Commit Graph

61 Commits

Author SHA1 Message Date
Srivatsa S. Bhat
e352b16400 Export KVM Host Power Management capabilities
This patch exports KVM Host Power Management capabilities as XML so that
higher-level systems management software can make use of these features
available in the host.

The script "pm-is-supported" (from pm-utils package) is run to discover if
Suspend-to-RAM (S3) or Suspend-to-Disk (S4) is supported by the host.
If either of them are supported, then a new tag "<power_management>" is
introduced in the XML under the <host> tag.

However in case the query to check for power management features succeeded,
but the host does not support any such feature, then the XML will contain
an empty <power_management/> tag. In the event that the PM query itself
failed, the XML will not contain any "power_management" tag.

To use this, new APIs could be implemented in libvirt to exploit power
management features such as S3/S4.
2011-11-22 11:31:22 +08:00
Eric Blake
a218c81da2 API: add VIR_TYPED_PARAM_STRING
This allows strings to be transported between client and server
in the context of name-type-value virTypedParameter functions.
For compatibility,

    o new clients will not send strings to old servers, based on
      a feature check
    o new servers will not send strings to old clients without the
      flag VIR_TYPED_PARAM_STRING_OKAY; this will be enforced at
      the RPC layer in the next patch, so that drivers need not
      worry about it in general.  The one exception is that
      virDomainGetSchedulerParameters lacks a flags argument, so
      it must not return a string; drivers that forward that
      function on to virDomainGetSchedulerParametersFlags will
      have to pay attention to the flag.
    o the flag VIR_TYPED_PARAM_STRING_OKAY is set automatically,
      based on a feature check (so far, no driver implements it),
      so clients do not have to worry about it

Future patches can then enable the feature on a per-driver basis.

This patch also ensures that drivers can blindly strdup() field
names (previously, a malicious client could stuff 80 non-NUL bytes
into field and cause a read overrun).

* src/libvirt_internal.h (VIR_DRV_FEATURE_TYPED_PARAM_STRING): New
driver feature.
* src/libvirt.c (virTypedParameterValidateSet)
(virTypedParameterSanitizeGet): New helper functions.
(virDomainSetMemoryParameters, virDomainSetBlkioParameters)
(virDomainSetSchedulerParameters)
(virDomainSetSchedulerParametersFlags)
(virDomainGetMemoryParameters, virDomainGetBlkioParameters)
(virDomainGetSchedulerParameters)
(virDomainGetSchedulerParametersFlags, virDomainBlockStatsFlags):
Use them.
* src/util/util.h (virTypedParameterArrayClear): New helper
function.
* src/util/util.c (virTypedParameterArrayClear): Implement it.
* src/libvirt_private.syms (util.h): Export it.
Based on an initial patch by Hu Tao, with feedback from
Daniel P. Berrange.

Signed-off-by: Eric Blake <eblake@redhat.com>
2011-11-11 17:21:36 -07:00
Eric Blake
f7bd00c12c build: fix build on platforms without ptsname_r
MacOS lacks ptsname_r, and gnulib doesn't (yet) provide it.
But we can avoid it altogether, by using gnulib openpty()
instead.  Note that we do _not_ want the pt_chown module;
gnulib uses it only to implement a replacement openpty() if
the system lacks both openpty() and granpt(), but all
systems that we currently port to either have at least one of
openpty() and/or grantpt(), or lack ptys altogether.  That is,
we aren't porting to any system that requires us to deal with
the hassle of installing a setuid pt_chown helper just to use
gnulib's ability to provide openpty() on obscure platforms.

* .gnulib: Update to latest, for openpty fixes
* bootstrap.conf (gnulib_modules): Add openpty, ttyname_r.
(gnulib_tool_option_extras): Exclude pt_chown module.
* src/util/util.c (virFileOpenTty): Rewrite in terms of openpty
and ttyname_r.
* src/util/util.h (virFileOpenTtyAt): Delete dead prototype.
2011-11-07 09:34:02 -07:00
Michal Privoznik
458b7099b2 util: Create virFileAccessibleAs function
This function checks if a given path is accessible under
given uid and gid.
2011-10-25 09:27:02 +02:00
Peter Krempa
79cf07af7c Avoid using "devname" as an identifier.
/usr/lib/stdlib.h in Mac OS X and probably also in BSD's
exports this symbol :(
2011-09-16 20:49:04 +08:00
Eric Blake
71a0beaf3a build: simplify use of verify
Back in 2008 when this line of util.h was written, gnulib's verify
module didn't allow the use of multiple verify() in one file
in combination with our choice of gcc -W options.  But that has
since been fixed in gnulib, and newer gnulib even maps verify()
to the C1x feature of _Static_assert, which gives even nicer
diagnostics with a new enough compiler, so we might as well go
with the simpler verify().

* src/util/util.h (VIR_ENUM_IMPL): Use simpler verify, now that
gnulib module is smarter.
2011-08-30 09:23:20 -06:00
Stefan Berger
57c7b40b76 maint: fix some compilation issues on non-linux platforms (part 2)
Get rid of the #if __linux__ check in virPidFileReadPathIfAlive that
was preventing a check of a symbolic link in /proc/<pid>/exe on
non-linux platforms against an expected executable. Replace
this with a run-time check testing whether the /proc/<pid>/exe is a
symbolic link and if so call the function doing the comparison
against the expected file the link is supposed to point to.
2011-08-16 15:36:22 -04:00
Daniel P. Berrange
f80a4ed77a Move pidfile functions into util/virpidfile.{c,h}
The functions for manipulating pidfiles are in util/util.{c,h}.
We will shortly be adding some further pidfile related functions.
To avoid further growing util.c, this moves the pidfile related
functions into a dedicated virpidfile.{c,h}. The functions are
also all renamed to have 'virPidFile' as their name prefix

* util/util.h, util/util.c: Remove all pidfile code
* util/virpidfile.c, util/virpidfile.h: Add new APIs for pidfile
  handling.
* lxc/lxc_controller.c, lxc/lxc_driver.c, network/bridge_driver.c,
  qemu/qemu_process.c: Add virpidfile.h include and adapt for API
  renames
2011-08-12 20:37:00 +01:00
Laine Stump
6fe5fde292 util: define MAX
If util.h is going to have a MIN, it may as well also have MAX.
2011-07-21 14:45:20 -04:00
Daniel P. Berrange
accfe952eb Keep pidfile path in qemuDomainObjPrivate struct
Avoid re-formatting the pidfile path everytime we need it. Create
it once when starting the guest, and preserve it until the guest
is shutdown.

* src/libvirt_private.syms, src/util/util.c,
  src/util/util.h: Add virFileReadPidPath
* src/qemu/qemu_domain.h: Add pidfile field
* src/qemu/qemu_process.c: Store pidfile path in qemuDomainObjPrivate
2011-07-12 15:39:03 +01:00
Eric Blake
17da0669e0 util: drop unused safezero argument
No caller was using the flags argument, and this function is internal
only, so we might as well skip it.

* src/util/util.h (safezero): Update signature.
* src/util/util.c (safezero): Update function.
* src/locking/lock_driver_sanlock.c
(virLockManagerSanlockSetupLockspace)
(virLockManagerSanlockCreateLease): Update all callers.
* src/storage/storage_backend.c (createRawFile): Likewise.
2011-07-07 14:15:38 -06:00
Eric Blake
01374ec8b1 util: add virTrimSpaces
The next patch wants to adjust an end pointer to trim trailing
spaces but without modifying the underlying string, but a more
generally useful ability to trim trailing spaces in place is
also worth providing.

* src/util/util.h (virTrimSpaces, virSkipSpacesBackwards): New
prototypes.
* src/util/util.c (virTrimSpaces, virSkipSpacesBackwards): New
functions.
* src/libvirt_private.syms (util.h): Export new functions.
Inspired by a patch by Minoru Usui.
2011-07-06 15:17:14 -06:00
Eric Blake
82162316b6 util: fix virSkipSpaces
Most clients of virSkipSpaces don't want to omit backslashes.
Also, open-coding the list of spaces is not as nice as using
c_isspace.

* src/util/util.c (virSkipSpaces): Use c_isspace.
(virSkipSpacesAndBackslash): New function.
* src/util/util.h (virSkipSpacesAndBackslash): New prototype.
* src/xen/xend_internal.c (sexpr_to_xend_topology): Update caller.
* src/libvirt_private.syms (util.h): Export new function.
2011-07-06 14:52:43 -06:00
Eric Blake
8ce1afff88 util: choose whether to require micro in version strings
To avoid regressions, we let callers specify whether to require a
minor and micro version.  Callers that were parsing uname() output
benefit from defaulting to 0, whereas callers that were parsing
version strings from other sources should not change in behavior.

* src/util/util.c (virParseVersionString): Allow caller to choose
whether to fail if minor or micro is missing.
* src/util/util.h (virParseVersionString): Update signature.
* src/esx/esx_driver.c (esxGetVersion): Update callers.
* src/lxc/lxc_driver.c (lxcVersion): Likewise.
* src/openvz/openvz_conf.c (openvzExtractVersionInfo): Likewise.
* src/uml/uml_driver.c (umlGetVersion): Likewise.
* src/vbox/vbox_MSCOMGlue.c (vboxLookupVersionInRegistry):
Likewise.
* src/vbox/vbox_tmpl.c (vboxExtractVersion): Likewise.
* src/vmware/vmware_conf.c (vmwareExtractVersion): Likewise.
* src/xenapi/xenapi_driver.c (xenapiGetVersion): Likewise.
Reported by Matthias Bolte.
2011-07-01 11:22:11 -06:00
Jiri Denemark
ef6e99dc24 Introduce virTimeMs for getting current time in ms 2011-06-13 11:20:16 +02:00
Cole Robinson
02e86910e2 Move virRun, virExec*, virFork to util/command
Seems reasonable to have all command wrappers in the same place

v2:
    Dont move SetInherit

v3:
    Comment spelling fix
    Adjust WARN0 comment
    Remove spurious #include movement
    Don't include sys/types.h
    Combine virExec enums

Signed-off-by: Cole Robinson <crobinso@redhat.com>
2011-06-07 14:06:11 -04:00
Cole Robinson
d886ed9597 util: Remove unused virExec wrapper
v3:
    Remove obsolete comment

Signed-off-by: Cole Robinson <crobinso@redhat.com>
2011-06-07 11:12:58 -04:00
Richard Laager
4996c314b0 Fix virExecWithHook Prototype
This was necessary to get libvirt to build on Solaris 11 Express and
seems correct (as it makes this match the definition in util.c):
2011-05-29 10:09:00 +02:00
Cole Robinson
1ccc16c603 storage_backend: Convert virRunWithHook usage to virCommand
virRunWithHook is now unused, so we can drop it. Tested w/ raw + qcow2
volume creation and copying.

v2:
    Use opaque data to skip hook second time around
    Simply command building

v3:
    Drop explicit FindFileInPath
2011-05-17 10:16:38 -04:00
Cole Robinson
0f5599cd2a remote_driver: Convert virExecDaemonize usage to virCommand
And drop the now unused virExecDaemonize
2011-05-13 14:19:08 -04:00
Michal Privoznik
5d09c31495 Add warning message to XML definition files stored on disk
Users often edit XML file stored in configuration directory
thinking of modifying a domain/network/pool/etc. Thus it is wise
to let them know they are using the wrong way and give them hint.
2011-05-06 16:48:52 +02:00
Matthias Bolte
1573158190 Remove PATH_MAX sized stack allocations related to virFileBuildPath
Make virFileBuildPath operate on the heap instead of the stack. It
allocates a buffer instead of expecting a preexisting buffer.
2011-04-05 08:55:27 +02:00
Eric Blake
1fdd50f999 util: rename virFileOperation to virFileOpenAs
This patch intentionally doesn't change indentation, in order to
make it easier to review the real changes.

* src/util/util.h (VIR_FILE_OP_RETURN_FD, virFileOperationHook):
Delete.
(virFileOperation): Rename...
(virFileOpenAs): ...and reduce parameters.
* src/util/util.c (virFileOperationNoFork, virFileOperation):
Rename and simplify.
* src/qemu/qemu_driver.c (qemudDomainSaveFlag): Adjust caller.
* src/storage/storage_backend.c (virStorageBackendCreateRaw):
Likewise.
* src/libvirt_private.syms: Reflect rename.
2011-03-28 10:26:33 -06:00
Eric Blake
055d4ff87c util: use SCM_RIGHTS in virFileOperation when needed
Currently, the hook function in virFileOperation is extremely limited:
it must be async-signal-safe, and cannot modify any memory in the
parent process.  It is much handier to return a valid fd and operate
on it in the parent than to deal with hook restrictions.

* src/util/util.h (VIR_FILE_OP_RETURN_FD): New flag.
* src/util/util.c (virFileOperationNoFork, virFileOperation):
Honor new flag.
2011-03-28 10:26:33 -06:00
Eric Blake
296eb0bbe3 util: allow clearing cloexec bit
* src/util/util.h (virSetInherit): New prototype.
* src/util/util.c (virSetCloseExec): Move guts...
(virSetInherit): ...to new function, and allow clearing.
* src/libvirt_private.syms (util.h): Export it.
2011-03-28 10:26:32 -06:00
Daniel P. Berrange
bd82db4057 Add compat function for geteuid()
* configure.ac: Check for geteuid()
* src/util/util.h: Compat for geteuid()
2011-03-15 15:26:35 +00:00
Daniel P. Berrange
2737b6c20b Add virSetBlocking() to allow O_NONBLOCK to be toggle on or off
The virSetNonBlock() API only allows enabling non-blocking
operations. It doesn't allow turning blocking back on. Add
a new API to allow arbitrary toggling.

* src/libvirt_private.syms, src/util/util.h
  src/util/util.c: Add virSetBlocking
2011-03-15 15:26:35 +00:00
Daniel P. Berrange
35416720c2 Put <stdbool.h> into internal.h so it is available everywhere
Remove the <stdbool.h> header from all source files / headers
and just put it into internal.h

* src/internal.h: Add <stdbool.h>
2011-02-24 12:04:06 +00:00
Osier Yang
df1011ca8e storage: Allow to delete device mapper disk partition
The name convention of device mapper disk is different, and 'parted'
can't be used to delete a device mapper disk partition. e.g.

Name                 Path
-----------------------------------------
3600a0b80005ad1d7000093604cae912fp1 /dev/mapper/3600a0b80005ad1d7000093604cae912fp1

Error: Expecting a partition number.

This patch introduces 'dmsetup' to fix it.

Changes:
  - New function "virIsDevMapperDevice" in "src/utils/utils.c"
  - remove "is_dm_device" in "src/storage/parthelper.c", use
    "virIsDevMapperDevice" instead.
  - Requires "device-mapper" for 'with-storage-disk" in "libvirt.spec.in"
  - Check "dmsetup" in 'configure.ac' for "with-storage-disk"
  - Changes on "src/Makefile.am" to link against libdevmapper
  - New entry for "virIsDevMapperDevice" in "src/libvirt_private.syms"

Changes from v1 to v3:
  - s/virIsDeviceMapperDevice/virIsDevMapperDevice/g
  - replace "virRun" with "virCommand"
  - sort the list of util functions in "libvirt_private.syms"
  - ATTRIBUTE_NONNULL(1) for virIsDevMapperDevice declaration.

e.g.

Name                 Path
-----------------------------------------
3600a0b80005ad1d7000093604cae912fp1 /dev/mapper/3600a0b80005ad1d7000093604cae912fp1

Vol /dev/mapper/3600a0b80005ad1d7000093604cae912fp1 deleted

Name                 Path
-----------------------------------------
2011-02-17 15:29:07 +08:00
Eric Blake
1ff03b28e9 util: add missing string->integer conversion functions
It was awkward having only int conversion in the virStrToLong family,
but only long conversion in the virXPath family.  Make both families
support both types.

* src/util/util.h (virStrToLong_l, virStrToLong_ul): New
prototypes.
* src/util/xml.h (virXPathInt, virXPathUInt): Likewise.
* src/util/util.c (virStrToLong_l, virStrToLong_ul): New
functions.
* src/util/xml.c (virXPathInt, virXPathUInt): Likewise.
* src/libvirt_private.syms (util.h, xml.h): Export them.
2011-01-13 15:10:40 -07:00
Eric Blake
9ae992f243 virFindFileInPath: only find executable non-directory
Without this patch, at least tests/daemon-conf (which sticks
$builddir/src in the PATH) tries to execute the directory
$builddir/src/qemu rather than a real qemu binary.

* src/util/util.h (virFileExists): Adjust prototype.
(virFileIsExecutable): New prototype.
* src/util/util.c (virFindFileInPath): Reject non-executables and
directories.  Avoid huge stack allocation.
(virFileExists): Use lighter-weight syscall.
(virFileIsExecutable): New function.
* src/libvirt_private.syms (util.h): Export new function.
2011-01-13 08:10:55 -07:00
Laine Stump
d596c6dc9b new virSetUIDGID() utility function
virSetUIDGID() sets both the real and effective group and user of the
process, and additionally calls initgroups() to assure that the
process joins all the auxiliary groups that the given uid is a member
of.
2010-12-23 16:48:26 -05:00
Jean-Baptiste Rouault
966a1bfe22 Create file in virFileWriteStr() if it doesn't exist
This patch adds a mode_t parameter to virFileWriteStr().
If mode is different from 0, virFileWriteStr() will try
to create the file if it doesn't exist.

* src/util/util.h (virFileWriteStr): Alter signature.
* src/util/util.c (virFileWriteStr): Allow file creation.
* src/network/bridge_driver.c (networkEnableIpForwarding)
(networkDisableIPV6): Adjust clients.
* src/node_device/node_device_driver.c
(nodeDeviceVportCreateDelete): Likewise.
* src/util/cgroup.c (virCgroupSetValueStr): Likewise.
* src/util/pci.c (pciBindDeviceToStub, pciUnBindDeviceFromStub):
Likewise.
2010-12-03 08:08:22 -07:00
Eric Blake
fce3baee26 util: add virVasprintf
* src/util/util.h (virVasprintf): New declaration.
* src/util/util.c (virVasprintf): New function.
(virAsprintf): Use it.
* src/util/virtaudit.c (virAuditSend): Likewise.
* src/libvirt_private.syms: Export it.
* cfg.mk (sc_prohibit_asprintf): Also prohibit vasprintf.
* .x-sc_prohibit_asprintf: Add exemption.
2010-12-02 11:23:15 -07:00
Eric Blake
dbab6bb5cf util: fix saferead type
* src/util/util.c (saferead): Fix return type.
(safewrite): Fix indentation.
2010-12-02 11:23:15 -07:00
Osier Yang
af3ba2cd50 util: Add helper function to build timestamp string
* src/util/util.h
* src/util/util.c
* src/libvirt_private.syms
2010-11-01 17:05:11 -06:00
Matthias Bolte
1fe2927a34 Move hextobin as virHexToBin to util.c
virHexToBin will be used in the .vmx handling code.
2010-08-30 22:21:54 +02:00
Chris Lalancette
0117b7da68 Fix failing virGetHostname.
We've been running into a lot of situations where
virGetHostname() is returning "localhost", where a plain
gethostname() would have returned the correct thing.  This
is because virGetHostname() is *always* trying to canonicalize
the name returned from gethostname(), even when it doesn't
have to.

This patch changes virGetHostname so that if the value returned
from gethostname() is already FQDN or localhost, it returns
that string directly.  If the value returned from gethostname()
is a shortened hostname, then we try to canonicalize it.  If
that succeeds, we returned the canonicalized hostname.  If
that fails, and/or returns "localhost", then we just return
the original string we got from gethostname() and hope for
the best.

Note that after this patch it is up to clients to check whether
"localhost" is an allowed return value.  The only place
where it's currently not is in qemu migration.

Signed-off-by: Chris Lalancette <clalance@redhat.com>
2010-05-26 08:59:31 -04:00
Cole Robinson
a7fb2258ca storage: Sanitize pool target paths
Spurious / in a pool target path makes life difficult for apps using the
GetVolByPath, and doing other path based comparisons with pools. This
has caused a few issues for virt-manager users:

https://bugzilla.redhat.com/show_bug.cgi?id=494005
https://bugzilla.redhat.com/show_bug.cgi?id=593565

Add a new util API which removes spurious /, virFileSanitizePath. Sanitize
target paths when parsing pool XML, and for paths passed to GetVolByPath.

v2: Leading // must be preserved, properly sanitize path=/, sanitize
    away /./ -> /

v3: Properly handle starting ./ and ending /.

v4: Drop all '.' handling, just sanitize / for now.
2010-05-25 12:30:44 -04:00
Jiri Denemark
60aef9e467 Move MIN macro to util.h so that others can use it 2010-04-22 10:20:32 +02:00
Eric Blake
f9f6c34c5c util: ensure safe{read,write,zero} return is checked
Based on a warning from coverity.  The safe* functions
guarantee complete transactions on success, but don't guarantee
freedom from failure.

* src/util/util.h (saferead, safewrite, safezero): Add
ATTRIBUTE_RETURN_CHECK.
* src/remote/remote_driver.c (remoteIO, remoteIOEventLoop): Ignore
some failures.
(remoteIOReadBuffer): Adjust error messages on read failure.
* daemon/event.c (virEventHandleWakeup): Ignore read failure.
2010-04-15 11:40:08 -06:00
Matthias Bolte
56bac4a221 Refactor major.minor.micro version parsing into a function
virParseVersionString uses virStrToLong_ui instead of sscanf.

This also fixes a bug in the UML driver, that always returned 0
as version number.

Introduce STRSKIP to check if a string has a certain prefix and
to skip this prefix.
2010-04-01 12:53:41 +02:00
Daniel Veillard
b3bff9546b Export virPipeReadUntilEOF internally
used to read the data from virExec stdout/err file descriptors

* src/util/util.c src/util/util.h: not static anymore and export it
* src/libvirt_private.syms: allow access internally
2010-03-29 18:19:23 +02:00
Matthias Bolte
0f7ba8c21c util: Make some conditional symbols unconditional
Add dummy bodies for HAVE_GETPWUID_R and HAVE_MNTENT_H dependent
functions for MinGW builds.
2010-03-23 02:09:29 +01:00
Eric Blake
36d8e7d8d7 build: consistently indent preprocessor directives
* global: patch created by running:
for f in $(git ls-files '*.[ch]') ; do
    cppi $f > $f.t && mv $f.t $f
done
2010-03-09 19:22:28 +01:00
Laine Stump
fbadc2b608 Rename virFileCreate to virFileOperation, add hook function
It turns out it is also useful to be able to perform other operations
on a file created while running as a different uid (eg, write things
to that file), and possibly to do this to a file that already
exists. This patch adds an optional hook function to the renamed (for
more accuracy of purpose) virFileOperation; the hook will be called
after the file has been opened (possibly created) and gid/mode
checked/set, before closing it.

As with the other operations on the file, if the VIR_FILE_OP_AS_UID
flag is set, this hook function will be called in the context of a
child process forked from the process that called virFileOperation.
The implication here is that, while all data in memory is available to
this hook function, any modification to that data will not be seen by
the caller - the only indication in memory of what happened in the
hook will be the return value (which the hook should set to 0 on
success, or one of the standard errno values on failure).

Another piece of making the function more flexible was to add an
"openflags" argument. This arg should contain exactly the flags to be
passed to open(2), eg O_RDWR | O_EXCL, etc.

In the process of adding the hook to virFileOperation, I also realized
that the bits to fix up file owner/group/mode settings after creation
were being done in the parent process, which could fail, so I moved
them to the child process where they should be.

* src/util/util.[ch]: rename and rework virFileCreate-->virFileOperation,
  and redo flags in virDirCreate
* storage/storage_backend.c, storage/storage_backend_fs.c: update the
  calls to virFileOperation/virDirCreate to reflect changes in the API,
  but don't yet take advantage of the hook.
2010-02-19 17:43:22 +01:00
Chris Lalancette
b97c24b2e1 Better error reporting for failed migration
If the hostname as returned by "gethostname" resolves
to "localhost" (as it does with the broken Fedora-12
installer), then live migration will fail because the
source will try to migrate to itself.  Detect this
situation up-front and abort the live migration before
we do any real work.

* src/util/util.h src/util/util.c: add a new virGetHostnameLocalhost
  with an optional localhost check, and rewire virGetHostname() to use
  it
* src/libvirt_private.syms: expose the new function
* src/qemu/qemu_driver.c: use it in qemudDomainMigratePrepare2()
2010-02-19 16:15:21 +01:00
Laine Stump
b4584612b4 Add virFork() function to utils
virFork() contains bookkeeping that must be done any time a process
forks. Currently this includes:

1) Call virLogLock() prior to fork() and virLogUnlock() just after,
   to avoid a deadlock if some other thread happens to hold that lock
   during the fork.

2) Reset the logging hooks and send all child process log messages to
   stderr.

3) Block all signals prior to fork(), then either a) reset the signal
   mask for the parent process, or b) clear the signal mask for the
   child process.

Note that the signal mask handling in __virExec erroneously fails to
restore the signal mask when fork() fails. virFork() fixes this
problem.

Other than this, it attempts to behave as closely to fork() as
possible (including preserving errno for the caller), with a couple
exceptions:

1) The return value is 0 (success) or -1 (failure), while the pid is
   returned via the pid_t* argument. Like fork(), if pid < 0 there is
   no child process, otherwise both the child and the parent will
   return to the caller, and both should look at the return value,
   which will indicate if some of the extra processing outlined above
   encountered an error.

2) If virFork() returns with pid < 0 or with a return value < 0
   indicating an error condition, the error has already been
   reported. You can log an additional message if you like, but it
   isn't necessary, and may be awkwardly extraneous.

Note that virFork()'s child process will *never* call _exit() - if a
child process is created, it will return to the caller.

* util.c util.h: add virFork() function, based on what is currently
                 done in __virExec().
2010-02-18 22:13:48 +01:00
Jim Meyering
658952a38a virAsprintf: remove its warn_unused_result attribute
* src/util/util.h (virAsprintf): Remove ATTRIBUTE_RETURN_CHECK, since
it is perfectly fine to ignore the return value, now that the pointer
is guaranteed to be set to NULL upon failure.
* src/util/storage_file.c (absolutePathFromBaseFile): Remove now-
unnecessary use of ignore_value.
2010-02-10 12:30:13 +01:00
Matthias Bolte
f972dc2d5c Remove conn parameter from util functions
It was used for error reporting only.
2010-02-09 01:04:54 +01:00