When user pass wrong root element, it is not 'internal error' and
we can give him hint what we are expecting.

Commit 498d7833 cleans up some of virtual file names for parsing strings
in memory. This patch cleans up (hopefuly) the rest forgotten by the
first patch.

This patch also changes all of the previously modified "filenames" to
valid URI's replacing spaces for underscores.

Changes to v1:
- Replace all spaces for underscores, so that the strings form valid
  URI's
- Replace spaces in places changed by commit 498d7833

And update callers to actually respect the error

We already have virAsprintf, so picking a similar name helps for
seeing a similar purpose.  Furthermore, the prefix V before printf
generally implies 'va_list', even though this variant was '...', and
the old name got in the way of adding a new va_list version.

global rename performed with:

$ git grep -l virBufferVSprintf \
  | xargs -L1 sed -i 's/virBufferVSprintf/virBufferAsprintf/g'

then revert the changes in ChangeLog-old.

And from all related macros and functions.

* cfg.mk (useless_free_options): Add many vir*Free* function names,
and then remove the useless if-before-free tests exposed by running
make syntax-check.
* src/conf/interface_conf.c (virInterfaceDefFree): Remove useless "if".
(virInterfaceAssignDef): Likewise.
* src/conf/network_conf.c (virNetworkAssignDef): Likewise.
* src/conf/storage_conf.c (virStoragePoolObjAssignDef): Likewise.
* src/node_device/node_device_hal.c (dev_create): Likewise.
* src/security/virt-aa-helper.c (vahDeinit): Likewise.
* src/test/test_driver.c (testNodeDeviceCreateXML): Likewise.
* src/util/conf.c (virConfSetValue): Likewise.

Prior to this patch, there was an inconsistent mix between GNU and C99.

For consistency, and potential portability to other compilers, stick
with the C99 vararg macro syntax.

* src/conf/cpu_conf.c (virCPUReportError): Use C99 rather than GNU
  vararg macro syntax.
* src/conf/domain_conf.c (virDomainReportError): Likewise.
* src/conf/domain_event.c (eventReportError): Likewise.
* src/conf/interface_conf.c (virInterfaceReportError): Likewise.
* src/conf/network_conf.c (virNetworkReportError): Likewise.
* src/conf/node_device_conf.h (virNodeDeviceReportError): Likewise.
* src/conf/secret_conf.h (virSecretReportError): Likewise.
* src/conf/storage_conf.h (virStorageReportError): Likewise.
* src/esx/esx_device_monitor.c (ESX_ERROR): Use C99 rather than
  GNU vararg macro syntax.
* src/esx/esx_driver.c (ESX_ERROR): Likewise.
* src/esx/esx_interface_driver.c (ESX_ERROR): Likewise.
* src/esx/esx_network_driver.c (ESX_ERROR): Likewise.
* src/esx/esx_secret_driver.c (ESX_ERROR): Likewise.
* src/esx/esx_storage_driver.c (ESX_ERROR): Likewise.
* src/esx/esx_util.c (ESX_ERROR): Likewise.
* src/esx/esx_vi.c (ESX_VI_ERROR): Likewise.
* src/esx/esx_vi_methods.c (ESX_VI_ERROR): Likewise.
* src/esx/esx_vi_types.c (ESX_VI_ERROR): Likewise.
* src/esx/esx_vmx.c (ESX_ERROR): Likewise.
* src/util/hostusb.c (usbReportError): Use C99 rather than GNU
  vararg macro syntax.
* src/util/json.c (virJSONError): Likewise.
* src/util/macvtap.c (ReportError): Likewise.
* src/util/pci.c (pciReportError): Likewise.
* src/util/stats_linux.c (virStatsError): Likewise.
* src/util/util.c (virUtilError): Likewise.
* src/util/xml.c (virXMLError): Likewise.
* src/xen/proxy_internal.c (virProxyError): Use C99 rather than
  GNU vararg macro syntax.
* src/xen/sexpr.c (virSexprError): Likewise.
* src/xen/xen_driver.c (xenUnifiedError): Likewise.
* src/xen/xen_hypervisor.c (virXenError): Likewise.
* src/xen/xen_inotify.c (virXenInotifyError): Likewise.
* src/xen/xend_internal.c (virXendError): Likewise.
* src/xen/xm_internal.c (xenXMError): Likewise.
* src/xen/xs_internal.c (virXenStoreError): Likewise.
* src/cpu/cpu.h (virCPUReportError): Use C99 rather than GNU
  vararg macro syntax.
* src/datatypes.c (virLibConnError): Likewise.
* src/interface/netcf_driver.c (interfaceReportError): Likewise.
* src/libvirt.c (virLibStreamError): Likewise.
* src/lxc/lxc_conf.h (lxcError): Likewise.
* src/network/bridge_driver.c (networkReportError): Likewise.
* src/nodeinfo.c (nodeReportError): Likewise.
* src/opennebula/one_conf.h (oneError): Likewise.
* src/openvz/openvz_conf.h (openvzError): Likewise.
* src/phyp/phyp_driver.c (PHYP_ERROR): Likewise.
* src/qemu/qemu_conf.h (qemuReportError): Likewise.
* src/remote/remote_driver.c (errorf): Likewise.
* src/security/security_driver.h (virSecurityReportError): Likewise.
* src/test/test_driver.c (testError): Likewise.
* src/uml/uml_conf.h (umlReportError): Likewise.
* src/vbox/vbox_driver.c (vboxError): Likewise.
* src/vbox/vbox_tmpl.c (vboxError): Likewise.

* src/conf/interface_conf.c (virInterfaceDefParseBond): Avoid dead stores
to local, "node".  Remove declaration, too.

The virConnectPtr is no longer required for error reporting since
that is recorded in a thread local. Remove use of virConnectPtr
from all APIs in interface_conf.{h,c} and update all callers to
match

It was used for error reporting only.

* src/conf/interface_conf.c (virInterfaceDefParseProtoIPv4): If
virXPathNodeSet returns -1, indicate failure by returning -1 right away.
(virInterfaceDefParseProtoIPv6): Likewise.

This was accomplished in xml parsing by doing away with the
stripped-down virInterfaceBareDef object, and just always using
virInterfaceDef, but with restrictions in certain places (eg, the type
of subordinate interface allowed in parsing depends on the parent
interface).

xml formatting was similarly adjusted. In addition, the formatting
functions keep track of the level of interface nesting, and insert
extra leading spaces on each line accordingly (using %*s).

The only change in formatted xml from previous (aside frmo supporting
new combinations of interface types) is that the subordinate ethernet
interfaces take up 2 lines rather than one, eg:

   <interface type='ethernet' name='eth0'>
   </interface>

instead of:

   <interface type='ethernet' name='eth0'/>

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.

* src/conf/interface_conf.c: the code was erronously returning -1
  in the two functions if <dhcp> is not provided

* src/conf/interface_conf.c: lack of one of these in the live xml output
  was causing the parse in virInterfaceDefParseBond() to fail

* src/conf/interface_conf.c: forgot to free the structure itself

This patch updates the xml parsing and formatting, and the associated
virInterfaceDef data structure to support IPv6, along the way adding
support for multiple protocols per interface, and multiple IP
addresses per protocol.
* src/conf/interface_conf.[ch]: update the structures, code for parsing
  and serialization

This patch adds the flag VIR_INTERFACE_XML_INACTIVE to
virInterfaceGetXMLDesc's flags. When it is*not* set (the default), the
live interface info will be returned in the XML (in particular, the IP
address(es) and netmask(s) will be retrieved by querying the interface
directly, rather than  reporting what's in the config file). The
backend of this is in netcf's ncf_if_xml_state() function.

* configure.in libvirt.spec.in: requires netcf >= 0.1.3
* include/libvirt/libvirt.h.in: adds flag VIR_INTERFACE_XML_INACTIVE
* src/conf/interface_conf.c src/interface/netcf_driver.c src/libvirt.c:
  update the parsing and backend routines accordingly
* tools/virsh.c: change interface edit to inactive definition and
  adds the inactive flag for interface dump

The minimal XML returned from ncf_if_xml_state() doesn't contain this
attribute (which makes no sense in the case of reporting current
status of the interface), and it was preventing it from passing
through the parse/format step.

* src/conf/interface_conf.[ch]: add a new virInterfaceStartMode value
  and modify loading/saving accordingly

* src/conf/interface_conf.c: This was causing subsequent calls to
  virXPathxxx() to fail, since ctxt->node was left pointing at the
  dhcp node, rather than the protocol node.

* 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/interface_conf.c (virInterfaceDefParseDhcp): Remove unused "old".

* src/datatypes.c src/domain_conf.c src/interface_conf.c
  src/lxc_driver.c src/qemu_driver.c src/storage_backend.c src/virsh.c:
  add bare %s format string to printf-derivatives called with no format
  string

* qemud/remote.c src/interface_conf.[ch] src/veth.[ch]: more renaming
  from interface to iface

* interface_conf.c interface_conf.h: utilities function usful for
  interface driver like the test interface driver

* src/interface_conf.c src/interface_conf.h: the import and export
  routines and the internal APIs
* src/Makefile.am: hook the new file in the makefiles
* src/libvirt_private.syms: export a few private symbols internally
* po/POTFILES.in: the new file contains translatable strings