Currently, push & pop from event queue (both server & client side)
rely on lock from higher levels, e.g. on driver lock (qemu),
private_data (remote), ...; This alone is not sufficient as not
every function that interacts with this queue can/does lock,
esp. in client where we have a different approach, "passing
the buck".

Therefore we need a separate lock just to protect event queue.

For more info see:
https://bugzilla.redhat.com/show_bug.cgi?id=743817

This patch extends qemudDomainCoreDump so it supports new VIR_DUMP_RESET
flag. If this flag is set, domain is reset on successful dump. However,
this is needed to be done after we start CPUs.

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

With the recent refactoring of qemu snapshot relationships, it
is now trivial to filter on leaves.

* src/conf/domain_conf.c (virDomainSnapshotObjListCount)
(virDomainSnapshotObjListCopyNames): Handle new flag.
* src/qemu/qemu_driver.c (qemuDomainSnapshotListNames)
(qemuDomainSnapshotNum, qemuDomainSnapshotListChildrenNames)
(qemuDomainSnapshotNumChildren): Pass new flag through.

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.

For some versions of Xen the difference between "tap" and "tap2" is
important. When converting back from xen-sxpr to libvirt-xml, that
information is lost, which breaks re-defining the domain using that
data.

Explicitly return "tap2" for disks defined as "device/tap2".
Signed-off-by: NPhilipp Hahn <hahn@univention.de>

When PyGrub is used as the bootloader in Xen, it gets passed the first
bootable disk. Xend supports a "bootable"-flag for this, which isn't
explicitly supported by libvirt.
When converting libvirt-xml to xen-sxpr the "bootable"-flag gets
implicitly set by xen.xend.XenConfig.device_add() for the first disk
(marked as "Compat hack -- mark first disk bootable").
When converting back xen-sxpr to libvirt-xml, the disks are returned in
the internal order used by Xend ignoring the "bootable"-flag, which
loses the original order. When the domain is then re-defined, the order
of disks is changed, which breaks PyGrub, since a different disk gets
passed.

When converting xen-sxpr to libvirt-xml, use the "bootable"-flag to
determine the first disk.

This isn't perfect, since several disks can be marked as bootable using
the Xend-API, but that is not supported by libvirt. In all known cases
relevant to libvirt exactly one disk is marked as bootable.
Signed-off-by: NPhilipp Hahn <hahn@univention.de>

VirtFS allows the user to choose between path/handle based fs driver.
As of now, libvirt hardcoded path based driver only. This patch provides
a solution to allow user to choose between path/handle based fs driver.

Sample:

    <filesystem type='mount'>
      <driver type='handle'/>
      <source dir='/folder/to/share1'/>
      <target dir='mount_tag1'/>
    </filesystem>

    <filesystem type='mount'>
      <driver type='path'/>
      <source dir='/folder/to/share2'/>
      <target dir='mount_tag2'/>
    </filesystem>
Signed-off-by: NHarsh Prateek Bora <harsh@linux.vnet.ibm.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

Implement a generic helper to escape a given set of characters with a
leading '\'.  Generalizes virBufferEscapeSexpr().
Signed-off-by: NSage Weil <sage@newdream.net>

The previous optimizations lead to some follow-on cleanups.

* src/conf/domain_conf.c (virDomainSnapshotForEachChild)
(virDomainSnapshotForEachDescendant): Drop dead parameter.
(virDomainSnapshotActOnDescendant)
(virDomainSnapshotObjListNumFrom)
(virDomainSnapshotObjListGetNamesFrom): Update callers.
* src/qemu/qemu_driver.c (qemuDomainSnapshotNumChildren)
(qemuDomainSnapshotListChildrenNames, qemuDomainSnapshotDelete):
Likewise.
* src/conf/domain_conf.h: Update prototypes.

Among other improvements, virDomainSnapshotForEachDescendant is
changed from iterative O(n^2) to recursive O(n).  A bit better
than the O(n^3) implementation in virsh snapshot-list!

* src/conf/domain_conf.c (virDomainSnapshotObjListNum)
(virDomainSnapshotObjListNumFrom)
(virDomainSnapshotObjeListGetNames, virDomainSnapshotForEachChild)
(virDomainSnapshotForEachDescendant): Optimize.
(virDomainSnapshotActOnDescendant): Tweak.
(virDomainSnapshotActOnChild, virDomainSnapshotMarkDescendant):
Delete, now that they are unused.

Maintain the parent/child relationships of all qemu snapshots.

* src/qemu/qemu_driver.c (qemuDomainSnapshotLoad): Populate
relationships after loading.
(qemuDomainSnapshotCreateXML): Set relations on creation; tweak
redefinition to reuse existing object.
(qemuDomainSnapshotReparentChildren, qemuDomainSnapshotDelete):
Clear relations on delete.

No one was using virDomainSnapshotHasChildren, but that was an
O(n) function.  Exposing and tracking a bit more metadata for each
snapshot will allow the same query to be made with an O(1) query
of the member field.  For single snapshot operations (create,
delete), callers can be trusted to maintain the metadata themselves,
but for reloading, we can't compute parents as we go since there
is no guarantee that parents were parsed before children, so we also
provide a function to refresh the relationships, and which can
be used to detect if the user has ignored our warnings and been
directly modifying files in /var/lib/libvirt/qemu/snapshot.  This
patch only adds metadata; later patches will actually use it.

This layout intentionally hardcodes the size of each snapshot struct,
by tracking sibling pointers, rather than having to deal with the
headache of yet more memory management by directly sticking a
dynamically sized child[] on each parent.

* src/conf/domain_conf.h (_virDomainSnapshotObj)
(_virDomainSnapshotObjList): Add members.
(virDomainSnapshotUpdateRelations, virDomainSnapshotDropParent):
New prototypes.
(virDomainSnapshotHasChildren): Delete.
* src/conf/domain_conf.c (virDomainSnapshotSetRelations)
(virDomainSnapshotUpdateRelations, virDomainSnapshotDropParent):
New functions.
(virDomainSnapshotHasChildren): Drop unused function.
* src/libvirt_private.syms (domain_conf): Update exports.

To date, JSON disk snapshots worked by accident, as they were always
using hmp fallback due to a typo in commit e702b5ba not picking up
on the (intentional) difference in command names between the two
monitor protocols.

* src/qemu/qemu_monitor_json.c (qemuMonitorJSONDiskSnapshot):
Spell QMP command correctly.
Reported by Luiz Capitulino.

Detected by autogen.sh on a cross-mingw build:

Creating library file: .libs/libvirt.dll.a
Cannot export virNetSASLContextCheckIdentity: symbol not defined
Cannot export virNetSASLContextNewServer: symbol not defined
...

* src/libvirt_private.syms (virnetsaslcontext.h): Move symbols...
* src/libvirt_sasl.syms: ...to new file.
* src/Makefile.am (USED_SYM_FILES) [HAVE_SASL]: Use new file.
(EXTRA_DIST): Ship it.

I got these distcheck failures with sanlock enabled:

ERROR: files left in build directory after distclean:
./tools/virt-sanlock-cleanup
./src/locking/qemu-sanlock.conf

* src/Makefile.am (DISTCLEANFILES) [HAVE_SANLOCK]: Clean built
file.
* tools/Makefile.am (DISTCLEANFILES): Likewise.

Otherwise, 'make rpm' fails with:

  GEN    libvirt_qemu.def
make[2]: *** No rule to make target `dtrace2systemtap.pl', needed by `libvirt_probes.stp'.  Stop.

* src/Makefile.am (EXTRA_DIST): Add recent script additions.

The libvirtd daemon had a few crude system tap probes. Some of
these were broken during the RPC rewrite. The new modular RPC
code is structured in a way that allows much more effective
tracing. Instead of trying to hook up the original probes,
define a new set of probes for the RPC and event code.

The master probes file is now src/probes.d.  This contains
probes for virNetServerClientPtr, virNetClientPtr, virSocketPtr
virNetTLSContextPtr and virNetTLSSessionPtr modules. Also add
probes for the poll event loop.

The src/dtrace2systemtap.pl script can convert the probes.d
file into a libvirt_probes.stp file to make use from systemtap
much simpler.

The src/rpc/gensystemtap.pl script can generate a set of
systemtap functions for translating RPC enum values into
printable strings. This works for all RPC header enums (program,
type, status, procedure) and also the authentication enum

The PROBE macro will automatically generate a VIR_DEBUG
statement, so any place with a PROBE can remove any existing
manual DEBUG statements.

* daemon/libvirtd.stp, daemon/probes.d: Remove obsolete probing
* daemon/libvirtd.h: Remove probe macros
* daemon/Makefile.am: Remove all probe buildings/install
* daemon/remote.c: Update authentication probes
* src/dtrace2systemtap.pl, src/rpc/gensystemtap.pl: Scripts
  to generate STP files
* src/internal.h: Add probe macros
* src/probes.d: Master list of probes
* src/rpc/virnetclient.c, src/rpc/virnetserverclient.c,
  src/rpc/virnetsocket.c, src/rpc/virnettlscontext.c,
  src/util/event_poll.c: Insert probe points, removing any
  DEBUG statements that duplicate the info

The virNetTLSContextRef API forgot to acquire/release the lock
while changing ctxt->refs

* src/rpc/virnettlscontext.c: Add lock calls

Pull the call to gnutls_x509_crt_get_dn up into a higher function
so that the 'dname' variable will be available for probe points

* src/rpc/virnettlscontext.c: Pull gnutls_x509_crt_get_dn up
  one level

Instead of directly manipulating sock->refs, add a virSocketRef
API

* src/rpc/virnetsocket.c, src/rpc/virnetsocket.h: Add virSocketRef

If we receive an error on the stream, set the EOF marker so
that any further (bogus) incoming data is dropped.

* src/rpc/virnetclientstream.c: Set EOF on stream

To avoid static linking libvirtd to the RPC server code, which
then prevents sane introduction of DTrace probes, put it all
in the libvirt.so, and export it

* daemon/Makefile.am: Don't link to RPC libraries
* src/Makefile.am: Link all RPC libraries to libvirt.so
* src/libvirt_private.syms: Export all RPC functions

It was fairly trivial to return snapshot listing based on a
point in the hierarchy, rather than starting at all roots.

* src/esx/esx_driver.c (esxDomainSnapshotNumChildren)
(esxDomainSnapshotListChildrenNames): New functions.

Not too hard to wire up.  The trickiest part is realizing that
listing children of a snapshot cannot use SNAPSHOT_LIST_ROOTS,
and that we overloaded that bit to also mean SNAPSHOT_LIST_DESCENDANTS;
we use that bit to decide which iteration to use, but don't want
the existing counting/listing functions to see that bit.

* src/conf/domain_conf.h (virDomainSnapshotObjListNumFrom)
(virDomainSnapshotObjListGetNamesFrom): New prototypes.
* src/conf/domain_conf.c (virDomainSnapshotObjListNumFrom)
(virDomainSnapshotObjListGetNamesFrom): New functions.
* src/libvirt_private.syms (domain_conf.h): Export them.
* src/qemu/qemu_driver.c (qemuDomainSnapshotNumChildren)
(qemuDomainSnapshotListChildrenNames): New functions.

Very mechanical.  I'm so glad we've automated the generation of things,
compared to what it was in 0.8.x days, where this would be much longer.

* src/remote/remote_protocol.x
(REMOTE_PROC_DOMAIN_SNAPSHOT_NUM_CHILDREN)
(REMOTE_PROC_DOMAIN_SNAPSHOT_LIST_CHILDREN_NAMES): New rpcs.
(remote_domain_snapshot_num_children_args)
(remote_domain_snapshot_num_children_ret)
(remote_domain_snapshot_list_children_names_args)
(remote_domain_snapshot_list_children_names_ret): New structs.
* src/remote/remote_driver.c (remote_driver): Use it.
* src/remote_protocol-structs: Update.

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.

On xen 4.1 I observed configurations that look like:

(image
    (hvm
        (kernel '')
        (loader '/foo/bar')
))

The kernel element is there but unset. This leads to an empty <kernel/>
element in the XML and even worse makes us skip the boot order parsing
and therefore not emit a <boot device='$dev>'/> element which breaks CD
booting.

otherwise a missing UUID in a domain config just shows:

error: An error occurred, but the cause is unknown

Now we have:

error: configuration file syntax error: config value uuid was missing

I noticed a couple typos in recent commits, and fixed the remaining
instances of them.

* docs/internals/command.html.in: Fix spelling errors.
* include/libvirt/libvirt.h.in (virConnectDomainEventCallback):
Likewise.
* python/libvirt-override.py (virEventAddHandle): Likewise.
* src/lxc/lxc_container.c (lxcContainerChild): Likewise.
* src/util/hash.c (virHashCreateFull): Likewise.
* src/storage/storage_backend_logical.c
(virStorageBackendLogicalMakeVol): Likewise.
* src/esx/esx_driver.c (esxFormatVMXFileName): Likewise.
* src/vbox/vbox_tmpl.c (vboxIIDIsEqual_v3_x): Likewise.

* src/storage/storage_backend_logical.c:

If a logical vol is created as striped. (e.g. --stripes 3),
the "device" field of lvs output will have multiple fileds which are
seperated by comma. Thus the RE we write in the codes will not
work well anymore. E.g. (lvs output for a stripped vol, uses "#" as
seperator here):

test_stripes##fSLSZH-zAS2-yAIb-n4mV-Al9u-HA3V-oo9K1B#\
/dev/sdc1(10240),/dev/sdd1(0)#42949672960#4194304

The RE we use:

    const char *regexes[] = {
        "^\\s*(\\S+),(\\S*),(\\S+),(\\S+)\\((\\S+)\\),(\\S+),([0-9]+),?\\s*$"
    };

Also the RE doesn't match the "devices" field of striped vol properly,
it contains multiple "device path" and "offset".

This patch mainly does:
    1) Change the seperator into "#"
    2) Change the RE for "devices" field from "(\\S+)\\((\\S+)\\)"
       into "(\\S+)".
    3) Add two new options for lvs command, (segtype, stripes)
    4) Extend the RE to match the value for the two new fields.
    5) Parse the "devices" field seperately in virStorageBackendLogicalMakeVol,
       multiple "extents" info are generated if the vol is striped. The
       number of "extents" is equal to the stripes number of the striped vol.

A incidental fix: (virStorageBackendLogicalMakeVol)
    Free "vol" if it's new created and there is error.

Demo on striped vol with the patch applied:

% virsh vol-dumpxml /dev/test_vg/vol_striped2
<volume>
  <name>vol_striped2</name>
  <key>QuWqmn-kIkZ-IATt-67rc-OWEP-1PHX-Cl2ICs</key>
  <source>
    <device path='/dev/sda5'>
      <extent start='79691776' end='88080384'/>
    </device>
    <device path='/dev/sda6'>
      <extent start='62914560' end='71303168'/>
    </device>
  </source>
  <capacity>8388608</capacity>
  <allocation>8388608</allocation>
  <target>
    <path>/dev/test_vg/vol_striped2</path>
    <permissions>
      <mode>0660</mode>
      <owner>0</owner>
      <group>6</group>
      <label>system_u:object_r:fixed_disk_device_t:s0</label>
    </permissions>
  </target>
</volume>

RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=727474

If parsing qemu command line fails (e.g. because of non-existing
process number supplied), we jump to cleanup label where we free
pidfile. Therefore it needs to be initialized. Otherwise we free
random pointer.

Coverity complained that 4 out of 5 callers to virJSONValueObjectGetBoolean
checked for errors.  But we documented that we don't care in this case.

* src/qemu/qemu_monitor_json.c (qemuMonitorJSONGetBlockInfo): Use
ignore_value.

Detected by Coverity.  We want to increment the size_t counter,
not the pointer to the counter.  Bug present since 5f5c6fde (0.9.5).

* src/lxc/lxc_controller.c (lxcSetupLoopDevices): Use correct
precedence.

If we send back an unknown program error for async messages,
we will confuse the client because they only expect replies
for method calls. Just log & drop any invalid async messages

* src/rpc/virnetserver.c: Don't send error for async messages

Commit 597fe3ce accidentally
introduced a deadlock when reporting an unknown RPC program.
The virNetServerDispatchNewMessage method is called with
the client locked, and must therefore not attempt to send
any RPC messages back to the client. Only once the incoming
message is passed off to the virNetServerHandleJob worker
is it safe to start sending messages back

* src/rpc/virnetserver.c: Delay checking for unknown RPC
  program until in worker thread

Redefining disk-only snapshot xml should work even if the user
did not explicitly pass VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY;
the flag is only required for conditions where the <state>
subelement is not already present in parsing (that is, defining
a new snapshot).

Also, fix the error code of some user-visible errors (the remaining
VIR_ERR_INTERNAL_ERROR should not be user-visible, since parsing
of <active> is only done from internal code).

* src/conf/domain_conf.c (virDomainSnapshotDefParseString): Allow
disks during redefinition of disk snapshot.

Don't xdr_free event data as they are freed by our caller
virNetClientProgramDispatch.

I am getting this failure with 'make distcheck':

  GEN    ../../src/remote_protocol-structs
/bin/sh: ../../src/remote_protocol-structs-t: Permission denied
make[4]: *** [../../src/remote_protocol-structs] Error 1

since it attempts a sub-run of a VPATH 'make check' where $(srcdir)
is intentionally read-only.  I'm not sure which commit introduced
the problem, although I suspect it was around 62dee6fa when I
refactored protocol struct checking to be more powerful.

$(@F) is required by POSIX, and although it is not yet portable
to all make implementations, we already require GNU make.

* src/Makefile.am (PDWTAGS): Generate temp file into current
directory, since $(srcdir) is read-only during distcheck.