Previously, the parent process opened 'null' to /dev/null, then
the child process closes 'null' as well as 'childout'. But if
childout was set to be null, then this is a double close. At
least the double close was confined to the child process after a
fork, and therefore there is no risk of another thread opening
an fd of the same value to be bitten by the double close, but it
is always better to avoid double-close to begin with.
Additionally, if all three fds were specified, then opening
'null' was wasted.
This patch fixes things to lazily open null on the first use,
then guarantees it gets closed exactly once.
* src/util/command.c (getDevNull): New helper function.
(virExecWithHook): Use it to avoid spurious opens and double close.
This also reduces malloc pressure for invoking a child when
VIR_DEBUG is enabled.
* src/util/command.c (virExecWithHook): Drop debug, since the only
caller (virCommandRunAsync) also prints debug info.
The below patch decreases the response time of libvirt to errors reported by Qemu upon startup by checking whether the qemu process is still alive while polling for the local socket to show up.
This patch also introduces a special handling of signal for the Win32 part of virKillProcess.
Coverity already saw through a NULL dereference without these
annotations, and gcc is still too puny to do good NULL analysis.
But clang still benefits (and is easier to run than coverity),
not to mention that adding this bit of documentation to the code
may help future developers remember the constraints.
* src/util/uuid.h (virGetHostUUID, virUUIDFormat): Document
restrictions, for improved static analysis.
Similar in nature to commit fd21ecfd, which shut up valgrind.
sigaction is apparently a nasty interface for analyzer tools,
at least for how many false positives it generates.
* src/util/command.c (virExecWithHook): Initialize entire var, since
coverity gripes about the (unused and non-standard) sa_restorer.
Detected by Coverity. The code was doing math on shifted unsigned
char (which promotes to int), then promoting that to unsigned long
during assignment to size. On 64-bit platforms, this risks sign
extending values of size > 2GiB. Bug present since commit
489fd3 (v0.6.0).
I'm not sure if a specially-crafted bogus qcow2 image could
exploit this, although it's probably not possible, since we
were already checking for the computed results being within
range of our fixed-size buffer.
* src/util/storage_file.c (qcowXGetBackingStore): Avoid sign
extension.
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>
Coverity complained that infd could be -1 at the point where it is
passed to write, when in reality, this code can only be reached if
infd is non-negative.
* src/util/command.c (virCommandProcessIO): Help out coverity.
Spotted by coverity. Triggers on failed stat, although I'm not sure
how easy that condition is, so I'm not sure if this is a runtime
memory hog. Regression introduced in commit 8077d64 (unreleased).
* src/util/storage_file.c (virStorageFileGetMetadataFromFD):
Reduce need for malloc, avoiding a leak.
Detected by Coverity. While it is possible on OOM condition, as
well as with bad code that passes binary == NULL, it is unlikely
to be encountered in the wild.
* src/util/command.c (virCommandNewArgList): Don't leak memory.
Define the basic framework lock manager plugins. The
basic plugin API for 3rd parties to implemented is
defined in
src/locking/lock_driver.h
This allows dlopen()able modules for alternative locking
schemes, however, we do not install the header. This
requires lock plugins to be in-tree allowing changing of
the lock manager plugin API in future.
The libvirt code for loading & calling into plugins
is in
src/locking/lock_manager.{c,h}
* include/libvirt/virterror.h, src/util/virterror.c: Add
VIR_FROM_LOCKING
* src/locking/lock_driver.h: API for lock driver plugins
to implement
* src/locking/lock_manager.c, src/locking/lock_manager.h:
Internal API for managing locking
* src/Makefile.am: Add locking code
Allow the parent process to perform a bi-directional handshake
with the child process during fork/exec. The child process
will fork and do its initial setup. Immediately prior to the
exec(), it will stop & wait for a handshake from the parent
process. The parent process will spawn the child and wait
until the child reaches the handshake point. It will do
whatever extra setup work is required, before signalling the
child to continue.
The implementation of this is done using two pairs of blocking
pipes. The first pair is used to block the parent, until the
child writes a single byte. Then the second pair pair is used
to block the child, until the parent confirms with another
single byte.
* src/util/command.c, src/util/command.h,
src/libvirt_private.syms: Add APIs to perform a handshake
Substitute VIR_ERR_NO_SUPPORT with VIR_ERR_INTERNAL_ERROR. Error
like following is not what user want to see.
error : pciDeviceIsAssignable:1487 : this function is not supported
by the connection driver: Device 0000:07:10.0 is behind a switch
lacking ACS and cannot be assigned
Since directories can be used for <filesystem> passthrough, they are
basically storage volumes.
v2:
Skip ., .., lost+found dirs
v3:
Use gnulib last_component
v4:
Use gnulib "dirname.h", not system <dirname.h>
Don't skip lost+found
The virSysinfoIsEqual method was mistakenly inside a #ifndef WIN32
conditional.
The existing virSysinfoFormat is also stubbed out on Win32, even
though the code works without any trouble. This breaks XML output
on Win32, so the stub is removed.
virsh migrate mistakenly had some variables inside the conditional
* src/util/sysinfo.c: Build virSysinfoIsEqual on Win32 and remove
Win32 stub for virSysinfoFormat
* tools/virsh.c: Fix variable declaration on Win32
To allow a client app to pass in custom XML during migration
of a guest it is neccessary to ensure the guest ABI remains
unchanged. The virDomainDefCheckABIStablity method accepts
two virDomainDefPtr structs and compares everything in them
that could impact the guest machine ABI
* src/conf/domain_conf.c, src/conf/domain_conf.h,
src/libvirt_private.syms: Add virDomainDefCheckABIStablity
* src/conf/cpu_conf.c, src/conf/cpu_conf.h: Add virCPUDefIsEqual
* src/util/sysinfo.c, src/util/sysinfo.h: Add virSysinfoIsEqual
Coverity spotted this off-by-one. Thankfully, no one in libvirt
was ever calling virAuditSend with an argument of 3.
* src/util/virtaudit.c (virAuditSend): Use correct comparison.
We don't use the gnulib vsnprintf replacement, which means that
on mingw, vsnprintf doesn't support %zn or %lln.
And as it turns out, VIR_GET_VAR_STR was a rather inefficient
reimplementation of virVasprintf logic.
* src/util/logging.c (VIR_GET_VAR_STR): Drop.
(virLogMessage): Inline a simpler version here.
* src/util/virterror.c (VIR_GET_VAR_STR, virRaiseErrorFull):
Likewise.
Reported by Matthias Bolte.
Two additional places need initgroups call to properly work in an
environment where the UID is allowed to open/create stuff through its
supplementary groups.
This error code has existed since the dawn of time, yet the messages it
generates are almost universally busted. Here's a small sampling:
src/conf/domain_conf.c:4889 : XML description for missing root element is not well formed or invalid
src/conf/domain_conf.c:4951 : XML description for unknown device type is not well formed or invalid
src/conf/domain_conf.c:5460 : XML description for maximum vcpus must be an integer is not well formed or invalid
src/conf/domain_conf.c:5468 : XML description for invalid maxvcpus %(count)lu is not well formed or invalid
Fix up the error code to instead be
XML error: <msg>
Adjust the few locations that were using the original correctly (or shouldn't
have been using the error code at all).
v2:
Fix wording of error code without a passed argument
starting with kernel 2.6.38 macvtap supports a 'passthru' mode for
attaching virtual functions of a SRIOV capable network card directly to a VM.
This patch adds the capability to configure such a device.
Signed-off-by: Dirk Herrendoerfer <d.herrendoerfer@herrendoerfer.name>
POSIX allows sysconf(_SC_GETPW_R_SIZE_MAX) to return -1 if there
is no fixed limit, and requires ERANGE errors to track real size.
Model our behavior after the example in POSIX itself:
http://pubs.opengroup.org/onlinepubs/9699919799/functions/getpwuid_r.html
Also, on error for get*_r functions, errno is undefined, and the
real error was the return value.
* src/util/util.c (virGetUserEnt, virGetUserID, virGetGroupID)
(virSetUIDGID): Cope with sysconf failure or too small buffer.
Reported by Matthias Bolte.
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
Mingw execve() has a broken signature. Disable this
function until gnulib fixes the signature, since we
don't really need this on Win32 anyway.
* src/util/command.c: Disable virCommandExec on Win32
This is needed if we want to transfer a temporary file. If the
transfer is done with iohelper, we might run into a race condition,
where we unlink() file before iohelper is executed.
* src/fdstream.c, src/fdstream.h,
src/util/iohelper.c: Add new option
* src/lxc/lxc_driver.c, src/qemu/qemu_driver.c,
src/storage/storage_driver.c, src/uml/uml_driver.c,
src/xen/xen_driver.c: Expand existing function calls
We were 31/73 on whether to translate; since less than 50% translated
and since VIR_INFO is less than VIR_WARN which also doesn't translate,
this makes sense.
* cfg.mk (sc_prohibit_gettext_markup): Add VIR_INFO, since it
falls between WARN and DEBUG.
* daemon/libvirtd.c (qemudDispatchSignalEvent, remoteCheckAccess)
(qemudDispatchServer): Adjust offenders.
* daemon/remote.c (remoteDispatchAuthPolkit): Likewise.
* src/network/bridge_driver.c (networkReloadIptablesRules)
(networkStartNetworkDaemon, networkShutdownNetworkDaemon)
(networkCreate, networkDefine, networkUndefine): Likewise.
* src/qemu/qemu_driver.c (qemudDomainDefine)
(qemudDomainUndefine): Likewise.
* src/storage/storage_driver.c (storagePoolCreate)
(storagePoolDefine, storagePoolUndefine, storagePoolStart)
(storagePoolDestroy, storagePoolDelete, storageVolumeCreateXML)
(storageVolumeCreateXMLFrom, storageVolumeDelete): Likewise.
* src/util/bridge.c (brProbeVnetHdr): Likewise.
* po/POTFILES.in: Drop src/util/bridge.c.
Use of ',##__VA_ARGS__' is a gcc extension not guaranteed by
C99; thankfully, we can avoid it by lumping the format argument
into the var-args set.
* src/util/logging.h (VIR_DEBUG_INT, VIR_INFO_INT, VIR_WARN_INT)
(VIR_ERROR_INT, VIR_DEBUG, VIR_INFO, VIR_WARN, VIR_ERROR): Stick
to C99 var-arg macro syntax.
* examples/domain-events/events-c/event-test.c (VIR_DEBUG):
Simplify.
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>
Version 2.0.0 or yajl changed API. It is fairly trivial for us to
cope with both APIs in libvirt, so adapt.
* configure.ac: Probe for yajl2 API
* src/util/json.c: Conditional support for yajl2 API
Actually execs the argv/env we've generated, replacing the current process.
Kind of has a limited usage, but allows us to use virCommand in LXC
driver to launch the 'init' process
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.
Match the fact that we have virAsprintf and virVasprintf.
* src/util/buf.h (virBufferVasprintf): New prototype.
* src/util/buf.c (virBufferAsprintf): Move guts...
(virBufferVasprintf): ...to new function.
* src/libvirt_private.syms (buf.h): Export it.
* bootstrap.conf (gnulib_modules): Add stdarg, for va_copy.
We already have virAsprintf, so picking a similar name helps for
seeing a similar purpose. Furthermore, the prefix V before printf
generally implies 'va_list', even though this variant was '...', and
the old name got in the way of adding a new va_list version.
global rename performed with:
$ git grep -l virBufferVSprintf \
| xargs -L1 sed -i 's/virBufferVSprintf/virBufferAsprintf/g'
then revert the changes in ChangeLog-old.
