Commit Graph

150 Commits

Author SHA1 Message Date
Ján Tomko
c727638b4b include: add a space before ending a comment
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
2020-01-28 13:32:28 +01:00
Julio Faracco
3cf12299f6 Introduce source flags to virDomainGetHostname()
There is a lots of possibilities to retrieve hostname information
from domain. Libvirt could use lease information from dnsmasq to
get current hostname too. QEMU supports QEMU-agent but it can use
lease source.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2020-01-16 09:02:35 +01:00
Cole Robinson
f854e051b9 Remove phyp driver
The phyp driver was added in 2009 and does not appear to have had any
real feature change since 2011. There's virtually no evidence online
of users actually using it. IMO it's time to kill it.

This was discussed a bit in April 2016:
https://www.redhat.com/archives/libvir-list/2016-April/msg01060.html

Final discussion is here:
https://www.redhat.com/archives/libvir-list/2019-December/msg01162.html

Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
2019-12-20 12:25:42 -05:00
Pavel Hrdina
07946d6e39 util: introduce virbpf helpers
In order to implement devices controller with cgroup v2 we need to
add support for BPF programs, cgroup v2 doesn't have devices controller.

This introduces required helpers wrapping linux syscalls.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-11-15 12:58:00 +01:00
Stefan Berger
1f46dd4cba tpm: Parse the capabilities supported by swtpm and swtpm_setup
Run 'swtpm socket --print-capabilities' and
'swtpm_setup --print-capabilities' to get the JSON object of the
features the programs are supporting and parse them into a bitmap.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-07-26 10:30:46 +01:00
Daniel P. Berrangé
bd17012f0c Revert "error: Add VIR_ERR_DEPRECATED error code"
This reverts commit 226094fbc4.

A deprecation is a warning to something that use of a feature is
being discouraged. By definition it is not an error condition to
continue to use a deprecated feature.

A VIR_ERR_DEPRECATED constant thus makes no conceptual sense. For
features which are entirely absent we already document that the
VIR_ERR_NO_SUPPORT code will be used. There is no need to distinguish
between a feature which never existed and a feature which previously
existed and was since removed.

Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-06-27 14:47:10 +01:00
Peter Krempa
226094fbc4 error: Add VIR_ERR_DEPRECATED error code
Allow a simple programatic check that a given feature is no longer
supported by introducing a separate error code for this scenario.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-06-26 08:37:01 +02:00
Daniel P. Berrangé
c08fc8d199 network: add public APIs for network port object
Introduce a new virNetworPort object that will present an attachment to
a virtual network from a VM.

Reviewed-by: Laine Stump <laine@laine.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-06-17 15:19:54 +01:00
Eric Blake
421861824c backup: Introduce virDomainCheckpointPtr
Prepare for introducing a bunch of new public APIs related to
backup checkpoints by first introducing a new internal type
and errors associated with that type.  Checkpoints are modeled
heavily after virDomainSnapshotPtr (both represent a point in
time of the guest), although a snapshot exists with the intent
of rolling back to that state, while a checkpoint exists to
make it possible to create an incremental backup at a later
time.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-03-26 15:40:57 -05:00
Laine Stump
d8393b56e2 util: move all firewalld-specific stuff into its own files
In preparation for adding several other firewalld-specific functions,
separate the code that's unique to firewalld from the more-generic
"firewall" file.

Signed-off-by: Laine Stump <laine@laine.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-02-01 12:08:37 -05:00
Michal Privoznik
29682196d8 Drop UML driver
The driver is unmaintained, untested and severely broken for
quite some time now. Since nobody even reported any issue with it
let us drop it.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-17 17:52:46 +01:00
Peter Krempa
590cc60de5 include: error: Add enum sentinel for virErrorNumber enum
We do have one for the error domain but not for the error number itself.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2018-12-14 13:28:43 +01:00
Daniel P. Berrangé
568a417224 Enforce a standard header file guard symbol name
Require that all headers are guarded by a symbol named

  LIBVIRT_$FILENAME

where $FILENAME is the uppercased filename, with all characters
outside a-z changed into '_'.

Note we do not use a leading __ because that is technically a
namespace reserved for the toolchain.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-14 10:47:13 +00:00
Daniel P. Berrangé
600462834f Remove all Author(s): lines from source file headers
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.

In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.

With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to  find the
author of a particular bit of code.

This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.

The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.

Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-13 16:08:38 +00:00
Daniel P. Berrangé
b57a9aecaf nwfilter: export port binding concept in the public API
When the daemons are split there will need to be a way for the virt
drivers and/or network driver to create and delete bindings between
network ports and network filters. This defines a set of public APIs
that are suitable for managing this facility.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-06-26 11:22:07 +01:00
ramyelkest
50e96bb2a1 util: virerror: Introduce virGetLastError{Code,Domain} public APIs
Many places in the code call virGetLastError() just to check the
raised error code, or domain. However virGetLastError() can return
NULL, so the code has to check for that first. This patch therefore
introduces virGetLasError{Code,Domain} functions which always return a
valid error code or domain respectively, thus dropping the need to
perform any checks on the error object.

Signed-off-by: Ramy Elkest <ramyelkest@gmail.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2018-06-05 18:44:05 +02:00
Chen Hanxiao
bb189c8e8c qemu: Introduce VIR_ERR_DEVICE_MISSING
Add new error code to be able to allow consumers (such as Nova) to be
able to key of a specific error code rather than needing to search the
error message."

Signed-off-by: Chen Hanxiao <chenhanxiao@gmail.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-02-01 07:17:01 -05:00
Chen Hanxiao
c416a20db1 virerror: mark VIR_ERR_AGENT_UNSYNCED as DEPRECATED
Since commit 5e5019bf, we've no longer use
VIR_ERR_AGENT_UNSYNCED anymore.
Mark it as DEPRECATED.

Signed-off-by: Chen Hanxiao <chenhanxiao@gmail.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-12-07 14:30:20 +01:00
Erik Skultety
b08017ca54 maint: Replace tabs with spaces in all source files in repo
So we have a syntax-check rule to catch all tab indents but it naturally
can't catch tab spacing, i.e. as a delimiter. This patch is a result of
running 'vim -en +retab +wq'
(using tabstop=8 softtabstop=4 shiftwidth=4 expandtab) on each file from
a list generated by the following:
find . -regextype gnu-awk \
         -regex ".*\.(rng|syms|html|s?[ch]|py|pl|php(\.code)?)(\.in)?" \
         | xargs git grep -lP "\t"

Signed-off-by: Erik Skultety <eskultet@redhat.com>
2017-10-18 13:25:10 +02:00
Martin Kletzander
af4270400a Move resctrl-related code from conf/capabilities to util/virresctrl
It doesn't access anything from conf/ and ti will be needed to use
from other util/ places.  This split makes the separation clearer.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2017-08-14 10:01:12 +02:00
Pino Toscano
f0e7f90bff virerror: add error for libssh transport
Add a new error domain and number for a new libssh-based transport.
2016-11-15 15:50:51 +01:00
Yuri Pudgorodskiy
914d5e1cbf qemu: guest agent: introduce new error code VIR_ERR_AGENT_UNSYNCED
A separate error code will help recognize real failures from
necessity to try again

Signed-off-by: Maxim Nestratov <mnestratov@virtuozzo.com>
2016-09-07 12:35:18 +03:00
Erik Skultety
52a2eef948 admin: Introduce virAdmServerLookupClient
Just like with server-related APIs, before any of client-based APIs can be
called, a reference to a client-side client object needs to be obtained. For
this purpose, a lookup method should exist. Apart from the client retrieval
logic, a new error code for non-existent client had to be added as well.

Signed-off-by: Erik Skultety <eskultet@redhat.com>
2016-05-03 15:52:50 +02:00
Qiaowei Ren
28b446292b perf: implement a set of util functions for perf event
This patch implement a set of interfaces for perf event. Based on
these interfaces, we can implement internal driver API for perf,
and get the results of perf conuter you care about.

Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>
Message-id: 1459171833-26416-4-git-send-email-qiaowei.ren@intel.com
2016-03-29 13:13:05 +01:00
Martin Kletzander
62be54861b virerror: Introduce new error type NO_SERVER
This serves the same purpose as VIR_ERR_NO_xxx where xxx is any object
that API can be called upon.  Only this particular one is used for
daemon's servers.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2016-03-11 12:58:41 +01:00
John Ferlan
1d35f6ffe1 polkit: Adjust message when authentication agent isn't found
When there isn't a ssh -X type session running and a user has not
been added to the libvirt group, attempts to run 'virsh -c qemu:///system'
commands from an otherwise unprivileged user will fail with rather
generic or opaque error message:

    "error: authentication failed: no agent is available to authenticate"

This patch will adjust the error code and message to help reflect the
situation that the problem is the requested mechanism is UNAVAILABLE and
a slightly more descriptive error. The result on a failure then becomes:

    "error: authentication unavailable: no polkit agent available to
            authenticate action 'org.libvirt.unix.manage'"

A bit more history on this - at one time a failure generated the
following type message when running the 'pkcheck' as a subprocess:

"error: authentication failed: polkit\56retains_authorization_after_challenge=1
Authorization requires authentication but no agent is available."

but, a patch was generated to adjust the error message to help provide
more details about what failed. This was pushed as commit id '96a108c99'.
That patch prepended a "polkit: " to the output. It really didn't solve
the problem, but gave a hint.

After some time it was deemed using DBus API calls directly was a
better way to go (since pkcheck calls them anyway). So, commit id
'1b854c76' (more or less) copied the code from remoteDispatchAuthPolkit
and adjusted it. Then commit id 'c7542573' adjusted the remote.c
code to call the new API (virPolkitCheckAuth). Finally, commit id
'308c0c5a' altered the code to call DBus APIs directly. In doing
so, it reverted the failing error message to the generic message
that would have been received from DBus anyway.
2016-03-01 06:50:16 -05:00
Jim Fehlig
8c3c32f16a Xen: add XENXL to virErrorDomain enum
Add "Xen XL Config" to the virErrorDomain enum and use it in
src/xenconfig/xen_xl.c.
2016-01-21 09:31:39 -07:00
Daniel P. Berrange
323a329b26 Import stripped down virtlockd code as basis of virtlogd
Copy the virtlockd codebase across to form the initial virlogd
code. Simple search & replace of s/lock/log/ and gut the remote
protocol & dispatcher. This gives us a daemon that starts up
and listens for connections, but does nothing with them.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-11-26 14:28:55 +00:00
Jiri Denemark
44c42b564d qemu: Don't report false error from MigrateFinish
virDomainMigrateFinish* APIs were unfortunately designed to return the
pointer to the domain on destination and NULL on error. This looks OK in
normal cases but the same API is also called when we know migration
failed and thus we expect Finish to return NULL even if it actually did
all it was supposed to do without any error. The call is defined to
return nonnull domain pointer over RPC, which means returning NULL will
always result in an error being send. If this was not in fact an error,
the API itself wouldn't set anything to the thread local virError, which
makes the RPC layer come up with it's own "Library function returned
error but did not set virError" error.

This is quite confusing and also hard to detect by the caller. This
patch adds a special error code which can be used to check that Finish
successfully aborted migration.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2015-07-10 11:47:13 +02:00
Martin Kletzander
653acbfd62 Add admin error domain
Just the addition of VIR_FROM_ADMIN to the enum of error domains.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2015-06-16 13:46:20 +02:00
Jiri Denemark
956953884e Add support for tracking thread jobs
Each thread can use a thread local variable to keep the name of a job
which is currently running in the job.

The virThreadJobSetWorker API is supposed to be called once by any
thread which is used as a worker, i.e., it is waiting in a pool, woken
up to do a job, and returned back to the pool.

The virThreadJobSet/virThreadJobClear APIs are to be called at the
beginning/end of each job.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2015-03-25 10:00:53 +01:00
Martin Kletzander
0e7457e501 Fix common misspellings
Wikipedia's list of common misspellings [1] has a machine-readable
version.  This patch fixes those misspellings mentioned in the list
which don't have multiple right variants (as e.g. "accension", which can
be both "accession" and "ascension"), such misspellings are left
untouched.  The list of changes was manually re-checked for false
positives.

[1] https://en.wikipedia.org/wiki/Wikipedia:Lists_of_common_misspellings/For_machines

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2015-03-23 09:01:30 +01:00
Daniel P. Berrange
6d06b0d89b Add virXMLValidateAgainstSchema helper method
Add a helper method that can validate an XML document against
an RNG schema
2015-01-15 14:02:50 +00:00
Daniel P. Berrange
1b854c76c7 Add common API for doing polkit authentication
There are now two places in libvirt which use polkit. Currently
they use pkexec, which is set to be replaced by direct DBus API
calls. Add a common API which they will both be able to use for
this purpose.

No tests are added at this time, since the impl will be gutted
in favour of a DBus API call shortly.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-09-24 15:29:22 +01:00
Jiri Denemark
b14954fc12 cpuCompare*: Add support for reporting failure on incompatible CPUs
When CPU comparison APIs return VIR_CPU_COMPARE_INCOMPATIBLE, the caller
has no clue why the CPU is considered incompatible with host CPU. And in
some cases, it would be nice to be able to get such info in a client
rather than having to look in logs.

To achieve this, the APIs can be told to return VIR_ERR_CPU_INCOMPATIBLE
error for incompatible CPUs and the reason will be described in the
associated error message.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-06-26 00:43:54 +02:00
Daniel P. Berrange
3a0ca7de51 Introduce an object for managing firewall rulesets
The network and nwfilter drivers both have a need to update
firewall rules. The currently share no code for interacting
with iptables / firewalld. The nwfilter driver is fairly
tied to the concept of creating shell scripts to execute
which makes it very hard to port to talk to firewalld via
DBus APIs.

This patch introduces a virFirewallPtr object which is able
to represent a complete sequence of rule changes, with the
ability to have multiple transactional checkpoints with
rollbacks. By formally separating the definition of the rules
to be applied from the mechanism used to apply them, it is
also possible to write a firewall engine that uses firewalld
DBus APIs natively instead of via the slow firewalld-cmd.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-04-25 15:44:09 +01:00
Daniel P. Berrange
3a7fe8d508 Add helper APIs for generating cryptographic hashes
GNULIB provides APIs for calculating md5 and sha256 hashes,
but these APIs only return you raw byte arrays. Most users
in libvirt want the hash in printable string format. Add
some helper APIs in util/vircrypto.{c,h} for doing this.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-03-10 16:39:18 +00:00
Roman Bogorodskiy
0eb4a5f4f1 bhyve: add a basic driver
At this point it has a limited functionality and is highly
experimental. Supported domain operations are:

  * define
  * start
  * destroy
  * dumpxml
  * dominfo

It's only possible to have only one disk device and only one
network, which should be of type bridge.
2014-02-19 14:21:50 +00:00
Michal Privoznik
4b744d7d00 virerror: s/VIR_ERR_STORAGE_VOL_EXISTS/VIR_ERR_STORAGE_VOL_EXISTS/
We currently have other error codes in singular form, e.g.
VIR_ERR_NETWORK_EXIST. Cleanup the previous patch to match the form.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2013-10-07 19:21:47 +02:00
Hongwei Bi
91875896d5 fix a ambiguous output of the command:'virsh vol-create-as'
I created a storage volume(eg: test) from a storage pool(eg:vg10) using
the following command:"virsh vol-create-as --pool vg10 --name test --capacity 300M."
When I re-executed the above command, the output was as the following:
"error: Failed to create vol test
 error: Storage volume not found: storage vol 'test' already exists"

I think the output "Storage volume not found" is not appropriate. Because in fact storage
vol test has been found at this time. And then I think virErrorNumber should includes
VIR_ERR_STORAGE_EXIST which can also be used elsewhere. So I make this patch. The result
is as following:
"error: Failed to create vol test
 error: storage volume 'test' exists already"
2013-10-07 18:26:09 +02:00
Daniel P. Berrange
dff93f8cab Add API for calling systemd-machined's DBus API
To register virtual machines and containers with systemd-machined,
and thus have cgroups auto-created, we need to talk over DBus.
This is somewhat tedious code, so introduce a dedicated function
to isolate the DBus call in one place.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-22 13:09:58 +01:00
Daniel P. Berrange
834c9c9459 Introduce virDBusCallMethod & virDBusMessageRead methods
Doing DBus method calls using libdbus.so is tedious in the
extreme. systemd developers came up with a nice high level
API for DBus method calls (sd_bus_call_method). While
systemd doesn't use libdbus.so, their API design can easily
be ported to libdbus.so.

This patch thus introduces methods virDBusCallMethod &
virDBusMessageRead, which are based on the code used for
sd_bus_call_method and sd_bus_message_read. This code in
systemd is under the LGPLv2+, so we're license compatible.

This code is probably pretty unintelligible unless you are
familiar with the DBus type system. So I added some API
docs trying to explain how to use them, as well as test
cases to validate that I didn't screw up the adaptation
from the original systemd code.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-22 13:09:58 +01:00
Daniel P. Berrange
a93cd08fd5 Define basic internal API for access control
This patch introduces the virAccessManagerPtr class as the
interface between virtualization drivers and the access
control drivers. The viraccessperm.h file defines the
various permissions that will be used for each type of object
libvirt manages

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-06-24 15:24:36 +01:00
Daniel P. Berrange
69c6a58a1d Add a virGetLastErrorMessage() function
Apps using libvirt will often have code like

   if (virXXXX() < 0) {
      virErrorPtr err = virGetLastError();
      fprintf(stderr, "Something failed: %s\n",
              err && err->message ? err->message :
              "unknown error");
      return -1;
   }

Checking for a NULL error object or message leads to very
verbose code. A virGetLastErrorMessage() helper from libvirt
can simplify this to

   if (virXXXX() < 0) {
      fprintf(stderr, "Something failed: %s\n",
              virGetLastErrorMessage());
      return -1;
   }

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-05-10 19:57:18 +01:00
Daniel P. Berrange
1da631ecf3 Add an API for re-mounting cgroups, to isolate the process location
Add a virCgroupIsolateMount method which looks at where the
current process is place in the cgroups (eg /system/demo.lxc.libvirt)
and then remounts the cgroups such that this sub-directory
becomes the root directory from the current process' POV.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-15 17:35:32 +01:00
Daniel P. Berrange
3aabe27247 Define internal APIs for managing identities
Introduce a local object virIdentity for managing security
attributes used to form a client application's identity.
Instances of this object are intended to be used as if they
were immutable, once created & populated with attributes

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-19 13:37:37 +00:00
Daniel P. Berrange
c4ef575c97 Add APIs for talking to init via /dev/initctl
To be able todo controlled shutdown/reboot of containers an
API to talk to init via /dev/initctl is required. Fortunately
this is quite straightforward to implement, and is supported
by both sysvinit and systemd. Upstart support for /dev/initctl
is unclear.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2012-11-30 19:17:30 +00:00
Daniel P. Berrange
eca72d4759 Introduce an internal API for handling file based lockspaces
The previously introduced virFile{Lock,Unlock} APIs provide a
way to acquire/release fcntl() locks on individual files. For
unknown reason though, the POSIX spec says that fcntl() locks
are released when *any* file handle referring to the same path
is closed. In the following sequence

  threadA: fd1 = open("foo")
  threadB: fd2 = open("foo")
  threadA: virFileLock(fd1)
  threadB: virFileLock(fd2)
  threadB: close(fd2)

you'd expect threadA to come out holding a lock on 'foo', and
indeed it does hold a lock for a very short time. Unfortunately
when threadB does close(fd2) this releases the lock associated
with fd1. For the current libvirt use case for virFileLock -
pidfiles - this doesn't matter since the lock is acquired
at startup while single threaded an never released until
exit.

To provide a more generally useful API though, it is necessary
to introduce a slightly higher level abstraction, which is to
be referred to as a "lockspace".  This is to be provided by
a virLockSpacePtr object in src/util/virlockspace.{c,h}. The
core idea is that the lockspace keeps track of what files are
already open+locked. This means that when a 2nd thread comes
along and tries to acquire a lock, it doesn't end up opening
and closing a new FD. The lockspace just checks the current
list of held locks and immediately returns VIR_ERR_RESOURCE_BUSY.

NB, the API as it stands is designed on the basis that the
files being locked are not being otherwise opened and used
by the application code. One approach to using this API is to
acquire locks based on a hash of the filepath.

eg to lock /var/lib/libvirt/images/foo.img the application
might do

   virLockSpacePtr lockspace = virLockSpaceNew("/var/lib/libvirt/imagelocks");
   lockname = md5sum("/var/lib/libvirt/images/foo.img");
   virLockSpaceAcquireLock(lockspace, lockname);

NB, in this example, the caller should ensure that the path
is canonicalized before calculating the checksum.

It is also possible to do locks directly on resources by
using a NULL lockspace directory and then using the file
path as the lock name eg

   virLockSpacePtr lockspace = virLockSpaceNew(NULL);
   virLockSpaceAcquireLock(lockspace, "/var/lib/libvirt/images/foo.img");

This is only safe to do though if no other part of the process
will be opening the files. This will be the case when this
code is used inside the soon-to-be-reposted virlockd daemon

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2012-10-16 15:45:55 +01:00
Eric Blake
4ecb723b9e maint: fix up copyright notice inconsistencies
https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.

* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/;  If/.  If/
2012-09-20 16:30:55 -06:00
Michal Privoznik
aa3e8bd4ca Introduce new VIR_ERR_AGENT_UNRESPONSIVE error code
Currently, when guest agent is configured but not responsive
(e.g. due to appropriate service not running in the guest)
we return VIR_ERR_INTERNAL_ERROR. Both are wrong. Therefore
we need to introduce new error code to reflect this case.
2012-08-27 18:00:10 +02:00