These VIR_XXXX0 APIs make us confused, use the non-0-suffix APIs instead.
How do these coversions works? The magic is using the gcc extension of ##.
When __VA_ARGS__ is empty, "##" will swallow the "," in "fmt," to
avoid compile error.
example: origin after CPP
high_level_api("%d", a_int) low_level_api("%d", a_int)
high_level_api("a string") low_level_api("a string")
About 400 conversions.
8 special conversions:
VIR_XXXX0("") -> VIR_XXXX("msg") (avoid empty format) 2 conversions
VIR_XXXX0(string_literal_with_%) -> VIR_XXXX(%->%%) 0 conversions
VIR_XXXX0(non_string_literal) -> VIR_XXXX("%s", non_string_literal)
(for security) 6 conversions
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
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.
Commit e0d014f237 made binary potentially allocated on the heap.
It was freed in the parent in the error path, but not in the success path
that doesn't goto the cleanup label.
Found by 'make -C tests valgrind'.
Even with -Wuninitialized (which is part of autobuild.sh
--enable-compile-warnings=error), gcc does NOT catch this
use of an uninitialized variable:
{
if (cond)
goto error;
int a = 1;
error:
printf("%d", a);
}
which prints 0 (supposing the stack started life wiped) if
cond was true. Clang will catch it, but we don't use clang
as often. Using gcc -Wjump-misses-init catches it, but also
gives false positives:
{
if (cond)
goto error;
int a = 1;
return a;
error:
return 0;
}
Here, a was never used in the scope of the error block, so
declaring it after goto is technically fine (and clang agrees).
However, given that our HACKING already documents a preference
to C89 decl-before-statement, the false positive warning is
enough of a prod to comply with HACKING.
[Personally, I'd _really_ rather use C99 decl-after-statement
to minimize scope, but until gcc can efficiently and reliably
catch scoping and uninitialized usage bugs, I'll settle with
the compromise of enforcing a coding standard that happens to
reject false positives if it can also detect real bugs.]
* acinclude.m4 (LIBVIRT_COMPILE_WARNINGS): Add -Wjump-misses-init.
* src/util/util.c (__virExec): Adjust offenders.
* src/conf/domain_conf.c (virDomainTimerDefParseXML): Likewise.
* src/remote/remote_driver.c (doRemoteOpen): Likewise.
* src/phyp/phyp_driver.c (phypGetLparNAME, phypGetLparProfile)
(phypGetVIOSFreeSCSIAdapter, phypVolumeGetKey)
(phypGetStoragePoolDevice)
(phypVolumeGetPhysicalVolumeByStoragePool)
(phypVolumeGetPath): Likewise.
* src/vbox/vbox_tmpl.c (vboxNetworkUndefineDestroy)
(vboxNetworkCreate, vboxNetworkDumpXML)
(vboxNetworkDefineCreateXML): Likewise.
* src/xenapi/xenapi_driver.c (getCapsObject)
(xenapiDomainDumpXML): Likewise.
* src/xenapi/xenapi_utils.c (createVMRecordFromXml): Likewise.
* src/security/security_selinux.c (SELinuxGenNewContext):
Likewise.
* src/qemu/qemu_command.c (qemuBuildCommandLine): Likewise.
* src/qemu/qemu_hotplug.c (qemuDomainChangeEjectableMedia):
Likewise.
* src/qemu/qemu_process.c (qemuProcessWaitForMonitor): Likewise.
* src/qemu/qemu_monitor_text.c (qemuMonitorTextGetPtyPaths):
Likewise.
* src/qemu/qemu_driver.c (qemudDomainShutdown)
(qemudDomainBlockStats, qemudDomainMemoryPeek): Likewise.
* src/storage/storage_backend_iscsi.c
(virStorageBackendCreateIfaceIQN): Likewise.
* src/node_device/node_device_udev.c (udevProcessPCI): Likewise.
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.
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.
Child processes don't always reach _exit(); if they die from a
signal, then any messages should still be accurate. Most users
either expect a 0 status (thankfully, if status==0, then
WIFEXITED(status) is true and WEXITSTATUS(status)==0 for all
known platforms) or were filtering on WIFEXITED before printing
a status, but a few were missing this check. Additionally,
nwfilter_ebiptables_driver was making an assumption that works
on Linux (where WEXITSTATUS shifts and WTERMSIG just masks)
but fails on other platforms (where WEXITSTATUS just masks and
WTERMSIG shifts).
* src/util/command.h (virCommandTranslateStatus): New helper.
* src/libvirt_private.syms (command.h): Export it.
* src/util/command.c (virCommandTranslateStatus): New function.
(virCommandWait): Use it to also diagnose status from signals.
* src/security/security_apparmor.c (load_profile): Likewise.
* src/storage/storage_backend.c
(virStorageBackendQEMUImgBackingFormat): Likewise.
* src/util/util.c (virExecDaemonize, virRunWithHook)
(virFileOperation, virDirCreate): Likewise.
* daemon/remote.c (remoteDispatchAuthPolkit): Likewise.
* src/nwfilter/nwfilter_ebiptables_driver.c (ebiptablesExecCLI):
Likewise.
If virFileIsExecutable is to replace access(file,X_OK), then
errno must be usable on failure.
* src/util/util.c (virFileIsExecutable): Set errno on failure.
virExec would only resolved the binary to $PATH if no env
variables were being set. Since there is no execvep() API
in POSIX, we use virFindFileInPath to manually resolve
the binary and then use execv() instead of execvp().
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
In virFileOperation, the parent does a fallback to a non-fork
attempt if it detects that the child returned EACCES. However,
the child was calling _exit(-EACCES), which does _not_ appear
as EACCES in the parent.
* src/util/util.c (virFileOperation): Correctly pass EACCES from
child to parent.
The virFileAbsPath was not taking into account the '/' directory
separator when allocating memory for combining cwd + path. Convert
to use virAsprintf to avoid this type of bug completely.
* src/util/util.c: Convert virFileAbsPath to use virAsprintf
Done mechanically with:
$ git grep -l '\bDEBUG0\? *(' | xargs -L1 sed -i 's/\bDEBUG0\? *(/VIR_&/'
followed by manual deletion of qemudDebug in daemon/libvirtd.c, along
with a single 'make syntax-check' fallout in the same file, and the
actual deletion in src/util/logging.h.
* src/util/logging.h (DEBUG, DEBUG0): Delete.
* daemon/libvirtd.h (qemudDebug): Likewise.
* global: Change remaining clients over to VIR_DEBUG counterpart.
Two regressions:
Commit df1011ca broke builds for systems that lack devmapper
(non-Linux, as well as Linux with ./autogen.sh --without-libvirtd
and without the libraries present).
Commit ce6fd650 broke cross-compilation, due to a gnulib bug.
* .gnulib: Update to latest, for cross-compilation fix.
* src/util/util.c (virIsDevMapperDevice): Provide stub for
platforms not using storage driver.
* configure.ac (devmapper): Arrange to define HAVE_LIBDEVMAPPER_H.
devmapper issue reported by Wen Congyang.
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
-----------------------------------------
Some functionality run in virExec hooks may do I/O which
can trigger SIGPIPE. Renable SIGPIPE blocking around the
hook function
* src/util/util.c: Block SIGPIPE around hooks
* src/fdstream.c (virFDStreamOpenFile, virFDStreamCreateFile):
Use VIR_FORCE_CLOSE instead of close.
* tests/commandtest.c (mymain): Likewise.
* tools/virsh.c (editFile): Use virCommand instead of system.
* src/util/util.c (__virExec): Special case preservation of std
file descriptors to child.
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.
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.
Detected on cygwin:
util/util.c: In function 'virSetUIDGID':
util/util.c:2824: warning: format '%d' expects type 'int', but argument 7 has type 'gid_t' [-Wformat]
(and three other lines)
* src/util/util.c (virSetUIDGID): Cast, as is done elsewhere in
this file, to avoid printf type mismatch warnings.
As pointed out in https://bugzilla.redhat.com/show_bug.cgi?id=659855#c9,
commit c3568ec2 introduced a regression where we no longer close any
fd's beyond FD_SETSIZE.
* src/util/util.c (__virExec): Continue to close fd's beyond
keepfd range.
Reported by Stefan Praszalowicz.
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.
Allows compilation, but no creation of child processes yet. Take it
one step at a time.
* src/util/util.c (virExecWithHook) [WIN32]: New dummy function.
* src/libvirt_private.syms: Export it.
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.
The QEMU logger appends a ':' to the timestamp when it deems
it neccessary, so the virTimestamp API should not duplicate
this
* src/util/util.c: Remove trailing ':' from timestamp
The virFork call resets all logging handlers that may have been
set. Re-enable them after fork in virExec, so that env variables
fir LIBVIRT_LOG_OUTPUTS and LIBVIRT_LOG_FILTERS take effect
until the execve()
* src/util/util.c: Preserve logging in child in virExec
Similarly to deprecating close(), I am now deprecating fclose() and
introduce VIR_FORCE_FCLOSE() and VIR_FCLOSE(). Also, fdopen() is replaced with
VIR_FDOPEN().
Most of the files are opened in read-only mode, so usage of
VIR_FORCE_CLOSE() seemed appropriate. Others that are opened in write
mode already had the fclose()< 0 check and I converted those to
VIR_FCLOSE()< 0.
I did not find occurrences of possible double-closed files on the way.
Using automated replacement with sed and editing I have now replaced all
occurrences of close() with VIR_(FORCE_)CLOSE() except for one, of
course. Some replacements were straight forward, others I needed to pay
attention. I hope I payed attention in all the right places... Please
have a look. This should have at least solved one more double-close
error.
virPipeReadUntilEOF is used to read the stdout of exec'ed
and this could fail to capture the full output and read only
1024 bytes.
The problem is that this is based on a poll loop, and in the
loop we read at most 1024 bytes per file descriptor, but we also
note in the loop if poll indicates that the process won't output
more than that on that fd by setting finished[i] = 1.
The simplest way is that if we read a full buffer make sure
finished[i] is still 0 because we will need another pass in the
loop.
Commit 9bd3cce0d2 added virFork and
virDriverLoadModule to libvirt_private.syms, but virFork didn't have
a body on Win32 and virDriverLoadModule was already correctly
exported conditional via libvirt_driver_modules.syms.
This patch fixes a couple of complaints from valgrind when tickling libvirtd with SIGHUP.
The first two files contain fixes for memory leaks. The 3rd one initializes an uninitialized variable. The 4th one is another memory leak.
virDiskNameToIndex has a list of disk name prefixes that it uses in the
process of finding the disk's index. This list is missing "ubd" which
is the disk prefix used for UML domains.
Signed-off-by: Soren Hansen <soren@linux2go.dk>
virDirCreate also previously returned 0 on success and errno on
failure. This makes it fit the recommended convention of returning 0
on success, -errno (ie a negative number) on failure.
virFileOperation previously returned 0 on success, or the value of
errno on failure. Although there are other functions in libvirt that
use this convention, the preferred (and more common) convention is to
return 0 on success and -errno (or simply -1 in some cases) on
failure. This way the check for failure is always (ret < 0).
* src/util/util.c - change virFileOperation and virFileOperationNoFork to
return -errno on failure.
* src/storage/storage_backend.c, src/qemu/qemu_driver.c
- change the hook functions passed to virFileOperation to return
-errno on failure.
Any error message raised after the process has forked needs
to be followed by virDispatchError, otherwise we have no chance of
ever seeing it. This was selectively done for hook functions in the past,
but really applies to all post-fork errors.
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>
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=494005https://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.
virFileResolveLink was returning a positive value on error,
thus confusing callers that assumed failure was < 0. The
confusion is further evidenced by callers that would have
ended up calling virReportSystemError with a negative value
instead of a valid errno.
Fixes Red Hat BZ #591363.
* src/util/util.c (virFileResolveLink): Live up to documentation.
* src/qemu/qemu_security_dac.c
(qemuSecurityDACRestoreSecurityFileLabel): Adjust callers.
* src/security/security_selinux.c
(SELinuxRestoreSecurityFileLabel): Likewise.
* src/storage/storage_backend_disk.c
(virStorageBackendDiskDeleteVol): Likewise.
Gnulib can guarantee that pthread.h exists, but for now, it is a dummy
header with no support for most pthread_* functions. Modify our
use of pthread to use function checks, rather than header checks,
to determine how much pthread support is present.
* bootstrap.conf (gnulib_modules): Add pthread.
* configure.ac: Drop all pthread.h checks. Optimize function
checks. Add check for pthread functions.
* src/Makefile.am (libvirt_lxc_LDADD): Ensure proper link.
* src/remote/remote_driver.c (remoteIOEventLoop): Depend on
pthread_sigmask, now that gnulib guarantees pthread.h.
* src/util/util.c (virFork): Likewise.
* src/util/threads.c (threads-pthread.c): Depend on
pthread_mutexattr_init, as a witness of full pthread support.
* src/util/threads.h (threads-pthread.h): Likewise.
Detected by clang. POSIX requires that the second argument to
va_start be the name of the last variable; and in some implementations,
passing *path instead of path would dereference bogus memory instead
of pulling arguments off the stack.
* src/util/util.c (virBuildPathInternal): Use correct argument to
va_start.
Add an empty body for virCondWaitUntil and move virPipeReadUntilEOF
out of the '#ifndef WIN32' block, because it compiles fine with MinGW
in combination with gnulib.
Necessary on cygwin, where uid_t and gid_t are 4-byte long rather
than int, causing gcc -Wformat warnings.
* src/util/util.c (virFileOperationNoFork, virDirCreateNoFork)
(virFileOperation, virDirCreate, virGetUserEnt): Cast uid_t and
gid_t before passing to printf.
* .gitignore: Ignore Windows executables.
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.
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
Even if gnulib can provide stubs, it won't help that much. So just
replace affected util functions (virFileOperation and virDirCreate)
with stubs on Windows. Both functions aren't used on libvirt's
client side, so this is fine for MinGW builds.
to saferead_lim, which interprets it as a size_t.
* src/util/util.c (virFileReadLimFD): Do not malfunction when
maxlen < -1. Return -1,EINVAL in that case. Handle maxlen==0
in the same manner.
Various safezero() implementations used either -1, errno or -errno
return values. This patch fixes them all to return -1 and set errno
appropriately.
There was also a bug in size parameter passed to safewrite() which could
result in an attempt to write gigabytes out of a megabyte buffer.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
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.
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()
For __virExec() this is a semantic NOP except for when fork()
fails. __virExec() would previously forget to restore the signal mask
in this case; virFork() corrects this behavior.
virFileCreate() and virDirCreate() gain the code to reset the logging
and properly deal with the signal handling race condition.
This also removes a log message that had a typo ("cannot fork o create
file '%s'") - this error is now logged in a more generic manner in
virFork() (more generic, but really just as informative, since the
fact that it's forking to create a file is immaterial to the fact that
it simply can't fork)
* src/util/util.c: use the generic virFork() in the 3 functions
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().
Similar fix as previous one but for fork() usage when creating
a file or directory
* src/util/util.c: virLogLock() and virLogUnlock() around fork()
in virFileCreate() and virDirCreateSimple()
Ad pointed out by Dan Berrange:
So if some thread in libvirtd is currently executing a logging call,
while another thread calls virExec(), that other thread no longer
exists in the child, but its lock is never released. So when the
child then does virLogReset() it deadlocks.
The only way I see to address this, is for the parent process to call
virLogLock(), immediately before fork(), and then virLogUnlock()
afterwards in both parent & child. This will ensure that no other
thread
can be holding the lock across fork().
* src/util/logging.[ch] src/libvirt_private.syms: export virLogLock() and
virLogUnlock()
* src/util/util.c: lock just before forking and unlock just after - in
both parent and child.
* src/util/util.c (virGetUserID, virGetGroupID): In the unlikely event
that sysconf(_SC_GETPW_R_SIZE_MAX) fails, don't use -1 as the size in
the subsequent allocation.
On RHEL-5 the qemu-kvm binary is located in /usr/libexec.
To reduce confusion for people trying to run upstream libvirt
on RHEL-5 machines, make the qemu driver look in /usr/libexec
for the qemu-kvm binary.
To make this work, I modified virFindFileInPath to handle an
absolute path correctly. I also ran into an issue where
NULL was sometimes being passed for the file parameter
to virFindFileInPath; it didn't crash prior to this patch
since it was building paths like /usr/bin/(null). This
is non-standard behavior, though, so I added a NULL
check at the beginning.
Signed-off-by: Chris Lalancette <clalance@redhat.com>
* src/util/util.c (virGetUserEnt): In the unlikely event that
sysconf(_SC_GETPW_R_SIZE_MAX) fails, don't use -1 as the size in
the subsequent allocation.
virFileMakePath is a recursive function that was creates a buffer
PATH_MAX bytes long for each recursion (one recursion for each element
in the path). This changes it to have no buffers on the stack, and to
allocate just one buffer total, no matter how many elements are in the
path. Because the modified algorithm requires a char* to be passed in
rather than const char *, it is now 2 functions - a toplevel API
function that remains identical in function, and a 2nd helper function
called for the recursions, which 1) doesn't allocate anything, and 2)
takes a char* arg, so it can modify the contents.
* src/util/util.c: rewrite virFileMakePath
These functions create a new file or directory with the given
uid/gid. If the flag VIR_FILE_CREATE_AS_UID is given, they do this by
forking a new process, calling setuid/setgid in the new process, and
then creating the file. This is better than simply calling open then
fchown, because in the latter case, a root-squashing nfs server would
create the new file as user nobody, then refuse to allow fchown.
If VIR_FILE_CREATE_AS_UID is not specified, the simpler tactic of
creating the file/dir, then chowning is is used. This gives better
results in cases where the parent directory isn't on a root-squashing
NFS server, but doesn't give permission for the specified uid/gid to
create files. (Note that if the fork/setuid method fails to create the
file due to access privileges, the parent process will make a second
attempt using this simpler method.)
If the bit VIR_FILE_CREATE_ALLOW_EXIST is set in the flags, an
existing file/directory will not cause an error; in this case, the
function will simply set the permissions of the file/directory to
those requested. If VIR_FILE_CREATE_ALLOW_EXIST is not specified, an
existing file/directory is considered (and reported as) an error.
Return from both of these functions is 0 on success, or the value of
errno if there was a failure.
* src/util/util.[ch]: add the 2 new util functions
