Audit all changes to the qemu vm->current_snapshot, and make them
update the saved xml file for both the previous and the new
snapshot, so that there is always at most one snapshot with
<active>1</active> in the xml, and that snapshot is used as the
current snapshot even across libvirtd restarts.

This patch does not fix the case of virDomainSnapshotDelete(,CHILDREN)
where one of the children is the current snapshot; that will be later.

* src/conf/domain_conf.h (_virDomainSnapshotDef): Alter member
type and name.
* src/conf/domain_conf.c (virDomainSnapshotDefParseString)
(virDomainSnapshotDefFormat): Update clients.
* docs/schemas/domainsnapshot.rng: Tighten rng.
* src/qemu/qemu_driver.c (qemuDomainSnapshotLoad): Reload current
snapshot.
(qemuDomainSnapshotCreateXML, qemuDomainRevertToSnapshot)
(qemuDomainSnapshotDiscard): Track current snapshot.

Changing the current vm, and writing that change to the file
system, all before a new qemu starts, is risky; it's hard to
roll back if starting the new qemu fails for some reason.
Instead of abusing vm->current_snapshot and making the command
line generator decide whether the current snapshot warrants
using -loadvm, it is better to just directly pass a snapshot all
the way through the call chain if it is to be loaded.

This frees up the last use of snapshot->def->active for qemu's
use, so the next patch can repurpose that field for tracking
which snapshot is current.

* src/qemu/qemu_command.c (qemuBuildCommandLine): Don't use active
field of snapshot.
* src/qemu/qemu_process.c (qemuProcessStart): Add a parameter.
* src/qemu/qemu_process.h (qemuProcessStart): Update prototype.
* src/qemu/qemu_migration.c (qemuMigrationPrepareAny): Update
callers.
* src/qemu/qemu_driver.c (qemudDomainCreate)
(qemuDomainSaveImageStartVM, qemuDomainObjStart)
(qemuDomainRevertToSnapshot): Likewise.
(qemuDomainSnapshotSetCurrentActive)
(qemuDomainSnapshotSetCurrentInactive): Delete unused functions.

https://bugzilla.redhat.com/show_bug.cgi?id=727709
mentions that if qemu fails to create the snapshot (such as what
happens on Fedora 15 qemu, which has qmp but where savevm is only
in hmp, and where libvirt is old enough to not try the hmp fallback),
then 'virsh snapshot-list dom' will show a garbage snapshot entry,
and the libvirt internal directory for storing snapshot metadata
will have a bogus file.

This fixes the fallout bug of polluting the snapshot-list with
garbage on failure (the root cause of the F15 bug of not having
fallback to hmp has already been fixed in newer libvirt releases).

* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML): Allocate
memory before making snapshot, and cleanup on failure.  Don't
dereference NULL if transient domain exited during snapshot creation.

* 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
    ^     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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

Detected by ccc-analyzer:

  CC     libvirt_driver_qemu_la-qemu_migration.lo
qemu/qemu_migration.c:2046:5: warning: Value stored to 'ret' is never read
    ret = qemuMigrationConfirm(driver, sconn, vm,
    ^     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The VIR_TEST_DEBUG and VIR_TEST_VERBOSE env vars did not work
because we replaced 'environ' with 'newenv'. Simply calling
virTestGetDebug/Verbose() before replacing the 'environ' ensures
we have processed the env variables.

The gnutls initialization code opens /dev/urandom and keeps that
FD around for later use. We have code which kills off FDs 3-5
to avoid interfereing with our test case. Move the virInitialize
call before this point, so it kills off the gnutls /dev/urandom
FD which is irrelevant for testing purposes

* tests/commandtest.c: Fix test debugging & make it robust against
  opened FDs

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

virFileOpenAs takes desired uid:gid as arguments, and not only uses
them for a fork/setuid/setgid when retrying failed open operations,
but additionally always forces the opened file to be owned by the
given uid:gid.

One example of the problems this causes is that, when restoring a
domain from a file that is owned by the qemu user, opening the file
chowns it to root. if dynamic_ownership=1 this is coincidentally
expected, but if dynamic_ownership=0, no existing file should ever
have its ownership changed.

This patch adds an extra check before calling fchown() - it only does
it if O_CREAT was passed to virFileOpenAs() in the openflags.

Signed-off-by: NSteve Hodgson <shodgson@solarflare.com>

Signed-off-by: NEric Blake <eblake@redhat.com>

pciDeviceListSteal(pcidevs, dev) removes dev from pcidevs reducing
the length of pcidevs, so moving onto what was the next dev is wrong.

Instead callers should pop entry 0 repeatedly until pcidevs is empty.
Signed-off-by: NSteve Hodgson <shodgson@solarflare.com>
Signed-off-by: NShradha Shah <sshah@solarflare.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

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.

Knowing whether 'virsh start' will resume a saved image or do
a fresh boot is useful enough to expose via 'virsh list'.

Also, translate the state column.

* tools/virsh.c (cmdList): add --managed-save flag
* tools/virsh.pod (list): Document it.
Based on a suggestion by Miklos Vajna.

* src/qemu/qemu_monitor_json.c: Handle error "CommandNotFound" and
  report the error.

* src/qemu/qemu_monitor_text.c: If a sub info command is not found,
  it prints the output of "help info", for other commands,
  "unknown command" is printed.

Without this patch, libvirt always report:

  An error occurred, but the cause is unknown

This patch was adapted from a patch by Osier Yang <jyang@redhat.com> to
break out detection of unrecognized text monitor commands into a separate
function.
Signed-off-by: NAdam Litke <agl@us.ibm.com>

* src/qemu/qemu_driver.c (qemuDomainSaveInternal): Fix typo.
* src/conf/domain_event.c (virDomainEventDispatchMatchCallback):
Likewise.
* daemon/libvirtd.c (daemonRunStateInit): Likewise.
* src/lxc/lxc_container.c (lxcContainerChildMountSort): Likewise.
* src/util/virterror.c (virCopyError, virRaiseErrorFull): Likewise.
* src/xenxs/xen_sxpr.c (xenParseSxprSound): Likewise.

Introduced by 241cbc13, pushed under urgent rule.

Without these patch, there will be error like below if domain
is NULL.

error: invalid domain pointer in virDomainFree

Which is useless.

* src/qemu/qemu_command.c: s/VIR_ERR_NO_SUPPORT/VIR_ERR_CONFIG_UNSUPPORTED/

* src/qemu/qemu_driver.c: s/VIR_ERR_NO_SUPPORT/VIR_ERR_OPERATION_INVALID/

* src/qemu/qemu_process.c: s/VIR_ERR_NO_SUPPORT/VIR_ERR_OPERATION_INVALID/

s/VIR_ERR_NO_SUPPORT/VIR_ERR_OPERATION_INVALID/

Special case is changes on lxcDomainInterfaceStats, if it's not
implemented on the platform, prints error like:

    lxcError(VIR_ERR_OPERATION_INVALID, "%s",
             _("interface stats not implemented on this platform"));

As the function is supported by driver actually, error like
VIR_ERR_NO_SUPPORT is confused.

* src/qemu/qemu_monitor_text.c: Error like "this function is not
supported by the connection driver" is confused obviously.

It's strange that the command fails but without any error if one
specifies as not a number.

Now, bad key-code in send-key can cause segmentation fault in libvirt.
(example)
 % virsh send-key --codeset win32 12
   error: End of file while reading data: Input/output error

This is caused by overrun at scanning keycode array.

Fix it.
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>

Systemtap 1.2 <sys/sdt.h> tried to expand STAP_PROBE3 into an
initialization:
  volatile __typeof__(arg) foo = arg;
but that fails if arg was declared as 'char arg[100]'.
Rather than make all callers to PROBE deal with the stupidity
of <sys/sdt.h>, we instead make PROBE cast away the problem.
Some of this preprocessor abuse copies ideas in src/libvirt.c.

* daemon/libvirtd.h (PROBE): Add casts to all arguments, using...
(VIR_ADD_CASTS, VIR_ADD_CAST, VIR_ADD_CAST2, VIR_ADD_CAST3)
(VIR_ADD_CAST_EXPAND, VIR_ADD_CAST_PASTE, VIR_COUNT_ARGS)
(VIR_ARG5, PROBE_EXPAND): New macros.
Reported by Wen Congyang.

Without this patch, invoking 'virsh >file 2>&1' results in
error messages appearing before normal output, even if they
occurred later in time than the normal output (since stderr
is unbuffered, but stdout waits until a full buffer).

* tools/virsh.c (print_job_progress, vshError): Flush between
stream transitions.
* tests/undefine: Test it.

Repetitive patterns should be factored.  The sign of a good
factorization is a change that kills 5x more lines than it adds :)

* src/conf/domain_conf.c (virDomainDeviceDefParse)
(virDomainSnapshotDefParseString): Use new convenience macros.
* src/conf/storage_conf.c (virStoragePoolDefParseSourceString):
Likewise.
* src/cpu/cpu.c (cpuCompareXML, cpuBaselineXML): Likewise.
* src/esx/esx_vi.c (esxVI_Context_Execute): Likewise.
* src/qemu/qemu_migration.c (qemuMigrationCookieXMLParseStr):
Likewise.
* src/security/virt-aa-helper.c (caps_mockup): Likewise.
* src/test/test_driver.c (testOpenFromFile): Likewise.
* tests/cputest.c (cpuTestLoadXML, cpuTestLoadMultiXML):
Likewise.
* tools/virsh.c (cmdFreecell, makeCloneXML, cmdVNCDisplay)
(cmdTTYConsole, cmdDetachInterface, cmdDetachDisk)
(cmdSnapshotCreate, cmdSnapshotCreateAs, cmdSnapshotCurrent)
(cmdSnapshotList, cmdSnapshotParent): Likewise.

Often, we want to use XPath functions on the just-parsed document;
fold this into the parser function for convenience.

* src/util/xml.h (virXMLParseHelper): Add argument.
(virXMLParseStrHelper, virXMLParseFileHelper): Delete.
(virXMLParseCtxt, virXMLParseStringCtxt, virXMLParseFileCtxt): New
macros.
* src/libvirt_private.syms (xml.h): Remove deleted functions.
* src/util/xml.c (virXMLParseHelper): Add argument.
(virXMLParseStrHelper, virXMLParseFileHelper): Delete.

* cfg.mk (useless_free_options): Add xmlFreeDoc, xmlBufferFree.
* src/esx/esx_vi.c (ESX_VI__TEMPLATE__FREE): Fix offenders.
* tools/virsh.c (cmdFreecell, cmdVNCDisplay, cmdTTYConsole)
(cmdDetachInterface, cmdDetachDisk, cmdSnapshotCreate)
(cmdSnapshotCreateAs, cmdSnapshotList, cmdSnapshotParent):
Likewise.

Test failure exposed in commit 7d3390f8.

* tests/undefine: Fix to match updated test driver semantics.

* src/test/test_driver.c (testDomainUndefineFlags): Use right
variable name.

ACK was given too soon.  According to the code, the xm driver is
only used for inactive domains, and has no notion of an active
domain, thus, it cannot support undefine of a running domain.
The real fix for xen needs to be in the unified driver and/or
the xend level.

This reverts commit 49186ded.