Commit Graph

11999 Commits

Author SHA1 Message Date
Daniel P. Berrange
3bab69c30f libxl: Move virDomainXMLOptionNew into libxlCreateXMLConf
To allow the test suite to creat the XML option object,
move the virDomainXMLOptionNew call into a libxlCreateXMLConf
method.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-06-03 11:45:59 +01:00
Daniel P. Berrange
a6abdbf645 libxl: Don't pass libxlDriverPrivatePtr into libxlBuildDomainConfig
To make it easier to test, change libxlBuildDomainConfig so
that it takes a virPortAllocatorPtr instead of the larger
libxlDriverPrivatePtr object.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-06-03 11:45:59 +01:00
Daniel P. Berrange
5da28f2405 libxl: Don't pass virDomainObjPtr to libxlBuildDomainConfig
To make it easier to unit test, change libxlBuildDomainConfig
so that it takes 'virDomainDefPtr' and 'libxl_ctx *' objects
as separate parameters.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-06-03 11:45:59 +01:00
Jiri Denemark
5bf670323e qemu: Return in from qemuDomainRemove*Device
Some of the APIs already return int since they can produce errors that
need to be propagated. For consistency reasons, this patch changes the
rest of the APIs to also return int even though they do not fail or
report any errors.
2014-06-03 10:58:07 +02:00
Jiri Denemark
55b21f9b23 qemu: Remove character device backend only after frontend is gone
In general, we should only remove a backend after seeing DEVICE_DELETED
event for a corresponding frontend.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-06-03 10:58:07 +02:00
Jiri Denemark
0635785b6e qemu: Remove disk backend only after frontend is gone
In general, we should only remove a backend after seeing DEVICE_DELETED
event for a corresponding frontend. This doesn't make any difference for
disks attached using -drive or drive_add since QEMU automatically
removes their backends but it's still better to make our code
consistent. And it may start making difference in case we switch to
attaching disks using -blockdev.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-06-03 10:58:06 +02:00
Jiri Denemark
81f765985e qemu: Remove interface backend only after frontend is gone
[1] reported that we are removing network's backend too early. I didn't
really get the reproducer but libvirt behaves strangely when a guest
does not confirm the removal, e.g., it does not support PCI hotplug. In
such case, detaching a network device leaves its frontend in place but
removes the backend, which makes the device unusable for the guest.
Moreover attaching the same device again succeeds and both the guest and
libvirt will see two network interfaces attached but only one of them is
actually working.

I checked with Paolo Bonzini and he confirmed we should only remove a
backend after seeing DEVICE_DELETED event for a corresponding frontend.

[1] https://www.redhat.com/archives/libvir-list/2014-March/msg01740.html

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-06-03 10:58:06 +02:00
Peter Krempa
f744b831c6 qemu: json: Add format strings for optional command arguments
This patch adds option to specify that a json qemu command argument is
optional without the need to use if's or ternary operators to pass the
list. Additionally all the modifier characters are documented to avoid
user confusion.
2014-06-03 09:47:13 +02:00
Peter Krempa
682267496b util: string: Return element count from virStringSplit
To allow using the array manipulation macros on the arrays returned by
virStringSplit we need to know the count of the elements in the array.
Modify virStringSplit to return this value, rename it and add a helper
with the old name so that we don't need to update all the code.
2014-06-03 09:27:24 +02:00
Peter Krempa
1423ae296f storage: Traverse backing chains of network disks
Now we don't need to skip backing chain detection for remote disks.
2014-06-03 09:27:24 +02:00
Peter Krempa
b225444e25 storage: Change to new backing store parser
Use the new backing store parser in the backing chain crawler. This
change needs one test change where information about the NBD image are
now parsed differently.
2014-06-03 09:27:24 +02:00
Peter Krempa
ed68eb8628 storage: Add infrastructure to parse remote network backing names
Add parsers for relative and absolute backing names for local and remote
storage files.

This parser parses relative paths as relative to their parents and
absolute paths according to the protocol or local access.

For remote storage volumes, all URI based backing file names are
supported and for the qemu colon syntax the NBD protocol is supported.
2014-06-03 09:27:24 +02:00
Peter Krempa
6cdff20c2a storage: Switch metadata crawler to use storage driver file access check
Use virStorageFileAccess() to to check whether the file is accessible in
the main part of the metadata crawler.
2014-06-03 09:27:23 +02:00
Peter Krempa
2bdb8b965b storage: Switch metadata crawler to use storage driver to read headers
Use virStorageFileReadHeader() to read headers of storage files possibly
on remote storage to retrieve the image metadata.

The backend information is now parsed by
virStorageFileGetMetadataInternal which is now exported from the util
source and virStorageFileGetMetadataFromFDInternal now doesn't need to
be exported.
2014-06-03 09:27:23 +02:00
Peter Krempa
395171f87f storage: Switch metadata crawler to use storage driver to get unique path
Use the virStorageFileGetUniqueIdentifier() function to get a unique
identifier regardless of the target storage type instead of relying on
canonicalize_path().

A new function that checks whether we support a given image is
introduced to avoid errors for unimplemented backends.
2014-06-03 09:27:23 +02:00
Peter Krempa
edfd6127c1 storage: backend: Add possibility to suppress errors from backend lookup
Add a new function wrapper and tweak the storage file backend lookup
function so that it can be used without reporting error. This will be
useful in the metadata crawler code where we need silently break if
metadata retrieval is not supported for the current storage type.
2014-06-03 09:27:23 +02:00
Peter Krempa
d4c0ceae1b storage: Determine the local storage type right away
When walking the backing chain we previously set the storage type to
_FILE and let the virStorageFileGetMetadataFromFDInternal update it to
the correct type later on.

This patch moves the actual storage type determination to the place
where we parse the backing store name so that the code can later be
switched to use virStorageFileReadHeader() directly.
2014-06-03 09:27:23 +02:00
Peter Krempa
713cc3b0a7 storage: Move virStorageFileGetMetadata to the storage driver
My future work will modify the metadata crawler function to use the
storage driver file APIs to access the files instead of accessing them
directly so that we will be able to request the metadata for remote
files too. To avoid linking the storage driver to every helper file
using the utils code, the backing chain traversal function needs to be
moved to the storage driver source.

Additionally the virt-aa-helper and virstoragetest programs need to be
linked with the storage driver as a result of this change.
2014-06-03 09:27:23 +02:00
Peter Krempa
4cb2505557 storage: Add API to check accessibility of storage volumes
Add a storage driver API equivalent of the access() function.
Implementations for the filesystem and gluster backends are provided.
2014-06-03 09:27:23 +02:00
Peter Krempa
684ec651e9 storage: backend: Add unique id retrieval API
Different protocols have different means to uniquely identify a storage
file. This patch implements a storage driver API to retrieve a unique
string describing a volume. The current implementation works for local
storage only and returns the canonical path of the volume.

To add caching support the local filesystem driver now has a private
structure holding the cached string, which is created only when it's
initially accessed.

This patch provides the implementation for local files only for start.
2014-06-03 09:27:22 +02:00
Michal Privoznik
b20060bae2 xenapi_utils: Adapt to enum cleanups
It was just very recently that we transfered from:

  enum virSomeEnumName{
      ...
  };

to:
  typedef enum {
      ...
  } virSomeEnumName;

This change requires some code adaptation, which wasn't done for
xenapi driver. With this fix we are able to build again.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-06-03 09:18:58 +02:00
Michal Privoznik
3dd23b6106 virnuma.c: Fix some comments
In 9dd02965 the virNumaGetNodeMemory was introduced, however the
comment describing the function mentions virNumaGetNodeMemorySize.
And there's one typo in virNumaIsAvailable() description.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-06-03 08:58:24 +02:00
Julio Faracco
5a2bd4c917 conf: more enum cleanups in "src/conf/domain_conf.h"
In "src/conf/domain_conf.h" there are many enum declarations. The
cleanup in this header filer was started, but it wasn't enough and
there are many other files that has enum variables declared. So, the
commit was starting to be big. This commit finish the cleanup in this
header file and in other files that has enum variables, parameters,
or functions declared.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2014-06-02 15:32:58 -06:00
Julio Faracco
d4dad16204 conf: enum cleanups in "src/conf/domain_conf.h"
In "src/conf/domain_conf.h" there are many enumerations (enum)
declarations to be converted as a typedef too. As mentioned before,
it's better to use a typedef for variable types, function types and
other usages. I think this file has most of those enum declarations
at "src/conf/". So, me and Eric Blake plan to keep the cleanups all
over the source code. This time, most of the files changed in this
commit are related to part of one file: "src/conf/domain_conf.h".

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
2014-06-02 15:20:22 -06:00
Julio Faracco
5443b15829 cpu: use typedefs for enums in "src/cpu/cpu_map.h"
In "src/cpu/" there are some enumerations (enum) declarations.
Similar to the recent cleanup to "src/util", "src/conf" and other
directories, it's better to use a typedef for variable types,
function types and other usages. Other enumeration and folders will
be changed to typedef's in the future. Specially, in files that are
in different places of "src/util" and "src/conf". Most of the files
changed in this commit are related to CPU (cpu_map.h) enums.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
2014-06-02 15:15:05 -06:00
Ján Tomko
819ca36e2b Don't use AI_ADDRCONFIG when binding to wildcard addresses
https://bugzilla.redhat.com/show_bug.cgi?id=1098659

With parallel boot, network addresses might not yet be assigned [1],
but binding to wildcard addresses should work.

For non-wildcard addresses, ADDRCONFIG is still used. Document this
in libvirtd.conf.

[1] http://www.freedesktop.org/wiki/Software/systemd/NetworkTarget/
2014-06-02 17:12:01 +02:00
Jiri Denemark
25a5df16a6 qemu: Unref cfg when detaching hostdev interface
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-06-02 16:47:36 +02:00
Jiri Denemark
47f424c2d9 qemu: Process DEVICE_DELETED event in a separate thread
Currently, we don not acquire any job when removing a device after
DEVICE_DELETED event was received from QEMU. This means that if there is
another API running at the time DEVICE_DELETED is delivered and the API
acquired a job, we may happily change the definition of the domain the
API is working with whenever it unlocks the domain object (e.g., to talk
with its monitor). That said, we have to acquire a job before finishing
device removal to make things safe. However, doing so in the main event
loop would cause a deadlock so we need to move most of the event handler
into a separate thread.

Another good reason for both acquiring a job and handling the event in a
separate thread is that we currently remove a device backend immediately
after removing its frontend while we should only remove the backend once
we already received DEVICE_DELETED event. That is, we will have to talk
to QEMU monitor from the event handler.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-06-02 16:47:36 +02:00
Jiri Denemark
4670f1dd02 qemu: Finish device removal in the original thread
If QEMU supports DEVICE_DELETED event, we always call
qemuDomainRemoveDevice from the event handler. However, we will need to
push this call away from the main event loop and begin a job for it (see
the following commit), we need to make sure the device is fully removed
by the original thread (and within its existing job) in case the
DEVICE_DELETED event arrives before qemuDomainWaitForDeviceRemoval times
out.

Without this patch, device removals would be guaranteed to never finish
before the timeout because the could would be blocked by the original
job being still active.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-06-02 16:47:36 +02:00
Pavel Hrdina
f8a0c9edf0 Fix build on freebsd
On freebsd there isn't known "setlocale" so we have to include locale.h
2014-06-02 16:45:42 +02:00
Nehal J Wani
baafe668fa Add helper program to create custom leases
Introduce helper program to catch events from dnsmasq and maintain a custom
lease file per network. It supports dhcpv4 and dhcpv6. The file is saved as
"<interface-name>.status".

Each lease contains the following info:
<expiry-time (epoch time)> <mac> <iaid> <ip-address> <hostname> <clientid>

Example of custom leases file content:
[
    {
        "iaid": "1221229",
        "ip-address": "2001:db8:ca2:2:1::95",
        "mac-address": "52:54:00:12:a2:6d",
        "hostname": "Fedora20",
        "client-id": "00:04:1a:c1:d9:6b:5a:0a:e2:bc:f8:4b:1e:37:2e:38:22:55",
        "expiry-time": 1393244216
    },
    {
        "ip-address": "192.168.150.208",
        "mac-address": "52:54:00:11:56:b3",
        "hostname": "Wani-PC",
        "client-id": "01:52:54:00:11:56:b3",
        "expiry-time": 1393244248
    }
]

src/Makefile.am:
   * Add options to compile the helper program

src/network/bridge_driver.c:
   * Introduce networkDnsmasqLeaseFileNameCustom()
   * Invoke helper program along with dnsmasq
   * Delete the .status file when corresponding n/w is destroyed.

src/network/leaseshelper.c
   * Helper program to create the custom lease file
2014-06-02 11:45:10 +01:00
Peter Krempa
23f38f8813 qemu: snapshot: Improve detection of mixed snapshots
Currently we don't support mixed (external + internal) snapshots. The
code detecting the snapshot type didn't make sure that the memory image
was consistent with the snapshot type leading into strange error
message:

 $ virsh snapshot-create-as --domain VM --diskspec vda,snapshot=internal --memspec snapshot=external,file=/tmp/blah
 error: internal error: unexpected code path

Fix the mixed detection code to detect this kind of mistake:

 $ virsh snapshot-create-as --domain VM --diskspec vda,snapshot=internal --memspec snapshot=external,file=/tmp/blah
 error: unsupported configuration: mixing internal and external targets for a snapshot is not yet supported
2014-05-29 17:00:11 +02:00
Peter Krempa
d2e668e535 qemu: snapshot: Reject internal active snapshot without memory state
A internal snapshot of a active VM with the memory snapshot disabled
explicitly would actually still take the memory snapshot. Reject it
explicitly.

Before:
 $ virsh snapshot-create-as --domain VM --diskspec vda,snapshot=internal --memspec snapshot=no
 Domain snapshot 1401353155 created

After:
 $ virsh snapshot-create-as --domain VM --diskspec vda,snapshot=internal --memspec snapshot=no
 error: Operation not supported: internal snapshot of a running VM must include the memory state

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1083345
2014-05-29 17:00:11 +02:00
Peter Krempa
4a051b807e util: storage: Fix crash of libvirtd on network backed guest block-pull
For guests backed by gluster volumes (or other network storage) we don't
fill the backing chain (see qemuDomainDetermineDiskChain). This leaves
the "relPath" field of the top image NULL. This causes a crash in
virStorageFileChainLookup() when looking up a backing element for such a
disk.

Since I'm working on adding support for network storage and one of the
steps will make the "relPath" field optional let's use STREQ_NULLABLE
instead of STREQ in virStorageFileChainLookup() to avoid the problem.
2014-05-29 16:51:05 +02:00
Laine Stump
26d43113a3 util: fix virTimeLocalOffsetFromUTC DST processing
The original version of virTimeLocalOffsetFromUTC() would fail for
certain times of the day if daylight savings time was active. This
could most easily be seen by uncommenting the TEST_LOCALOFFSET() cases
that include a DST setting.

After a lot of experimenting, I found that the way to solve it in
almost all test cases is to set tm_isdst = -1 in the struct tm prior
to calling mktime(). Once this is done, the correct offset is returned
for all test cases at all times except the two hours just after
00:00:00 Jan 1 UTC - during that time, any timezone that is *behind*
UTC, and that is supposed to always be in DST will not have DST
accounted for in its offset.

I believe that the code of virTimeLocalOffsetFromUTC() actually is
correct for all cases, but the problem still encountered is due to our
inability to come up with a TZ string that properly forces DST to
*always* be active. Since a modfication of the (currently fixed)
expected result data to account for this would necessarily use the
same functions that we're trying to test, I've instead just made the
test program conditionally bypass the problematic cases if the current
date is either December 31 or January 1. This way we get maximum
testing during 363 days of the year, but don't get false failures on
Dec 31 and Jan 1.
2014-05-29 10:37:49 +03:00
Peter Krempa
0b317d61fc qemu: managedsave: Don't spam logs with warnings about corrupted image
Even successful start of a VM from a managed save image would spam the
logs with the following message:

Unable to restore from managed state [path]. Maybe the file is
corrupted?

Re-arrange the logic to output the warning only when the image is
corrupted.

The flaw was introduced in commit cfc28c66.
2014-05-28 19:27:27 +02:00
Peter Krempa
92dc2dabb3 utils: storage: Canonicalize paths only for local filesystems
Now that virStorageFileGetMetadataFromBuf is used only for remote
filesystems, don't canonicalize the path in it.
2014-05-28 19:23:36 +02:00
Peter Krempa
34d86185ec storage: fs: Drop-in replace use of virStorageFileGetMetadataFromBuf
Use virStorageFileGetMetadataFromFD instead in
virStorageBackendProbeTarget as it now returns all required data and the
storage file is already open in a filedescriptor.

Also fix improper error code being returned when virFileReadHeaderFD
would fail as virStorageBackendUpdateVolTargetInfoFD would set the
return code to 0.
2014-05-28 19:23:35 +02:00
Peter Krempa
5a1cf6bd16 storage: Return backing format from virStorageFileGetMetadataFromFD
Add argument to return backing file format of a file probed by
virStorageFileGetMetadataFromFD so that it can be used in place of
virStorageFileGetMetadataFromBuf.
2014-05-28 19:23:35 +02:00
Eric Blake
e6bcbcd32c qemu: reject rather than hang on blockcommit of active layer
qemu 2.0 added the ability to commit the active layer, but slightly
differently than what libvirt had been anticipating in its
implementation of the virDomainBlockCommit call.  As a result, if
you attempt to do a 'virsh blockcommit $dom vda', qemu gets into a
state where it is waiting on libvirt to end the job, while libvirt
is waiting on qemu to end the job, and the guest is effectively
hung with regards to further commands for that block device.

I have patches coming down the pipeline that will add full support
for blockcommit of the active layer when coupled with qemu 2.0 or
later; but they depend on Peter's improvements to block job handling
and form enough of a new feature that they are not ready for
inclusion in the 1.2.5 release.  So for now, just reject the
attempt, rather than letting the user get stuck.  This is no worse
than the behavior of qemu 1.7 rejecting the job.

* src/qemu/qemu_driver.c (qemuDomainBlockCommit): Reject active
commit.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-05-28 10:41:58 -06:00
Dan Kenigsberg
110be4112f doc: fix documentation of virDomainSet(Get)Metadata
The documentation of the functions should match the argument name in the actual
function signature.

Signed-off-by: Dan Kenigsberg <danken@redhat.com>
2014-05-28 13:23:11 +02:00
Olivia Yin
fd0f22ed41 qemu: Fix specifying char devs for PPC
QEMU ppce500 board uses the legacy -serial option.

Other PPC boards don't give any way to explicitly wire in a -chardev
except pseries which uses -device spapr-vty with -chardev.

Add test case for -serial option for ppce500

Signed-off-by: Olivia Yin <Hong-Hua.Yin@freescale.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2014-05-27 08:48:57 +02:00
Daniel Veillard
f07d24a6b8 Fix an extra ' in a translated string
Raised by ukrainian translator Yuri Chornoivan
https://fedora.transifex.com/projects/p/libvirt/translate/#uk/strings/25483059
2014-05-26 21:51:26 +08:00
Ján Tomko
205010c40e Clean up chardev sockets on QEMU shutdown
https://bugzilla.redhat.com/show_bug.cgi?id=1088787

Clean up unix socket files for chardevs using mode='bind',
like we clean up the monitor socket.
They are created by QEMU on startup and not really useful
after shutting it down.
2014-05-26 15:17:54 +02:00
Laine Stump
cde8ca2dfd qemu: fix <clock offset='variable' basis='localtime'/>
For a clock element as above, libvirt simply converts current system
time with localtime_r(), then starts qemu with a time string that
doesn't contain any timezone information. So, from qemu's point of
view, the -rtc string it gets for:

   <clock offset='variable' basis='utc' adjustment='10800'/>

is identical to the -rtc string it gets for:

   <clock offset='variable' basis='localtime' adjustment='0'/>

(assuming the host is in a timezone that is 10800 seconds ahead of
UTC, as is the case on the machine where this message is being
written).

Since the commandlines are identical, qemu will behave identically
after this point in either case.

There are two problems in the case of basis='localtime' though:

Problem 1) If the guest modifies its RTC, for example to add 20
seconds, the RTC_CHANGE event from qemu will then contain offset:20 in
both cases. But libvirt will have saved the original adjustment into
adjustment0, and will add that value onto the offset in the
event. This means that in the case of basis=;utc', it will properly
emit an event with offset:10820, but in the case of basis='localtime'
the event will contain offset:20, which is *not* the new offset of the
RTC from UTC (as the event it documented to provide).

Problem 2) If the guest is migrated to another host that is in a
different timezone, or if it is migrated or saved/restored after the
DST status has changed from what it was when the guest was originally
started, the newly restarted guest will have a different RTC (since it
will be based on the new localtime, which could have shifted by
several hours).

The solution to both of these problems is simple - rather than
maintaining the original adjustment value along with
"basis='localtime'" in the domain status, when the domain is started
we convert the adjustment offset to one relative to UTC, and set the
status to "basis='utc'". Thus, whatever the RTC offset was from UTC
when it was initially started, that offset will be maintained when
migrating across timezones and DST settings, and the RTC_CHANGE events
will automatically contain the proper offset (which should by
definition always be relative to UTC).

This fixes a problem that was implied but not openly stated in:

  https://bugzilla.redhat.com/show_bug.cgi?id=964177
2014-05-26 13:59:32 +03:00
Laine Stump
b62d67da3e qemu: fix RTC_CHANGE event for <clock offset='variable' basis='utc'/>
commit e31b5cf393 attempted to fix libvirt's
VIR_DOMAIN_EVENT_ID_RTC_CHANGE, which is documentated to always
provide the new offset of the domain's real time clock from UTC. The
problem was that, in the case that qemu is provided with an "-rtc
base=x" where x is an absolute time (rather than "utc" or
"localtime"), the offset sent by qemu's RTC_CHANGE event is *not* the
new offset from UTC, but rather is the sum of all changes to the
domain's RTC since it was started with base=x.

So, despite what was said in commit e31b5cf393, if we assume that
the original value stored in "adjustment" was the offset from UTC at
the time the domain was started, we can always determine the current
offset from UTC by simply adding the most recent (i.e. current) offset
from qemu to that original adjustment.

This patch accomplishes that by storing the initial adjustment in the
domain's status as "adjustment0". Each time a new RTC_CHANGE event is
received from qemu, we simply add adjustment0 to the value sent by
qemu, store that as the new adjustment, and forward that value on to
any event handler.

This patch (*not* e31b5cf393, which should be reverted prior to
applying this patch) fixes:

https://bugzilla.redhat.com/show_bug.cgi?id=964177

(for the case where basis='utc'. It does not fix basis='localtime')
2014-05-26 13:58:09 +03:00
Laine Stump
b8efa6f2e3 Revert "qemu: Report the offset from host UTC for RTC_CHANGE event"
This reverts commit e31b5cf393.

This commit attempted to work around a bug in the offset value
reported by qemu's RTC_CHANGE event in the case that a variable base
date was given on the qemu commandline. The patch mixed up the math
involved in arriving at the corrected offset to report, and in the
process added an unnecessary private attribute to the clock
element. Since that element is private/internal and not used by anyone
else, it makes sense to simplify things by removing it.
2014-05-26 13:53:16 +03:00
Laine Stump
1cddaea7ae util: new function virTimeLocalOffsetFromUTC
Since there isn't a single libc API to get this value, this patch
supplies one which gets the value by grabbing current time, then
converting that into a struct tm with gmtime_r(), then back to a
time_t using mktime.

The returned value is the difference between UTC and localtime in
seconds. If localtime is ahead of UTC (east) the offset will be a
positive number, and if localtime is behind UTC (west) the offset will
be negative.

This function should be POSIX-compliant, and is threadsafe, but not
async signal safe. If it was ever necessary to know this value in a
child process, we could cache it with a one-time init function when
libvirtd starts, then just supply the cached value, but that
complexity isn't needed for current usage; that would also have the
problem that it might not be accurate after a local daylight savings
boundary.

(If it weren't for DST, we could simply replace this entire function
with "-timezone"; timezone contains the offset of the current timezone
(negated from what we want) but doesn't account for DST. And in spite
of being guaranteed by POSIX, it isn't available on older versions of
mingw.)

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-05-26 13:51:05 +03:00
Peter Krempa
81271a9261 storage: Add storage file API to read file headers
Add storage driver based functions to access headers of storage files
for metadata extraction. Along with this patch a local filesystem and
gluster via libgfapi implementation is provided. The gluster
implementation is based on code of the saferead_lim function.
2014-05-23 10:57:33 +02:00
Peter Krempa
ae26731e1f storage: Add support for access to files using provided uid/gid
To allow using the storage driver APIs to access files on various
storage sources in a universal fashion possibly on storage such as nfs
with root squash we'll need to store the desired uid/gid in the
metadata.

Add new initialisation API that will store the desired uid/gid and a
wrapper for the current use. Additionally add docs for the two APIs.
2014-05-23 10:48:48 +02:00