With my intended use of storage driver assist to chown files on remote
storage we will need a witness that will tell us whether the given
storage volume supports operations needed by the storage driver.

Gluster storage works on a similar principle to NFS where it takes the
uid and gid of the actual process and uses it to access the storage
volume on the remote server. This introduces a need to chown storage
files on gluster via native API.

My future work will modify the metadata crawler function to use the
storage driver file APIs to access the files instead of accessing them
directly so that we will be able to request the metadata for remote
files too. To avoid linking the storage driver to every helper file
using the utils code, the backing chain traversal function needs to be
moved to the storage driver source.

Additionally the virt-aa-helper and virstoragetest programs need to be
linked with the storage driver as a result of this change.

Add a storage driver API equivalent of the access() function.
Implementations for the filesystem and gluster backends are provided.

Different protocols have different means to uniquely identify a storage
file. This patch implements a storage driver API to retrieve a unique
string describing a volume. The current implementation works for local
storage only and returns the canonical path of the volume.

To add caching support the local filesystem driver now has a private
structure holding the cached string, which is created only when it's
initially accessed.

This patch provides the implementation for local files only for start.

Add storage driver based functions to access headers of storage files
for metadata extraction. Along with this patch a local filesystem and
gluster via libgfapi implementation is provided. The gluster
implementation is based on code of the saferead_lim function.

To allow using the storage driver APIs to access files on various
storage sources in a universal fashion possibly on storage such as nfs
with root squash we'll need to store the desired uid/gid in the
metadata.

Add new initialisation API that will store the desired uid/gid and a
wrapper for the current use. Additionally add docs for the two APIs.

Now that we store all metadata about a storage image in a
virStorageSource struct let's use it also to store information needed by
the storage driver to access and do operations on the files.

Now that storage source metadata is stored in a single struct we don't
need two initialization functions for different structs.

Continuing the refactoring of host-side storage descriptions out
of conf/domain_conf and into util/virstoragefile, this patch
focuses on details about a host name/port/transport as used by
a network storage volume.

* src/conf/domain_conf.h (virDomainDiskProtocolTransport)
(virDomainDiskHostDef, virDomainDiskHostDefClear)
(virDomainDiskHostDefFree, virDomainDiskHostDefCopy): Move...
* src/util/virstoragefile.h (virStorageNetHostTransport)
(virStorageNetHostDef, virStorageNetHostDefClear)
(virStorageNetHostDefFree, virStorageNetHostDefCopy): ...here,
with better names.
* src/util/virstoragefile.c (virStorageNetHostDefClear)
(virStorageNetHostDefFree, virStorageNetHostDefCopy): Moved from...
* src/conf/domain_conf.c (virDomainDiskHostDefClear)
(virDomainDiskHostDefFree, virDomainDiskHostDefCopy): ...here.
(virDomainDiskSourceDefClear, virDomainDiskSourceDefParse)
(virDomainDiskSourceDefFormatInternal): Adjust callers.
* src/conf/snapshot_conf.h (_virDomainSnapshotDiskDef): Likewise.
* src/conf/snapshot_conf.c (virDomainSnapshotDiskDefClear):
Likewise.
* src/qemu/qemu_command.c (qemuAddRBDHost)
(qemuParseDriveURIString, qemuParseNBDString)
(qemuBuildNetworkDriveURI, qemuParseCommandLineDisk)
(qemuParseCommandLine, qemuGetDriveSourceString): Likewise.
* src/qemu/qemu_command.h: Likewise.
* src/qemu/qemu_conf.c (qemuAddISCSIPoolSourceHost)
(qemuTranslateDiskSourcePool): Likewise.
* src/qemu/qemu_driver.c
(qemuDomainSnapshotCreateSingleDiskActive)
(qemuDomainSnapshotUndoSingleDiskActive): Likewise.
* src/storage/storage_backend_gluster.c
(virStorageFileBackendGlusterInit): Likewise.
* src/storage/storage_driver.c (virStorageFileFree)
(virStorageFileInitInternal): Likewise.
* src/storage/storage_driver.h (_virStorageFile): Likewise.
* src/libvirt_private.syms (domain_conf.h): Move symbols...
(virstoragefile.h): ...as appropriate.
Signed-off-by: NEric Blake <eblake@redhat.com>

Add APIs that will allow to use the storage driver to assist in
operations on files even for remote filesystems without native
representation as files in the host.

https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.

* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/;  If/.  If/

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

* global: patch created by running:
for f in $(git ls-files '*.[ch]') ; do
    cppi $f > $f.t && mv $f.t $f
done

* daemon/qemud.c, src/Makefile.am: Adapt for changed paths
* src/storage*.c, src/storage/*.h, src/parthelpre.c: Move
  to src/storage/

Done with these commands:
git grep -l Local.variab|xargs \
  perl -0x3b -pi -e 's,\n+/\*\n \* vim:(.|\n)*,\n,'

git grep -l Local.variab|xargs \
  perl -0x3b -pi -e 's,\n+/\*\n \* Local variables:\n(.|\n)*,\n,'

Use <config.h>, not "config.h", per autoconf documentation.
* Makefile.cfg (local-checks-to-skip) [sc_require_config_h]: Enable.
* .x-sc_require_config_h: New file, to list exempted files.
* Makefile.am (EXTRA_DIST): Add .x-sc_require_config_h.

	* src/bridge.c, src/bridge.h, src/qemu_conf.c, src/qemu_conf.h,
	  src/qemu_driver.c, src/qemu_driver.h, src/test.c: Disable more
	  of qemu if configured --without-qemu.

  stylesheet
* docs/*: regenerated
* src/bridge.c src/bridge.h src/buf.c src/iptables.c src/libvirt.c
  src/qemu_driver.c src/qemu_driver.h src/uuid.c src/uuid.h: cleanup,
  addd comments, made functions static and fixe a few bugs
Daniel

  src/sexpr.h src/test.c src/xm_internal.c src/xml.c src/xml.h:
  applied patch from Richard Jones adding check to printf-like
  functions and fixing the problems raised
Daniel

        * qemud/protocol.h: add the (domain/network)(Get/Set)Autostart
        requests and replies to the protocol.

        * src/qemu_internal.c: hookup the qemu driver autostart
        methods

        * qemud/dispatch.c, qemud/driver.[ch], internal.h: add
        the daemon side, but just set an in-memory autostart
        flag for now.

        * qemud/driver.[ch], qemud/dispatch.c: fix the fact that
        qemudDispatchDomainStart() doesn't report an error if the uuid
        lookup fails and also move the uuid lookup into the driver
        so that it matches the way we do Destroy().

        * include/libvirt/libvirt.h.in, src/libvirt.c: add
        virNetworkGetBridgeName() to allow finding out what
        bridge to connect to in order to join a network.

        * src/driver.h: add networkGetBridgeName() to vtable.

        * qemud/protocol.h: add the request and reply to
        the qemud protocol.

        * qemud/dispatch.c, qemud/driver.[ch]: handle them
        here.

        * src/qemu_internal.c: implement GetBridgeName()
        in the qemu driver.

        * src/libvirt_sym.version: add new symbol.

        * qemud/protocol.h: add the protocol for virtual networks

        * qemud/dispatch.c: implement the protocol

        * qemud/driver.[ch]: add stubs for the driver

        * qemud/internal.h: add struct qemud_network

        * src/qemu_internal.c: add a virtual networks driver