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>
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>
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>
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>
Via coccinelle (not the handbag!)
spatches used:
@ rule1 @
identifier a, b;
symbol NULL;
@@
- b = a;
... when != a
- a = NULL;
+ b = g_steal_pointer(&a);
@@
- *b = a;
... when != a
- a = NULL;
+ *b = g_steal_pointer(&a);
Signed-off-by: Kristina Hanicova <khanicov@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
The enum constant names should all have a prefix that matches the enum
name. VIR_DOMAIN_CHECKPOINT_REDEFINE_VALIDATE was missing the "CREATE_"
part of the name prefix.
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@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>
Compilers are not very good at detecting this problem. Fixed by manual
inspection of compilation warnings after replacing 'VIR_FREE' with an
empty macro.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@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>
Introduce a bunch of new virsh commands for managing checkpoints in
isolation. More commands are needed for performing incremental
backups, but these commands were easy to implement by modeling heavily
after virsh-snapshot.c. There is no need for checkpoint-revert or
checkpoint-current since those snapshot APIs have no checkpoint
counterpart. Similarly, it is not necessary to change which
checkpoint is current when redefining from XML, since until we
integrate checkpoints with snapshots, there is only a linear chain
(and you can deduce the current checkpoint by instead using
'checkpoint-list --leaves'). Other aspects of checkpoint-list are
also a bit simpler than the snapshot counterpart, in part because we
don't have to cater to back-compat to older API.
Upcoming patches will test these interfaces once the test driver
supports checkpoints.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
