involved at all.

* include/libvirt/libvirt.h.in: Add VIR_MIGRATE_PEER2PEER
  flag for migration
* src/libvirt_internal.h: Add feature flags for peer to
  peer migration (VIR_FEATURE_MIGRATE_P2P) and direct
  migration (VIR_MIGRATE_PEER2PEER mode)
* src/libvirt.c: Implement support for VIR_MIGRATE_PEER2PEER
  and virDomainMigrateToURI APIs.
* src/xen/xen_driver.c: Advertise support for DIRECT migration
* src/xen/xend_internal.c: Add TODO item for p2p migration
* src/libvirt_public.syms: Export virDomainMigrateToURI
  method
* src/qemu/qemu_driver.c: Add support for PEER2PEER and
  migration, and adapt TUNNELLED migration.
* tools/virsh.c: Add --p2p and --direct args and use the
  new virDomainMigrateToURI method where possible.

Add the virStrncpy function, which takes a dst string, source string,
the number of bytes to copy and the number of bytes available in the
dest string.  If the source string is too large to fit into the
destination string, including the \0 byte, then no data is copied and
the function returns NULL.  Otherwise, this function copies n bytes
from source into dst, including the \0, and returns a pointer to the
dst string.  This function is intended to replace all unsafe uses
of strncpy in the code base, since strncpy does *not* guarantee that
the buffer terminates with a \0.
Signed-off-by: NChris Lalancette <clalance@redhat.com>

* src/Makefile.am, src/proxy_internal.c, src/proxy_internal.h
  src/sexpr.c, src/sexpr.h, src/xen_unified.c, src/xen_unified.h,
  src/xen_internal.c, src/xen_internal.h, src/xen_inotify.c,
  src/xen_inotify.h, src/xend_internal.c, src/xend_internal.h,
  src/xm_internal.c, src/xm_internal.h, src/xs_internal.c,
  src/xs_internal.h: Move to src/xen/ directory
* proxy/Makefile.am, proxy/libvirt_proxy.c, src/Makefile.am,
  src/libvirt.c, tests/sexpr2xmltest.c, tests/statstest.c,
  tests/xencapstest.c, tests/xmconfigtest.c, tests/xml2sexprtest.c:
  Adapt to changed xen location
* src/stats_linux.h, src/stats_linux.c: Remove xen specific block
  stats APIs
* src/qemu_driver.c, src/uml_driver.c: Add missing sys/un.h include
  uncovered after change to stats_linux.h
* src/xen/block_stats.h, src/xen/block_stats.c: Add xen specific
  block stats APIs

* src/qemu_conf.c: Fix leak of values upon OOM
* src/xend_internal.c: Fix missing check for OOM failure
* tests/qemuargv2xmltest.c, tests/qemuxml2argvtest.c: Free
  stateDir upon exit to avoid leak

* src/xend_internal.c: in xenDaemonLookupByID() if virGetDomain fails
  free up the name

* src/xend_internal.c: free name in xenDaemonLookupByID() if
  virGetDomain() fails

* src/xend_internal.c (xenDaemonCreateXML): Don't set "ret" after
last use.

* src/xend_internal.c: Lookup guest after starting persistent
  config in order to refresh the domain ID field

Calling qsort() on the disks array causes disk to be
unneccessarily re-ordered, potentially breaking the
ability to boot if the boot disk gets moved later in
the list. The new algorithm will insert a new disk as
far to the end of the list as possible, while being
ordered correctly wrt other disks on the same bus.

* src/domain_conf.c, src/domain_conf.h: Remove disk sorting
  routines. Add API to insert a disk into existing list at
  the optimal position, without resorting disks
* src/libvirt_private.syms: Export virDomainDiskInsert
* src/xend_internal.c, src/xm_internal.c: Remove calls to
  qsort, use virDomainDiskInsert instead.
* src/qemu_driver.c: Remove calls to qsort, use virDoaminDiskInsert
  instead. Fix reordering bugs when hotunplugging disks and
  networks. Fix memory leak in disk/net unplug

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

* src/xend_internal.c: extraneous ; in xenDaemonParseSxprGraphicsNew

* src/xend_internal.c: the update on the cpu affinity map format
  had na error and made the changes in the wrong buffer, fix those

GCC >= 4.4 assumes the 'printf' attribute refers to the native
runtime libraries format specifiers. Thanks to gnulib, libvirt
has GNU format specifiers everywhere.  This means we need to
use 'gnu_printf' with GCC >= 4.4 to get correct compiler
checking of printf format specifiers.

* HACKING: Document new rules for ATTRIBUTE_FMT_PRINTF
* autobuild.sh, mingw32-libvirt.spec.in: Disable OpenNebula
  driver on mingw32 builds
* qemud/dispatch.h, qemud/qemu.h, src/buf.h src/internal.h,
  src/logging.h, src/security.h, src/sexpr.h, src/util.h,
  src/virterror_internal.h, src/xend_internal.c: Change
  over to ATTRIBUTE_FMT_PRINTF.
* src/virsh.c: Disable 'cd' and 'pwd' commands on Win32
  since they don't compile
* src/threads-win32.c: Add missing return value check

  xen versions, patch by Sascha, fixes #503254
daniel

  patch by Tatsuro Enokura
daniel

* src/domain_conf.c src/domain_conf.h: parse and save multiple
  graphics elements instead of one, patch by Pritesh Kothari
* src/qemu_conf.c src/qemu_driver.c: adapt the qemu/kvm driver for
  the new structures, patch by Pritesh Kothari
* src/xend_internal.c src/xm_internal.c: same thing for Xen drivers
Daniel

  if the domain is not running, patch by Takahashi Tomohiro
daniel

built-in TODO list for each driver.  Also rip out the internal getURI method;
it is never used by any of the drivers, and was buggy to boot.

Daniel

* src/uml_conf.c (VIR_FROM_THIS): Define to VIR_FROM_UML.
* src/xs_internal.c (VIR_FROM_THIS): Define to VIR_FROM_XEN.
* src/xml.c (VIR_FROM_THIS): Define to VIR_FROM_XML.
* src/stats_linux.c (VIR_FROM_THIS): Define to VIR_FROM_STATS_LINUX.
* src/datatypes.c (VIR_FROM_THIS): Define to VIR_FROM_NONE.
* src/lxc_conf.c (VIR_FROM_THIS): Define to VIR_FROM_LXC.
* src/libvirt.c (VIR_FROM_THIS): Define to VIR_FROM_NONE.
* src/node_device_conf.c (VIR_FROM_THIS): Define to VIR_FROM_NODEDEV.
* src/openvz_conf.c (VIR_FROM_THIS): Define to VIR_FROM_OPENVZ.
* src/openvz_driver.c (VIR_FROM_THIS): Define to VIR_FROM_OPENVZ.
* src/conf.c (VIR_FROM_THIS): Define to VIR_FROM_CONF.
Note: this loses config_filename:config_lineno diagnostics,
but that's ok.
* src/node_device.c (VIR_FROM_THIS): Define to VIR_FROM_NODEDEV.
* src/sexpr.c (VIR_FROM_THIS): Define to VIR_FROM_SEXPR.
* po/POTFILES.in: remove src/sexpr.c and src/lxc_conf.c