This flag is intended to allow user to do so called system reset
after dump, instead of sending ACPI reboot event.

Counterpart to --roots.

* include/libvirt/libvirt.h.in (VIR_DOMAIN_SNAPSHOT_LIST_LEAVES):
New flag.
* src/libvirt.c (virDomainSnapshotNum, virDomainSnapshotListNames)
(virDomainSnapshotNumChildren)
(virDomainSnapshotListChildrenNames): Document it.
* tools/virsh.c (cmdSnapshotList): Expose it.
* tools/virsh.pod (snapshot-list): Document --leaves.

The previous API addition allowed traversal up the hierarchy;
this one makes it easier to traverse down the hierarchy.

In the python bindings, virDomainSnapshotNumChildren can be
generated, but virDomainSnapshotListChildrenNames had to copy
from the hand-written example of virDomainSnapshotListNames.

* include/libvirt/libvirt.h.in (virDomainSnapshotNumChildren)
(virDomainSnapshotListChildrenNames): New prototypes.
(VIR_DOMAIN_SNAPSHOT_LIST_DESCENDANTS): New flag alias.
* src/libvirt.c (virDomainSnapshotNumChildren)
(virDomainSnapshotListChildrenNames): New functions.
* src/libvirt_public.syms: Export them.
* src/driver.h (virDrvDomainSnapshotNumChildren)
(virDrvDomainSnapshotListChildrenNames): New callbacks.
* python/generator.py (skip_impl, nameFixup): Update lists.
* python/libvirt-override-api.xml: Likewise.
* python/libvirt-override.c
(libvirt_virDomainSnapshotListChildrenNames): New wrapper function.

Although reverting to a snapshot is a form of data loss, this is
normally expected.  However, there are two cases where additional
surprises (failure to run the reverted state, or a break in
connectivity to the domain) can come into play.  Requiring extra
acknowledgment in these cases will make it less likely that
someone can get into an unrecoverable state due to a default revert.

Also create a new error code, so users can distinguish when forcing
would make a difference, rather than having to blindly request force.

* include/libvirt/libvirt.h.in (VIR_DOMAIN_SNAPSHOT_REVERT_FORCE):
New flag.
* src/libvirt.c (virDomainRevertToSnapshot): Document it.
* include/libvirt/virterror.h (VIR_ERR_SNAPSHOT_REVERT_RISKY): New
error value.
* src/util/virterror.c (virErrorMsg): Implement it.
* tools/virsh.c (cmdDomainSnapshotRevert): Add --force to virsh.
* tools/virsh.pod (snapshot-revert): Document it.

Add new public api for 'reset'.
It can reset domain immediately without any guest shutdown.
Signed-off-by: NXu He Jie <xuhj@linux.vnet.ibm.com>

Although a client can already obtain a snapshot's parent by
dumping and parsing the xml, then doing a snapshot lookup by
name, it is more efficient to get the parent in one step, which
in turn will make operations that must traverse a snapshot
hierarchy easier to perform.

* include/libvirt/libvirt.h.in (virDomainSnapshotGetParent):
Declare.
* src/libvirt.c (virDomainSnapshotGetParent): New function.
* src/libvirt_public.syms: Export it.
* src/driver.h (virDrvDomainSnapshotGetParent): New callback.

/usr/lib/stdlib.h in Mac OS X and probably also in BSD's
exports this symbol :(

Documentation did not specify, that some permissions are required on
target path for coredump for the user running the hypervisor.

Diff to v1:
- reword statements

These functions access internals of the opaque object, and do
not need any rpc counterpart.  It could be argued that we should
have provided these when snapshot objects were first introduced,
since all the other vir*Ptr objects have at least a GetName accessor.

* include/libvirt/libvirt.h.in (virDomainSnapshotGetName)
(virDomainSnapshotGetDomain, virDomainSnapshotGetConnect): Declare.
* src/libvirt.c (virDomainSnapshotGetName)
(virDomainSnapshotGetDomain, virDomainSnapshotGetConnect): New
functions.
* src/libvirt_public.syms: Export them.

Prior to this patch, <domainsnapshot>/<disks> was ignored.  This
changes it to be an error unless an explicit disk snapshot is
requested (a future patch may relax things if it turns out to
be useful to have a <disks> specification alongside a system
checkpoint).

* include/libvirt/libvirt.h.in
(VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY): New flag.
* src/libvirt.c (virDomainSnapshotCreateXML): Document it.
* src/esx/esx_driver.c (esxDomainSnapshotCreateXML): Disk
snapshots not supported yet.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotCreateXML): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML): Likewise.

Since a snapshot is fully recoverable, it is useful to have a
snapshot as a means of hibernating a guest, then reverting to
the snapshot to wake the guest up.  This mode of usage is
similar to 'virsh save/virsh restore', except that virsh
save uses an external file while virsh snapshot keeps the
vm state internal to a qcow2 file.  However, it only works on
persistent domains.

In the usage pattern of snapshot/revert for hibernating a guest,
there is no need to keep the guest running between the two points
in time, especially since that would generate runtime state that
would just be discarded.  Add a flag to make it possible to
stop the domain after the snapshot has completed.

* include/libvirt/libvirt.h.in (VIR_DOMAIN_SNAPSHOT_CREATE_HALT):
New flag.
* src/libvirt.c (virDomainSnapshotCreateXML): Document it.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML)
(qemuDomainSnapshotCreateActive): Implement it.

Reverting to a state prior to an external snapshot risks
corrupting any other branches in the snapshot hierarchy that
were using the snapshot as a read-only backing file.  So
disk snapshot code will default to preventing reverting to
a snapshot that has any children, meaning that deleting just
the children of a snapshot becomes a useful operation in
preparing that snapshot for being a future reversion target.
The code for the new flag is simple - it's one less deletion,
plus a tweak to keep the current snapshot correct.

* include/libvirt/libvirt.h.in
(VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY): New flag.
* src/libvirt.c (virDomainSnapshotDelete): Document it, and
enforce mutual exclusion.
* src/qemu/qemu_driver.c (qemuDomainSnapshotDelete): Implement
it.

Just like VM saved state images (virsh save), snapshots MUST
track the inactive domain xml to detect any ABI incompatibilities.

The indentation is not perfect, but functionality comes before form.

Later patches will actually supply a full domain; for now, this
wires up the storage to support one, but doesn't ever generate one
in dumpxml output.

Happily, libvirt.c was already rejecting use of VIR_DOMAIN_XML_SECURE
from read-only connections, even though before this patch, there was
no information to be secured by the use of that flag.

And while we're at it, mark the libvirt snapshot metadata files
as internal-use only.

* src/libvirt.c (virDomainSnapshotGetXMLDesc): Document flag.
* src/conf/domain_conf.h (_virDomainSnapshotDef): Add member.
(virDomainSnapshotDefParseString, virDomainSnapshotDefFormat):
Update signature.
* src/conf/domain_conf.c (virDomainSnapshotDefFree): Clean up.
(virDomainSnapshotDefParseString): Optionally parse domain.
(virDomainSnapshotDefFormat): Output full domain.
* src/esx/esx_driver.c (esxDomainSnapshotCreateXML)
(esxDomainSnapshotGetXMLDesc): Update callers.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotCreateXML)
(vboxDomainSnapshotGetXMLDesc): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML)
(qemuDomainSnapshotLoad, qemuDomainSnapshotGetXMLDesc)
(qemuDomainSnapshotWriteMetadata): Likewise.
* docs/formatsnapshot.html.in: Rework doc example.
Based on a patch by Philipp Hahn.

Just as leaving managed save metadata behind can cause problems
when creating a new domain that happens to collide with the name
of the just-deleted domain, the same is true of leaving any
snapshot metadata behind.  For safety sake, extend the semantic
change of commit b26a9fa9 to also cover snapshot metadata as a
reason to reject undefining an inactive domain.  A future patch
will make sure that shutdown of a transient domain automatically
deletes snapshot metadata (whether by destroy, shutdown, or
guest-initiated action).  Management apps of transient domains
should take care to capture xml of snapshots, if it is necessary
to recreate the snapshot metadata on a later transient domain
with the same name and uuid.

This also documents a new flag that hypervisors can choose to
support as a shortcut for taking care of the metadata as part of
the undefine process; however, nontrivial driver support for these
flags will be deferred to future patches.

Note that ESX and VBox can never be transient; therefore, they
do not have to worry about automatic cleanup after shutdown
(the persistent domain still remains); likewise they never
store snapshot metadata, so the undefine flag is trivial.
The nontrivial work remaining is thus in the qemu driver.

* include/libvirt/libvirt.h.in
(VIR_DOMAIN_UNDEFINE_SNAPSHOTS_METADATA): New flag.
* src/libvirt.c (virDomainUndefine, virDomainUndefineFlags):
Document new limitations and flag.
* src/esx/esx_driver.c (esxDomainUndefineFlags): Trivial
implementation.
* src/vbox/vbox_tmpl.c (vboxDomainUndefineFlags): Likewise.
* src/qemu/qemu_driver.c (qemuDomainUndefineFlags): Enforce
the limitations.

The first two flags are essential for being able to replicate
snapshot hierarchies across multiple hosts, which will come in
handy for supervised migrations.  It also allows a management app
to take a snapshot of a transient domain, save the metadata, stop
the domain, recreate a new transient domain by the same name,
redefine the snapshot, then revert to it.

This is not quite as convenient as leaving the metadata behind
after a domain is no longer around, but doing that has a few
problems: 1. the libvirt API can only delete snapshot metadata
if there is a valid domain handle to use to get to that snapshot
object - if stale data is left behind without a domain, there is
no way to request that the data be cleaned up. 2. creating a new
domain with the same name but different uuid than the older
domain where a snapshot existed cannot use the older snapshot
data; this risks confusing libvirt, and forbidding the stale
data is similar to the recent patch to forbid stale managed save.

The first two flags might be useful on hypervisors with no metadata,
but only for modifying the notion of the current snapshot;
however, I don't know how to do that for ESX or VBox.

The third flag is a convenience option, to combine a creation with
a delete metadata into one step.  It is trivial for hypervisors
with no metadata.

The qemu changes will be involved enough to warrant a separate patch.

* include/libvirt/libvirt.h.in
(VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE)
(VIR_DOMAIN_SNAPSHOT_CREATE_CURRENT)
(VIR_DOMAIN_SNAPSHOT_CREATE_NO_METADATA): New flags.
* src/libvirt.c (virDomainSnapshotCreateXML): Document them, and
enforce mutual exclusion.
* src/esx/esx_driver.c (esxDomainSnapshotCreateXML): Trivial
implementation.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotCreateXML): Likewise.
* docs/formatsnapshot.html.in: Document re-creation.

To make it easier to know when undefine will fail because of existing
snapshot metadata, we need to know how many snapshots have metadata.

Also, it is handy to filter the list of snapshots to just those that
have no parents; document that flag now, but implement it in later patches.

* include/libvirt/libvirt.h.in (VIR_DOMAIN_SNAPSHOT_LIST_ROOTS)
(VIR_DOMAIN_SNAPSHOT_LIST_METADATA): New flags.
* src/libvirt.c (virDomainSnapshotNum)
(virDomainSnapshotListNames): Document them.
* src/esx/esx_driver.c (esxDomainSnapshotNum)
(esxDomainSnapshotListNames): Implement trivial flag.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotNum)
(vboxDomainSnapshotListNames): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSnapshotNum)
(qemuDomainSnapshotListNames): Likewise.

A future patch will make it impossible to remove a domain if it
would leave behind any libvirt-tracked metadata about snapshots,
since stale metadata interferes with a new domain by the same name.
But requiring snaphot contents to be deleted before removing a
domain is harsh; with qemu, qemu-img can still make use of the
contents after the libvirt domain is gone.  Therefore, we need
an option to get rid of libvirt tracking information, but not
the actual contents.  For hypervisors that do not track any
metadata in libvirt, the implementation is trivial; all remaining
hypervisors (really, just qemu) will be dealt with separately.

* include/libvirt/libvirt.h.in
(VIR_DOMAIN_SNAPSHOT_DELETE_METADATA_ONLY): New flag.
* src/libvirt.c (virDomainSnapshotDelete): Document it.
* src/esx/esx_driver.c (esxDomainSnapshotDelete): Trivially
supported when there is no libvirt metadata.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotDelete): Likewise.

While it is nice that snapshots and saved images remember whether
the domain was running or paused, sometimes the restoration phase
wants to guarantee a particular state (paused to allow hot-plugging,
or running without needing to call resume).  This introduces new
flags to allow the control, and a later patch will implement the
flags for qemu.

* include/libvirt/libvirt.h.in (VIR_DOMAIN_SAVE_RUNNING)
(VIR_DOMAIN_SAVE_PAUSED, VIR_DOMAIN_SNAPSHOT_REVERT_RUNNING)
(VIR_DOMAIN_SNAPSHOT_REVERT_PAUSED): New flags.
* src/libvirt.c (virDomainSaveFlags, virDomainRestoreFlags)
(virDomainManagedSave, virDomainSaveImageDefineXML)
(virDomainRevertToSnapshot): Document their use, and enforce
mutual exclusion.

This patch adds the ability to make the filesystem for a filesystem
pool during a pool build.

The patch adds two new flags, no overwrite and overwrite, to control
when mkfs gets executed.  By default, the patch preserves the
current behavior, i.e., if no flags are specified, pool build on a
filesystem pool only makes the directory on which the filesystem
will be mounted.

If the no overwrite flag is specified, the target device is checked
to determine if a filesystem of the type specified in the pool is
present.  If a filesystem of that type is already present, mkfs is
not executed and the build call returns an error.  Otherwise, mkfs
is executed and any data present on the device is overwritten.

If the overwrite flag is specified, mkfs is always executed, and any
existing data on the target device is overwritten unconditionally.

There is a goto before "conn" is initialized.

Includes impl of python binding since the generator was not
able to cope.

Note: Requires gendispatch.pl patch from Matthias Bolte

https://www.redhat.com/archives/libvir-list/2011-August/msg01367.html

There is no reason to forbid pausing an autodestroy domain
(not to mention that 'virsh start --paused --autodestroy'
succeeds in creating a paused autodestroy domain).

Meanwhile, qemu was failing to enforce the API documentation that
autodestroy domains cannot be saved.  And while the original
documentation only mentioned save/restore, snapshots are another
form of saving that are close enough in semantics as to make no
sense on one-shot domains.

* src/qemu/qemu_driver.c (qemudDomainSuspend): Drop bogus check.
(qemuDomainSaveInternal, qemuDomainSnapshotCreateXML): Forbid
saves of autodestroy domains.
* src/libvirt.c (virDomainCreateWithFlags, virDomainCreateXML):
Document snapshot interaction.

There have been several instances of people having problems with
a broken managed save file, and not aware that they could use
'virsh managedsave-remove dom' to fix things.  Making it possible
to do this as part of starting a domain makes the same functionality
easier to find, and one less API call.

* include/libvirt/libvirt.h.in (VIR_DOMAIN_START_FORCE_BOOT): New
flag.
* src/libvirt.c (virDomainCreateWithFlags): Document it.
* src/qemu/qemu_driver.c (qemuDomainObjStart): Alter signature.
(qemuAutostartDomain, qemuDomainStartWithFlags): Update callers.
* tools/virsh.c (cmdStart): Expose it in virsh.
* tools/virsh.pod (start): Document it.

* docs/drvqemu.html.in: Fix typo.
* src/libvirt.c (virDomainCreateXML, virDomainCreateWithFlags):
Likewise.

When virStreamAbort is called on a stream that has not been used yet,
quite confusing error is returned: "this function is not supported by
the connection driver". Let's just ignore such streams as there's
nothing to abort anyway.

If migration failed on source daemon, the migration is automatically
canceled by the daemon itself. Thus we don't need to call
virDomainMigrateConfirm3(cancelled=1). Calling it doesn't cause any harm
but the resulting error message printed in logs may confuse people.

* src/qemu/qemu_migration.c: avoid dead 'ret' assignment and silence
  clang warning.

Detected by ccc-analyzer:

libvirt.c:4277:5: warning: Value stored to 'ret' is never read
    ret = domain->conn->driver->domainMigrateConfirm3
    ^     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

My previous patch 74c75671
introduced a regression by removing TLS initialization from client.

I was testing a virsh patch, and wanted to see if I had passed the
flags I thought.  But with LIBVIRT_DEBUG in the environment, I just
saw:

14:24:52.359: 15022: debug : virDomainSnapshotNum:15586 : dom=0xc9c180, (VM: name=rhel_6-64, uuid=48f8e8e7-e14f-0e14-02f0-ce71997bdcab),

including a trailing space.  This fixes the issues.

* src/libvirt.c: Log flag parameters, even if currently unused.
(VIR_DOMAIN_DEBUG_0): Drop trailing comma in log.
(VIR_DOMAIN_DEBUG_1): Split guts into...
(VIR_DOMAIN_DEBUG_2): ...new macro.

Transient domains reject attempts to set autostart, and using
virDomainCreate to restart a domain only works on persistent
domains.  Therefore, managed save makes no sense on transient
domains, and should be rejected up front rather than creating
an otherwise unrecoverable managed save file.

Besides, transient domains imply that a lot more management is
being done by the upper layer; this includes the assumption
that the upper layer is okay managing the saved state file
created by virDomainSave, and does not need to use managed save.

* src/libvirt.c: Document that transient domains are incompatible
with managed save.
* src/qemu/qemu_driver.c (qemuDomainManagedSave): Enforce it.
* src/libxl/libxl_driver.c (libxlDomainManagedSave): Likewise.

src/libvirt.c: "may requires" is confusing; the s was extra.

Because we do support flags for virDomainSetBlkioParameters and
virDomainGetBlkioParameters, update appropriate description as well.

* tools/virsh.c: avoid memory leak in cmdVolPath.
* src/libvirt.c: Add doc for virStorageVolGetPath to tell one
  must free() the returned path after use.

* how to reproduce?

% dd if=/dev/zero of=/var/lib/libvirt/images/foo.img count=1 bs=10M
% virsh pool-refresh default
% valgrind -v --leak-check=full virsh vol-path --vol \
/var/lib/libvirt/images/foo.img

* actual results:

Detected in valgrind run:

==16436== 32 bytes in 1 blocks are definitely lost in loss record 7 of 22
==16436==    at 0x4A05FDE: malloc (vg_replace_malloc.c:236)
==16436==    by 0x386A314B3D: xdr_string (in /lib64/libc-2.12.so)
==16436==    by 0x3DF8CD770D: xdr_remote_nonnull_string (remote_protocol.c:3
==16436==    by 0x3DF8CD7EC8: xdr_remote_storage_vol_get_path_ret
% virsh pool-refresh default
% valgrind -v --leak-check=full virsh vol-path --vol \
/var/lib/libvirt/images/foo.img
Signed-off-by: NAlex Jia <ajia@redhat.com>

Make MIGRATION_OUT use the new helper methods.

This also introduces new protection to migration v3 process: the
migration job is held from Begin to Confirm to avoid changes to a domain
during migration (esp. between Begin and Perform phases). This change is
automatically applied to p2p and tunneled migrations. For normal
migration, this requires support from a client. In other words, if an
old (pre 0.9.4) client starts normal migration of a domain, the domain
will not be protected against changes between Begin and Perform steps.

Now that virDomainSetVcpusFlags knows about VIR_DOMAIN_AFFECT_CURRENT,
so should virDomainGetVcpusFlags.

Unfortunately, the virsh counterpart 'virsh vcpucount' has already
commandeered --current for a different meaning, so teaching virsh
to expose this in the next patch will require a bit of care.

* src/libvirt.c (virDomainGetVcpusFlags): Allow
VIR_DOMAIN_AFFECT_CURRENT.
* src/libxl/libxl_driver.c (libxlDomainGetVcpusFlags): Likewise.
* src/qemu/qemu_driver.c (qemudDomainGetVcpusFlags): Likewise.
* src/test/test_driver.c (testDomainGetVcpusFlags): Likewise.
* src/xen/xen_driver.c (xenUnifiedDomainGetVcpusFlags): Likewise.

* src/libvirt.c: implement the main entry points

Modifying the xml on either save or restore only gets you so
far - you have to remember to 'virsh dumpxml dom' just prior
to the 'virsh save' in order to have an xml file worth modifying
that won't be rejected due to abi breaks.  To make this more
powerful, we need a way to grab the xml embedded within a state
file, and from there, it's not much harder to also support
modifying a state file in-place.

Also, virDomainGetXMLDesc didn't document its flags.

* include/libvirt/libvirt.h.in (virDomainSaveImageGetXMLDesc)
(virDomainSaveImageDefineXML): New prototypes.
* src/libvirt.c (virDomainSaveImageGetXMLDesc)
(virDomainSaveImageDefineXML): New API.
* src/libvirt_public.syms: Export them.
* src/driver.h (virDrvDomainSaveImageGetXMLDesc)
(virDrvDomainSaveImgeDefineXML): New driver callbacks.