There is a little easter egg in virsh: one can easily clone
an object (domain, network, ...). Just 'virsh edit' change the name
and remove <uuid>. And then, in the end when reporting success
the new name was printed out.
However, with recent edit rewrite we lost the final part and are
still printing the original name out.

When printing reedit options we make stdin raw. However,
this results in stdout being raw as well. Therefore we need
to return carriage when doing new line. Unfortunately,
'\r' cannot be part of internationalized messages hence
we must move them to formatting string which then in turn
become huge and disarranged. To solve this, a new function
is introduced which takes variable string arguments and
prepend each with "\r\n" just before printing.

While unescaping the commands the commands passed through to the monitor
function qemuMonitorUnescapeArg() initialized lenght of the input string
to strlen()+1 which is fine for alloc but not for iteration of the
string.

This patch fixes the off-by-one error and drops the pointless check for
a single trailing slash that is automaticaly handled by the default
branch of switch.

The attach-disk command used with parameter --cache created an invalid
XML snippet as the beginning of the <driver> element was not printed
when used solely with --cache and no other attribute to driver.

commit 52d064f4 added
VIR_NETWORK_XML_INACTIVE in order to allow suppressing the
auto-generated list of VFs in network definitions, and a --inactive
flag to virsh net-dumpxml to take advantage of the flag. However, it
missed out on two opportunities:

1) Use INACTIVE to get the current config of the network as it
   exists on disk, rather than the currently active config.

2) Add INACTIVE to the flags used for the virsh net-edit command, so
   that it won't include the forward-pool interfaces that were
   autogenerated, and so that a re-edit of the network prior to
   restarting it will show any other edits made since the last restart
   of the network. (prior to this patch, if you edited a network a 2nd
   time without restarting, all of the previous edits would magically
   disappear).

In order to fit with the new #define-based generic edit function in
virsh.c, a new function vshNetworkGetXMLDesc() was added. This
function first tries to call virNetworkGetXMLDesc with the INACTIVE
flag added, then retries without if the first attempt fails (in the
manner expected when the server doesn't support it).

A core use case of the hook scripts is to be able to do things
to a guest's network configuration. It is possible to hook into
the 'start' operation for a QEMU guest which runs just before
the guest is started. The TAP devices will exist at this point,
but the QEMU process will not. It can be desirable to have a
'started' hook too, which runs once QEMU has started.

If libvirtd is restarted it will re-populate firewall rules,
but there is no QEMU hook to trigger for existing domains.
This is solved with a 'reconnect' hook.

Finally, if attaching to an external QEMU process there needs
to be an 'attach' hook script.

This all also applies to the LXC driver

* docs/hooks.html.in: Document new operations
* src/util/hooks.c, src/util/hooks.c: Add 'started', 'reconnect'
  and 'attach' operations for QEMU. Add 'prepare', 'started',
  'release' and 'reconnect' operations for LXC
* src/lxc/lxc_driver.c: Add hooks for 'prepare', 'started',
  'release' and 'reconnect' operations
* src/qemu/qemu_process.c: Add hooks for 'started', 'reconnect'
  and 'reconnect' operations

First 'poll' can't return EWOULDBLOCK, and second, we're checking errno
so far away from the poll() call that we've probably already trashed the
original errno value.

In addition to keepalive responses, we also need to send keepalive
requests from client IO loop to properly detect dead connection in case
a libvirt API is called from the main loop, which prevents any timers to
be called.

We don't need to add or remove filters when client object is already
locked anymore. There's no reason to keep the *Locked variants of those
APIs.

The previous commit removed the only usage of ``all'' parameter in
virKeepAliveStopInternal, which was actually the only reason for having
virKeepAliveStopInternal. This effectively reverts most of commit
6446a9e2.

When a libvirt API is called from the main event loop (which seems to be
common in event-based glib apps), the client IO loop would properly
handle keepalive requests sent by a server but will not actually send
them because the main event loop is blocked with the API. This patch
gets rid of response timer and the thread which is processing keepalive
requests is also responsible for queueing responses for delivery.

This makes it possible to create and queue new calls while we are
running IO loop.

Add virKeepAliveTimeout and virKeepAliveTrigger APIs that can be used to
set poll timeouts and trigger keepalive timer. virKeepAliveTrigger
checks if it is called to early and does nothing in that case.

The code that needs to be run every keepalive interval of inactivity was
only called from a timer and thus from the main event loop. We will need
to call the code directly from another place.

As we never drop non-blocking calls, the return value that used to
indicate a call was dropped is no longer needed.

As non-blocking calls are no longer dropped, we don't really need to
care that much about their fate and wait for the thread with the buck
to process them. If another thread has the buck, we can just push a
non-blocking call to the queue and be done with it.

So far, we were dropping non-blocking calls whenever sending them would
block. In case a client is sending lots of stream calls (which are not
supposed to generate any reply), the assumption that having other calls
in a queue is sufficient to get a reply from the server doesn't work. I
tried to fix this in b1e374a7 but
failed and reverted that commit.

With this patch, non-blocking calls are never dropped (unless the
connection is being closed) and will always be sent.

Normally, when every call has a thread associated with it, the thread
may get the buck and be in charge of sending all calls until its own
call is done. When we introduced non-blocking calls, we had to add
special handling of new non-blocking calls. This patch uses event loop
to send data if there is no thread to get the buck so that any
non-blocking calls left in the queue are properly sent without having to
handle them specially. It also avoids adding even more cruft to client
IO loop in the following patches.

With this change in, non-blocking calls may see unpredictable delays in
delivery when the client has no event loop registered. However, the only
non-blocking calls we have are keepalives and we already require event
loop for them, which makes this a non-issue until someone introduces new
non-blocking calls.

When analyzing our debug log, I'm always confused about what each of the
pointers mean. Let's be explicit.

'make dist' was depending on *protocol-structs files, which are
stored in git but in turn depended on generated files.  We still
want to ship the protocol-structs files, but by renaming the
tests to something not matching a file name, we separate 'make
check' (which depends on the generated file) from 'make dist'
(which only depends on the git files).  After all, the tarball
should never depend on a generated file not stored in git.

I found one more case of a git file depending on a generated
file, in a bogus virkeycode.c listing; but at least this one
had no associated rules so it never broke 'make dist'.

Reported by Wen Congyang.  Latent bug has been present since
commit 62dee6fa, but only recently exposed by commit 7bff56a0.

* src/Makefile.am ($(srcdir)/util/virkeycode.c): Drop useless
dependency.
(BUILT_SOURCES): ...and build virkeymaps.h sooner.
(PROTOCOL_STRUCTS): Rather than depend on the struct file...
(check-local): ...convert things into a phony target of...
(check-protocol): ...a new check.
($(srcdir)/remote_protocol-struct): Rename to isolate the distributed
file from the conditional test.
(PDWTAGS): Deal with rename.  Swap to compare 'expected actual'.

Otherwise, 'make dist' gives multiple warnings like:

libvirt.pot:20814: warning: internationalized messages should not contain the `\r' escape sequence

* tools/virsh.c (vshAskReedit): Avoid \r in _().

so we can update file system quota

with persist=false the domain config file will not be updated.

for containers matching virDomainDiskIndexByName.

libvirt.spec.in: s/{?rhel}/%{?rhel}/

Python exceptions are different than libvirt errors, and we had
some corner case bugs on OOM situations.

* python/libvirt-override.c (libvirt_virDomainSnapshotListNames)
(libvirt_virDomainSnapshotListChildrenNames): Use correct error
returns, avoid segv on OOM, and avoid memory leaks on error.

* python/libvirt-override.c (libvirt_virDomainGetVcpus)
(libvirt_virDomainGetVcpuPinInfo): Use Py_XDECREF instead of
open-coding it.

Currently, if qemuProcessStart fail at some point, e.g. because
domain being started wants a PCI/USB device already assigned to
a different domain, we jump to cleanup label where qemuProcessStop
is performed. This unconditionally calls virSecurityManagerRestoreAllLabel
which is wrong because the other domain is still using those devices.

However, once we successfully label all devices/paths in
qemuProcessStart() from that point on, we have to perform a rollback
on failure - that is - we have to virSecurityManagerRestoreAllLabel.

Currently, we are passing only one boolean (migrated) so there is
no real profit in this. But it creates starting position for
next patch.

The two APIs are rather trivial; based on bits and pieces of other
existing APIs.  It leaves the door open for future extension to
qemu to report snapshots without metadata based on reading qcow2
internal snapshot names.

* src/qemu/qemu_driver.c (qemuDomainSnapshotIsCurrent)
(qemuDomainSnapshotHasMetadata): New functions.

A few examples for <interface> had a type='direct' interface with no
sub-elements. This is not allowed - a type='direct' interface must
have at least a source element. (Most likely the example was copied
from the type='user' or type='ethernet' examples - they *do* allow an
instance with no sub-elements).

There was also one place that mistakenly used %lt; ... %gt; instead of
&lt; ... &gt; (for some reason, I make that typo all the time).

Pretty straightforward.

* src/remote/remote_protocol.x
(remote_domain_snapshot_is_current_args)
(remote_domain_snapshot_is_current_ret)
(remote_domain_snapshot_has_metadata_args)
(remote_domain_snapshot_has_metadata_ret): New structs.
(REMOTE_PROC_DOMAIN_SNAPSHOT_IS_CURRENT)
(REMOTE_PROC_DOMAIN_SNAPSHOT_HAS_METADATA): New RPC calls.
* src/remote/remote_driver.c (remote_driver): Call them.
* src/remote_protocol-structs: Regenerate.

Expose the recent API additions in virsh.  Borrows ideas from 'dominfo'
for the general type of information to display.

Output looks like:

$ tools/virsh snapshot-info fedora-local tmp
Name:           tmp
Domain:         fedora-local
Current:        no
State:          disk-snapshot
Parent:         -
Children:       1
Descendants:    2
Metadata:       yes

possibly with fewer lines when talking to older servers.

* tools/virsh.c (cmdSnapshotInfo): New command.
* tools/virsh.pod (snapshot-info): Document it.

Eric Blake and Guido Günther were guests during this week's
FLOSS Weekly podcast, giving insights into libvirt as a Free
Software project.  Also, there are several useful blogs on
virt-related topics.

* docs/relatedlinks.html.in (Blogs and Podcasts): New section.

Ensure systemd is used in RHEL-7 and cgconfig is not used in
RHEL-7

Right now, starting from just a virDomainSnapshotPtr, and wanting to
know if it is the current snapshot for its respective domain, you have
to use virDomainSnapshotGetDomain(), then virDomainSnapshotCurrent(),
then compare the two names returned by virDomainSnapshotGetName().
It is a bit easier if we can directly query this information from the
snapshot itself.

Right now, it is possible to filter a snapshot listing based on
whether snapshots have metadata that would prevent domain deletion,
but the only way to learn if an individual snapshot has metadata is
to see if that snapshot appears in the list returned by a listing.
Additionally, I hope to expand the qemu driver in a future patch to
use qemu-img to reconstruct snapshot XML corresponding to internal
qcow2 snapshot names not otherwise tracked by libvirt (in part, so
that libvirt can guarantee that new snapshots are not created with
a name that would silently corrupt the existing portion of the qcow2
file); if I ever get that in, then it would no longer be an all-or-none
decision on whether snapshots have metadata, and becomes all the more
important to be able to directly determine that information from a
particular snapshot.

Other query functions (such as virDomainIsActive) do not have a flags
argument, but since virDomainHasCurrentSnapshot takes a flags argument,
I figured it was safer to provide a flags argument here as well.

* include/libvirt/libvirt.h.in (virDomainSnapshotIsCurrent)
(virDomainSnapshotHasMetadata): New declarations.
* src/libvirt.c (virDomainSnapshotIsCurrent)
(virDomainSnapshotHasMetadata): New functions.
* src/libvirt_public.syms (LIBVIRT_0.9.13): Export them.
* src/driver.h (virDrvDomainSnapshotIsCurrent)
(virDrvDomainSnapshotHasMetadata): New driver callbacks.

No semantic change; this will make it easier to refactor code.

* tools/virsh.c (cmdSnapshotList): Drop level of indentation, and
rename a variable.

Requiring the user to pass in parallel arrays of names and parents
is annoying; it means that you can't qsort one of the arrays without
invalidating the ordering of the other.  By refactoring this function
to use callbacks, we isolate the layout to be independent of the
printing, and a future patch can exploit that to improve layout.

* tools/virsh.c (vshTreePrintInternal): Use callbacks rather than
requiring a char** array.
(vshTreeArrayLookup): New helper function.
(vshTreePrint, cmdNodeListDevices, cmdSnapshotList): Update callers.

I am not a fan of fixed-width buffers.  All it takes is a
linear chain of more than 100 snapshots to mess up 'virsh
snapshot-list --tree'.  Now that virBuffer is more powerful,
we might as well exploit its power.

* tools/virsh.c (cmdNodeListDevicesPrint): Simplify to use a
virBuffer instead of fixed-width prefix, factor guts, and rename...
(vshTreePrint, vshTreePrintInternal): ...along with new helper.
(cmdNodeListDevices, cmdSnapshotList): Update callers.

Right now, the only way to get at the contents of a virBuffer is
to destroy it.  But there are cases in my upcoming patches where
peeking at the contents makes life easier.  I suppose this does
open up the potential for bad code to dereference a stale pointer,
by disregarding the docs that the return value is invalid on the
next virBuf operation, but such is life.

* src/util/buf.h (virBufferCurrentContent): New declaration.
* src/util/buf.c (virBufferCurrentContent): Implement it.
* src/libvirt_private.syms (buf.h): Export it.
* tests/virbuftest.c (testBufAutoIndent): Test it.