While glibc provides qsort(), which usually is just a mergesort,
until sorting arrays so huge that temporary array used by
mergesort would not fit into physical memory (which in our case
is never), we are not guaranteed it'll use mergesort. The
advantage of mergesort is clear - it's stable. IOW, if we have an
array of values parsed from XML, qsort() it and produce some
output based on those values, we can then compare the output with
some expected output, line by line.
But with newer glibc this is all history. After [1], qsort() is
no longer mergesort but introsort instead, which is not stable.
This is suboptimal, because in some cases we want to preserve
order of equal items. For instance, in ebiptablesApplyNewRules(),
nwfilter rules are sorted by their priority. But if two rules
have the same priority, we want to keep them in the order they
appear in the XML. Since it's hard/needless work to identify
places where stable or unstable sorting is needed, let's just
play it safe and use stable sorting everywhere.
Fortunately, glib provides g_qsort_with_data() which indeed
implement mergesort and it's a drop in replacement for qsort(),
almost. It accepts fifth argument (pointer to opaque data), that
is passed to comparator function, which then accepts three
arguments.
We have to keep one occurance of qsort() though - in NSS module
which deliberately does not link with glib.
1: https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=03bf8357e8291857a435afcc3048e0b697b6cc04
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
If a domain has no snapshots and 'virsh snapshot-list' is called,
this gets all the way down to virshSnapshotListCollect() which
then collects all snapshots (none), and passes them to qsort()
which doesn't like being called with NULL:
extern void qsort (void *__base, size_t __nmemb, size_t __size,
__compar_fn_t __compar) __nonnull ((1, 4));
Resolves: https://gitlab.com/libvirt/libvirt/-/issues/533
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
When running virsh snapshot-* command, such as snapshot-create-as /
snapshot-delete, it prints a result message.
On the other hand virsh snapshot-revert command doesn't print a result
message.
So, This patch fixes to add message when running virsh snapshot-revert
command.
# virsh snapshot-create-as vm1 test1
Domain snapshot test01 created
# virsh snapshot-revert vm1 test1
# virsh snapshot-delete vm1 test1
Domain snapshot test01 deleted
Signed-off-by: Haruka Ohata <ohata.haruka@fujitsu.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Historically, the dumpxml command reject any unknown arguments,
for instance:
virsh dumpxml fedora xxx
However, after v8.5.0-rc1~31 the second argument ('xxx') is
treated as an XPath, but it's not that clearly visible.
Therefore, require the --xpath switch, like this:
virsh dumpxml fedora --xpath xxx
Yes, this breaks already released virsh, but I think we can argue
that the pool of users of this particular function is very small.
We also document the argument being mandatory:
dumpxml [--inactive] [--security-info] [--update-cpu] [--migratable]
[--xpath EXPRESSION] [--wrap] domain
The sooner we do this change, the better.
The same applies for other *dumpxml functions (net-dumpxml,
pool-dumpxml, vol-dumpxl to name a few).
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2103524
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
While you can chain the virsh output up to a later 'xmllint' or 'xpath'
command, integrating it into virsh avoids needs for installing extra
binaries which we've often found to be missing on production installs
of libvirt. It also gives better response if the initial virsh command
hits an error, as you don't get an aborted pipeline.
$ virsh pool-dumpxml --xpath //permissions default
<permissions>
<mode>0711</mode>
<owner>1000</owner>
<group>1000</group>
<label>unconfined_u:object_r:svirt_home_t:s0</label>
</permissions>
If multiple nodes match, they are emitted individually:
$ virsh dumpxml --xpath '//devices/*/address[@type="pci"]' --wrap demo
<address type="pci" domain="0x0000" bus="0x05" slot="0x00" function="0x0"/>
<address type="pci" domain="0x0000" bus="0x03" slot="0x00" function="0x0"/>
...snip...
<address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x0" multifunction="on"/>
<address type="pci" domain="0x0000" bus="0x07" slot="0x00" function="0x0"/>
but if intending to post-process the output further, the results
can be wrapped in a parent node
$ virsh dumpxml --xpath '//devices/*/address[@type="pci"]' --wrap demo
<nodes>
<address type="pci" domain="0x0000" bus="0x05" slot="0x00" function="0x0"/>
<address type="pci" domain="0x0000" bus="0x03" slot="0x00" function="0x0"/>
...snip...
<address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x0" multifunction="on"/>
<address type="pci" domain="0x0000" bus="0x07" slot="0x00" function="0x0"/>
</nodes>
Fixes https://gitlab.com/libvirt/libvirt/-/issues/244
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
There's no need to check whether a flag is not set just to set it
in that case.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
This wires up support for resetting NVRAM for all APIs that allow
this feature.
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This change was generated using the following spatch:
@ rule1 @
expression a;
identifier f;
@@
<...
- f(*a);
... when != a;
- *a = NULL;
+ g_clear_pointer(a, f);
...>
@ rule2 @
expression a;
identifier f;
@@
<...
- f(a);
... when != a;
- a = NULL;
+ g_clear_pointer(&a, f);
...>
Then, I left some of the changes out, like tools/nss/ (which
doesn't link with glib) and put back a comment in
qemuBlockJobProcessEventCompletedActiveCommit() which coccinelle
decided to remove (I have no idea why).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This patch includes:
* removal of dead code
* simplifying nested if conditions
* removal of unnecessary variables
* usage of "direct" boolean return
Signed-off-by: Kristina Hanicova <khanicov@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
For now this serves just as an annotation because readline and also the
bash completion script insist on completing local paths when an empty
list is returned.
This will serve for future reference once we'll be able to properly
refuse to suggest anything.
The completer is used for fields such as names for new objects,
description strings, password strings etc, URIs and hostnames which we
can't feasibly autocomplete.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
When listing a snapshot tree, the '--from' option takes a name of a
snapshot to limit the subset. Use virshSnapshotNameCompleter as
completer for the option.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
The variable is used inside a loop in which it's allocated in
each iteration. Bring it inside the loop so that g_autoptr()
kicks in each iteration.
Fixes: 3caa28dc50
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Commit 95f8e3237e which introduced XML schema validation
for snapshot XMLs always asserted the validation for the XML generated
by 'virsh snapshot-create-as' on the basis that it's libvirt-generated,
thus valid.
This unfortunately isn't true as users can influence certain bits of the
XML such as the disk image path which must be a full path. Thus if a
user tries to invoke virsh as:
$ virsh snapshot-create-as upstream --diskspec vda,file=relative.qcow2
error: XML document failed to validate against schema: Unable to validate doc against /path/to/domainsnapshot.rng
Extra element disks in interleave
Element domainsnapshot failed to validate content
They get a rather useless error from the libxml2 RNG validator.
With this fix applied, we get to the XML parser in libvirtd which has a
more reasonable error:
$ virsh snapshot-create-as upstream --diskspec vda,file=relative.qcow2
error: XML error: disk snapshot image path 'relative.qcow2' must be absolute
Instead users can force validation of the XML generated by 'virsh
snapshot-create-as' by passing the '--validate' flag.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Historically, we declared pointer type to our types:
typedef struct _virXXX virXXX;
typedef virXXX *virXXXPtr;
But usefulness of such declaration is questionable, at best.
Unfortunately, we can't drop every such declaration - we have to
carry some over, because they are part of public API (e.g.
virDomainPtr). But for internal types - we can do drop them and
use what every other C project uses 'virXXX *'.
This change was generated by a very ugly shell script that
generated sed script which was then called over each file in the
repository. For the shell script refer to the cover letter:
https://listman.redhat.com/archives/libvir-list/2021-March/msg00537.html
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Switch the allocation in virshSnapshotListCollect and
its cargo-culted Checkpoint counterpart to two separate
g_new0 calls and move the boolean expression to
the if condition that chooses between them.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Both accept a NULL value gracefully and virStringFreeList
does not zero the pointer afterwards, so a straight replace
is safe.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
After the split of virsh to multiple files, and the subsequent
split to vsh/virt-admin, there are quite a few leftovers.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
gmtime_r/localtime_r are mostly used in combination with
strftime to format timestamps in libvirt. This can all
be replaced with GDateTime resulting in simpler code
that is also more portable.
There is some boundary condition problem in parsing POSIX
timezone offsets in GLib which tickles our test suite.
The test suite is hacked to avoid the problem. The upsteam
GLib bug report is
https://gitlab.gnome.org/GNOME/glib/issues/1999
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The function now does not return an error so we can drop it fully.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Remove all the uses of vshStrdup in favor of GLib's g_strdup.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
We've been doing a terrible job of performing XML validation in our
various API that parse XML with a corresponding schema (we started
with domains back in commit dd69a14f, v1.2.12, but didn't catch all
domain-related APIs, didn't document the use of the flag, and didn't
cover other XML). New APIs (like checkpoints) should do the validation
unconditionally, but it doesn't hurt to continue retrofitting existing
APIs to at least allow the option.
While there are many APIs that could be improved, this patch focuses
on wiring up a new snapshot XML creation flag through all the
hypervisors that support snapshots, as well as exposing it in 'virsh
snapshot-create'. For 'virsh snapshot-create-as', we blindly set the
flag without a command-line option, since the XML we create from the
command line should generally always comply (note that validation
might cause failures where it used to succeed, such as if we tighten
the RNG to reject a name of '../\n'); but blindly passing the flag
means we also have to add in fallback code to disable validation if
the server is too old to understand the flag.
Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
virsh snapshot-create-as supports 'file' storage type in --diskspec by default.
But it doesn't support 'block' storage type in the virshParseSnapshotDiskspec().
So if a snapshot on a block device (e.g. LV) was created, the type of
current running storage source in dumpxml is inconsistent with the actual
backend storage source. It will check file-system type mismatch failed
and return an error message of 'Migration without shared storage is unsafe'
when VM performs a live migration after this snapshot.
Considering virsh has to be able to work remotely that recognizing a block device
by prefix /dev/ or by stat() may be not suitable, so adding a "stype" field
for the --diskspec string which will be either "file" or "block".
e.g. --diskspec vda,snapshot=external,driver=qcow2,stype=block,file=/dev/xxx.
Signed-off-by: Liu Dayu <liu.dayu@zte.com.cn>
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
When testing stuff you might want to print the XML. Interlocking it with
no metadata adds exactly 0 value to the user.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Separate the algorithm for which list members to vist (which is
generic and can be shared with checkpoints, provided that common
filtering bits are either declared with the same value or have a
mapping from public API to common value) from the decision on which
members to return (which is specific to snapshots). The typedef for
the callback function feels a bit heavy here, but will make it easier
to move the common portions in a later patch.
As part of the refactoring, note that the macros for selecting filter
bits are specific to listing functionality, so they belong better in
virdomainsnapshotobjlist.h (missed in commit 9b75154c).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
For snapshots, virsh already has a (shockingly naive [1]) client-side
topological sorter with the --tree option. But as a series of REDEFINE
calls must be presented in topological order, it's worth letting the
server do the work for us, especially since the server can give us a
topological sorting with less effort than our naive client
reconstruction.
[1] The XXX comment in virshSnapshotListCollect() about --tree being
O(n^3) is telling; https://en.wikipedia.org/wiki/Topological_sorting
is an interesting resource describing Kahn's algorithm and other
approaches for O(n) topological sorting for anyone motivated to use a
more elegant algorithm than brute force - but that doesn't affect this
patch.
For now, I am purposefully NOT implementing virsh fallback code to
provide a topological sort when the flag was rejected as unsupported;
we can worry about that down the road if users actually demonstrate
that they use new virsh but old libvirt to even need the fallback.
(The code we use for --tree could be repurposed to be such a fallback,
whether or not we keep it naive or improve it to be faster - but
again, no one should spend time on a fallback without evidence that we
need it.)
The test driver makes it easy to test:
$ virsh -c test:///default '
snapshot-create-as test a
snapshot-create-as test c
snapshot-create-as test b
snapshot-list test
snapshot-list test --topological
snapshot-list test --descendants a
snapshot-list test --descendants a --topological
snapshot-list test --tree
snapshot-list test --tree --topological
'
Without any flags, virsh does client-side sorting alphabetically, and
lists 'b' before 'c' (even though 'c' is the parent of 'b'); with the
flag, virsh skips sorting, and you can now see that the server handed
back data in a correct ordering. As shown here with a simple linear
chain, there isn't any other possible ordering, so --tree mode doesn't
seem to care whether --topological is used. But it is possible to
compose more complicated DAGs with multiple children to a parent
(representing reverting back to a snapshot then creating more
snapshots along those divergent execution timelines), where it is then
possible (but not guaranteed) that adding the --topological flag
changes the --tree output (the client-side --tree algorithm breaks
ties based on alphabetical sorting between two nodes that share the
same parent, while the --topological sort skips the client-side
alphabetical sort and ends up exposing the server's internal order for
siblings, whether that be historical creation order or dependent on a
random hash seed). But even if the results differ, they will still be
topologically correct.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
In these cases the check that is removed has been done a few
lines above already (as can even be seen in the context). Drop
them.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Upcoming patches plan to introduce virDomainCheckpointPtr as a new
object for use in incremental backups, along with documentation on
how incremental backups differ from snapshots. But first, we need
to rename any existing mention of a 'system checkpoint' to instead
be a 'full system snapshot', so that we aren't overloading
the term checkpoint.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
The root snapshot does not have a parent.
Use NULLSTR_EMPTY to pass an empty string instead of putting
too few columns in the table.
https://bugzilla.redhat.com/show_bug.cgi?id=1662849
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Use the newly introduced macro in the few places that open-code it.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
We have this very handy macro called VIR_STEAL_PTR() which steals
one pointer into the other and sets the other to NULL. The
following coccinelle patch was used to create this commit:
@ rule1 @
identifier a, b;
@@
- b = a;
...
- a = NULL;
+ VIR_STEAL_PTR(b, a);
Some places were clean up afterwards to make syntax-check happy
(e.g. some curly braces were removed where the body become a one
liner).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
In 600462834f we've tried to remove Author(s): lines
from comments at the beginning of our source files. Well, in some
files while we removed the "Author" line we did not remove the
actual list of authors.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
The helper function virshSnapshotCreate (formerly vshSnapshotCreate)
has had dead variables since commit a00c37f2 (Sep 2011).
Signed-off-by: Eric Blake <eblake@redhat.com>
centralize the definition of macro VIRSH_COMMON_OPT_DOMAIN_FULL to virsh.h
to avoid unnecessary duplicated definition
Signed-off-by: Lin Ma <lma@suse.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Now that we have everything prepared let the fun begin. This
completer is very simple and returns domain names. Moreover,
depending on the command it can return just a subset of domains
(e.g. only running/paused/transient/.. ones).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
In some cases there's dangling backward slash at the end of multi
line macros. While technically the code works, it will stop if
some empty lines are removed.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Right-aligning backslashes when defining macros or using complex
commands in Makefiles looks cute, but as soon as any changes is
required to the code you end up with either distractingly broken
alignment or unnecessarily big diffs where most of the changes
are just pushing all backslashes a few characters to one side.
Generated using
$ git grep -El '[[:blank:]][[:blank:]]\\$' | \
grep -E '*\.([chx]|am|mk)$$' | \
while read f; do \
sed -Ei 's/[[:blank:]]*[[:blank:]]\\$/ \\/g' "$f"; \
done
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
