Commit Graph

649 Commits

Author SHA1 Message Date
Peter Krempa
c246b02586 link-state: util: Add equality comparison functions for structures
This patch adds functions to compare structures containing network
device configuration for equality. They serve for the purpose of
disallowing unsupported changes to live network devices.
2011-09-06 16:05:53 +08:00
Peter Krempa
9fd3bb7a88 XML: Improve XML parsing error messages
This patch modifies error handling function for the XML parser provided
by libxml2.

Originaly only a line number and error message were logged. With this
new error handler function, the user is provided with a more complex
description of the parsing error.

Context of the error is printed in libXML2 style and filename of the
file, that caused the error is printed. Example of an parse error:

13:41:36.262: 16032: error : catchXMLError:706 :
/etc/libvirt/qemu/rh_bad.xml:58: Opening and ending tag mismatch: name
line 2 and domain
</domain>
---------^

Context of the error gives the user hints that may help to quickly
locate a corrupt xml file.

fixes BZs:
----------
Bug 708735 - [RFE] Show column and line on XML parsing error
https://bugzilla.redhat.com/show_bug.cgi?id=708735

Bug 726771 - libvirt does not specify problem file if persistent xml is
invalid
https://bugzilla.redhat.com/show_bug.cgi?id=726771
2011-09-06 15:48:22 +08:00
Michal Privoznik
597fe3cee6 daemon: Create priority workers pool
This patch annotates APIs with low or high priority.
In low set MUST be all APIs which might eventually access monitor
(and thus block indefinitely). Other APIs may be marked as high
priority. However, some must be (e.g. domainDestroy).

For high priority calls (HPC), there are some high priority workers
(HPW) created in the pool. HPW can execute only HPC, although normal
worker can process any call regardless priority. Therefore, only those
APIs which are guaranteed to end in reasonable small amount of time
can be marked as HPC.

The size of this HPC pool is static, because HPC are expected to end
quickly, therefore jobs assigned to this pool will be served quickly.
It can be configured in libvirtd.conf via prio_workers variable.
Default is set to 5.

To mark API with low or high priority, append priority:{low|high} to
it's comment in src/remote/remote_protocol.x. This is similar to
autogen|skipgen. If not marked, the generator assumes low as default.
2011-09-05 18:14:08 +02:00
Osier Yang
27758859c7 storage: Add fs pool formatting
This patch adds the ability to make the filesystem for a filesystem
pool during a pool build.

The patch adds two new flags, no overwrite and overwrite, to control
when mkfs gets executed.  By default, the patch preserves the
current behavior, i.e., if no flags are specified, pool build on a
filesystem pool only makes the directory on which the filesystem
will be mounted.

If the no overwrite flag is specified, the target device is checked
to determine if a filesystem of the type specified in the pool is
present.  If a filesystem of that type is already present, mkfs is
not executed and the build call returns an error.  Otherwise, mkfs
is executed and any data present on the device is overwritten.

If the overwrite flag is specified, mkfs is always executed, and any
existing data on the target device is overwritten unconditionally.
2011-09-02 21:16:58 +08:00
Daniel P. Berrange
c32536e7da Don't leak memory if a cgroup is mounted multiple times
It is possible (expected/likely in Fedora 15) for a cgroup controller
to be mounted in multiple locations at the same time, due to bind
mounts. Currently we leak memory if this happens, because we overwrite
the previous 'mountPoint' string. Instead just accept the first match
we find.

* src/util/cgroup.c: Only accept first match for a cgroup
  controller mount
2011-08-31 17:51:09 +01:00
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
Matthias Bolte
4d6e6f4aa9 hyperv: Add driver skeleton 2011-08-26 17:52:55 +02:00
Michal Privoznik
6c7299d47d virterror: Fix error message for VIR_ERR_INVALID_ARG
When a detail message is presented, nobody expects prefix 'invalid
argument in' but something more general, like 'invalid argument:'.
2011-08-26 16:40:42 +02:00
Daniel P. Berrange
ce93f64b1e Fix keymap used to talk with QEMU
The QEMU 'sendkey' command expects keys to be encoded in the same
way as the RFB extended keycode set. Specifically it wants extended
keys to have the high bit of the first byte set, while the Linux
XT KBD driver codeset uses the low bit of the second byte. To deal
with this we introduce a new keymap 'RFB' and use that in the QEMU
driver

* include/libvirt/libvirt.h.in: Add VIR_KEYCODE_SET_RFB
* src/qemu/qemu_driver.c: Use RFB keycode set instead of XT KBD
* src/util/virkeycode-mapgen.py: Auto-generate the RFB keycode
  set from the XT KBD set
* src/util/virkeycode.c: Add RFB keycode entry to table. Add a
  verify check on cardinality of the codeOffset table
2011-08-26 14:18:57 +01:00
Laine Stump
b1643dc15c util: only fchown newly created files in virFileOpenAs
virFileOpenAs takes desired uid:gid as arguments, and not only uses
them for a fork/setuid/setgid when retrying failed open operations,
but additionally always forces the opened file to be owned by the
given uid:gid.

One example of the problems this causes is that, when restoring a
domain from a file that is owned by the qemu user, opening the file
chowns it to root. if dynamic_ownership=1 this is coincidentally
expected, but if dynamic_ownership=0, no existing file should ever
have its ownership changed.

This patch adds an extra check before calling fchown() - it only does
it if O_CREAT was passed to virFileOpenAs() in the openflags.
2011-08-24 15:32:00 -04:00
Eric Blake
3a52b864dd maint: fix comment typos
* src/qemu/qemu_driver.c (qemuDomainSaveInternal): Fix typo.
* src/conf/domain_event.c (virDomainEventDispatchMatchCallback):
Likewise.
* daemon/libvirtd.c (daemonRunStateInit): Likewise.
* src/lxc/lxc_container.c (lxcContainerChildMountSort): Likewise.
* src/util/virterror.c (virCopyError, virRaiseErrorFull): Likewise.
* src/xenxs/xen_sxpr.c (xenParseSxprSound): Likewise.
2011-08-23 11:31:28 -06:00
KAMEZAWA Hiroyuki
9f5afc732c send-key: fix scan keycode map
Now, bad key-code in send-key can cause segmentation fault in libvirt.
(example)
 % virsh send-key --codeset win32 12
   error: End of file while reading data: Input/output error

This is caused by overrun at scanning keycode array.

Fix it.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
2011-08-22 07:24:15 -06:00
Eric Blake
751304e367 xml: add another convenience function
Often, we want to use XPath functions on the just-parsed document;
fold this into the parser function for convenience.

* src/util/xml.h (virXMLParseHelper): Add argument.
(virXMLParseStrHelper, virXMLParseFileHelper): Delete.
(virXMLParseCtxt, virXMLParseStringCtxt, virXMLParseFileCtxt): New
macros.
* src/libvirt_private.syms (xml.h): Remove deleted functions.
* src/util/xml.c (virXMLParseHelper): Add argument.
(virXMLParseStrHelper, virXMLParseFileHelper): Delete.
2011-08-19 09:13:54 -06:00
Eric Blake
c811de8fb7 build: fix virpidfile on mingw
Regression introduced in commit b7e5ca4.

Mingw lacks kill(), but we were only using it for a sanity check;
so we can go with one less check.

Also, on OOM error, this function should outright fail rather than
claim that the pid file was successfully read.

* src/util/virpidfile.c (virPidFileReadPathIfAlive): Skip kill
call where unsupported, and report error on OOM.
2011-08-17 11:51:24 -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
Stefan Berger
f4765b691d maint: fix some compilation issues on non-linux platforms
This patch fixes *some* compilation issues on non-Linux platforms (cygwin).
2011-08-16 13:54:15 -04:00
Roopa Prabhu
5abbf7b958 macvtap: Fix getPhysfn to get the PF of a direct attach network interface
This patch renames getPhysfn to getPhysfnDev and adds code to get the
Physical function and Virtual Function index of the direct attach linkdev (if
the direct attach interface is a SRIOV VF). The idea is to send the port
profile message to a PF if the direct attach interface is a SRIOV VF.

Signed-off-by: Roopa Prabhu <roprabhu@cisco.com>
Signed-off-by: Christian Benvenuti <benve@cisco.com>
Signed-off-by: David Wang <dwang2@cisco.com>
2011-08-16 11:59:00 -04:00
Roopa Prabhu
cd5544d412 interface: Add functions to get sriov PF/VF relationship of a net interface
This patch adds the following functions to get PF/VF relationship of an SRIOV
network interface:
ifaceIsVirtualFunction: Function to check if a network interface is a SRIOV VF
ifaceGetVirtualFunctionIndex: Function to get VF index if a network interface is a SRIOV VF
ifaceGetPhysicalFunction: Function to get the PF net interface name of a SRIOV VF net interface

Signed-off-by: Roopa Prabhu <roprabhu@cisco.com>
Signed-off-by: Christian Benvenuti <benve@cisco.com>
Signed-off-by: David Wang <dwang2@cisco.com>
2011-08-16 11:59:00 -04:00
Roopa Prabhu
17d64cab16 pci: Add helper functions for sriov devices
This patch adds the following helper functions:
pciDeviceIsVirtualFunction: Function to check if a pci device is a sriov VF
pciGetVirtualFunctionIndex: Function to get the VF index of a sriov VF
pciDeviceNetName: Function to get the network device name of a pci device
pciConfigAddressCompare: Function to compare pci config addresses

Signed-off-by: Roopa Prabhu <roprabhu@cisco.com>
Signed-off-by: Christian Benvenuti <benve@cisco.com>
Signed-off-by: David Wang <dwang2@cisco.com>
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
2011-08-16 11:59:00 -04:00
Roopa Prabhu
03172265d3 pci: Move some pci sriov helper code out of node device driver to util/pci
This patch moves some of the sriov related pci code from node_device driver
to src/util/pci.[ch]. Some functions had to go thru name and argument list
change to accommodate the move.

Signed-off-by: Roopa Prabhu <roprabhu@cisco.com>
Signed-off-by: Christian Benvenuti <benve@cisco.com>
Signed-off-by: David Wang <dwang2@cisco.com>
2011-08-16 11:59:00 -04:00
Eric Blake
be427e8b0b build: fix recent build failures
With gcc 4.5.1:

util/virpidfile.c: In function 'virPidFileAcquirePath':
util/virpidfile.c:308:66: error: nested extern declaration of '_gl_verify_function2' [-Wnested-externs]

Then in tests/commandtest.c, the new virPidFile APIs need to be used.

* src/util/virpidfile.c (virPidFileAcquirePath): Move verify to
top level.
* tests/commandtest.c: Use new pid APIs.
2011-08-12 16:16:29 -06:00
Daniel P. Berrange
e1da464d88 Add some APIs which use locking for crashsafe pidfile handling
In daemons using pidfiles to protect against concurrent
execution there is a possibility that a crash may leave a stale
pidfile on disk, which then prevents later restart of the daemon.

To avoid this problem, introduce a pair of APIs which make
use of virFileLock to ensure crash-safe & race condition-safe
pidfile acquisition & releae

* src/libvirt_private.syms, src/util/virpidfile.c,
  src/util/virpidfile.h: Add virPidFileAcquire and virPidFileRelease
2011-08-12 20:37:00 +01:00
Daniel P. Berrange
b7e5ca48f8 Introduce functions for checking whether a pidfile is valid
In some cases the caller of virPidFileRead might like extra checks
to determine whether the pid just read is really the one they are
expecting. This adds virPidFileReadIfAlive which will check whether
the pid is still alive with kill(0, -1), and (on linux only) will
look at /proc/$PID/path

* libvirt_private.syms, util/virpidfile.c, util/virpidfile.h: Add
  virPidFileReadIfValid and virPidFileReadPathIfValid
* network/bridge_driver.c: Use new APIs to check PID validity
2011-08-12 20:37:00 +01:00
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
Daniel P. Berrange
e48427051d Add virFileLock and virFileUnlock APIs
Add some simple wrappers around the fcntl() discretionary file
locking capability.

* src/util/util.c, src/util/util.h, src/libvirt_private.syms: Add
  virFileLock and virFileUnlock APIs
2011-08-12 20:37:00 +01:00
Eric Blake
c86827a243 util: plug memory leak
Leak detected by Coverity; only possible on unlikely ptsname_r
failure.  Additionally, the man page for ptsname_r states that
failure is merely non-zero, not necessarily -1.

* src/util/util.c (virFileOpenTtyAt): Avoid leak on ptsname_r
failure.
2011-08-02 16:39:02 -06:00
Eric Blake
d69b79ab72 interface: drop dead code
Coverity detected that ifaceGetNthParent had already dereferenced
'nth' prior to the conditional; all callers already complied with
passing a non-NULL pointer so make this part of the contract.

* src/util/interface.h (ifaceGetNthParent): Add annotations.
* src/util/interface.c (ifaceGetNthParent): Drop useless null check.
2011-08-02 16:39:01 -06:00
Eric Blake
44ebb18ec2 build: silence coverity false positives
Coverity complained that 395 out of 409 virAsprintf calls are
checked, and therefore assumed that the remaining cases are bugs
waiting to happen.  But in each of these cases, a failed virAsprintf
will properly set the target string to NULL, and pass on that
failure to the caller, without wasting efforts to check the call.
Adding the ignore_value silences Coverity.

* src/conf/domain_audit.c (virDomainAuditGetRdev): Ignore
virAsprintf return value, when it behaves like we need.
* src/network/bridge_driver.c (networkDnsmasqLeaseFileNameDefault)
(networkRadvdConfigFileName, networkBridgeDummyNicName)
(networkRadvdPidfileBasename): Likewise.
* src/util/storage_file.c (absolutePathFromBaseFile): Likewise.
* src/openvz/openvz_driver.c (openvzGenerateContainerVethName):
Likewise.
* src/util/command.c (virCommandTranslateStatus): Likewise.
2011-08-02 16:39:01 -06:00
Osier Yang
ef765169dd utils: More useful error message for hook script failure
Commit 3709a386 ported hooks codes to new command execution API,
together with the useful error message removed. Though we can't
get "errbuf" from the new command execution API anymore, still
we can give a more useful error.

https://bugzilla.redhat.com/show_bug.cgi?id=726398
2011-07-29 22:40:47 +08:00
Michal Privoznik
fe957f0a6f bandwidth: Integrate bandwidth into portgroups
Every DomainNetDef has a bandwidth, as does every portgroup.
Whenever a DomainNetDef of type NETWORK is about to be used, a call is
made to networkAllocateActualDevice(). This function chooses the "best"
bandwidth object and places it in the DomainActualNetDef.
From that point on, whenever some code needs to use the bandwidth data
for the interface, it's retrieved with virDomainNetGetActualBandwidth(),
which will always return the "best" info as determined in the
previous step.
2011-07-27 10:26:25 +02:00
Laine Stump
d6354c1696 util: change virFile*Pid functions to return < 0 on failure
Although most functions in libvirt return 0 on success and < 0 on
failure, there are a few functions lingering around that return errno
(a positive value) on failure, and sometimes code calling those
functions incorrectly assumes the <0 standard. I noticed one of these
the other day when auditing networkStartDhcpDaemon after Guido Gunther
found a place where success was improperly returned on failure (that
patch has been acked and is pending a push). The problem was that it
expected the return value from virFileReadPid to be < 0 on failure,
but it was actually positive (it was also neglected to set the return
code in this case, similar to the bug found by Guido).

This all led to the fact that *all* of the virFile*Pid functions in
util.c are returning errno on failure. This patch remedies that
problem by changing them all to return -errno on failure, and makes
any necessary changes to callers of the functions. (In the meantime, I
also properly set the return code on failure of virFileReadPid in
networkStartDhcpDaemon).
2011-07-25 16:56:26 -04:00
Michal Privoznik
90074ecfa7 bandwidth: Implement functions to enable and disable QoS
These function executes 'tc' with appropriate arguments to set
desired QoS setting on interface or bridge during its creation.
2011-07-25 13:49:55 +08:00
Michal Privoznik
aaa98b08ff bandwidth: Create format functions 2011-07-25 13:49:44 +08:00
Michal Privoznik
e2ed67a8b6 bandwidth: Add parsing and free functions
These functions parse given XML node and return pointer to the
output. Unknown elements are silently ignored. Attributes must
be integer and must fit in unsigned long long.

Free function frees elements of virBandwidth structure.
2011-07-25 13:49:33 +08:00
Michal Privoznik
7373188219 bandwidth: Declare internal structures 2011-07-25 13:49:18 +08:00
Laine Stump
c5d1592e20 util: add an ifaceGetIPAddress to the interface utilities
This function uses ioctl(SIOCGIFADDR), which limits it to returning
the first IPv4 address of an interface, but that's what we want right
now (the place we're going to use the address only accepts one).
2011-07-25 13:48:37 +08:00
Matthias Bolte
1a80a4e0d4 build: Use $(PYTHON) instead of python for the keycode map generator
Also prepend $(AM_V_GEN) to the command line, mark virkeycode-mapgen.py
as executable and switch the shebang line from /bin/python to the
commonly use /usr/bin/python.
2011-07-22 16:16:33 +02:00
Laine Stump
f7e18208e1 util: make interface.c functions consistently return < 0 on error
All of the functions in util/interface.c were returning 0 on success,
but some returned -1 on error, and some returned a positive value
(usually the value of errno, but sometimes just 1). Libvirt's standard
is to return < 0 on error (in the case of functions that need to
return errno, -errno is returned.

This patch modifies all functions in interface.c to consistently
return < 0 on error, and makes changes to callers of those functions
where necessary.
2011-07-22 09:27:07 -04:00
Eric Blake
519a1c4379 save: add virFileDirectFd wrapper type
O_DIRECT has stringent requirements.  Rather than make lots of changes
at each site that wants to use O_DIRECT, it is easier to offload
the work through a helper process that mirrors the I/O between a
pipe and the actual direct fd, so that the other end of the pipe
no longer has to worry about constraints.

Plus, if the kernel ever gains better posix_fadvise support, then we
only have to touch a single file to let all callers benefit from a
more efficient way to avoid file system caching.

* src/util/virfile.h (virFileDirectFdFlag, virFileDirectFdNew)
(virFileDirectFdClose, virFileDirectFdFree): New prototypes.
* src/util/virdirect.c: Implement new wrapper object.
* src/libvirt_private.syms (virfile.h): Export new symbols.
* cfg.mk (useless_free_options): Add to list.
* po/POTFILES.in: Add new translations.
2011-07-21 16:24:08 -06:00
Eric Blake
12291656b1 save: let iohelper work on O_DIRECT fds
Required for a coming patch where iohelper will operate on O_DIRECT
fds.  There, the user-space memory must be aligned to file system
boundaries (at least 512, but using page-aligned works better, and
some file systems prefer 64k).  Made tougher by the fact that
VIR_ALLOC won't work on void *, but posix_memalign won't work on
char * and isn't available everywhere.

This patch makes some simplifying assumptions - namely, output
to an O_DIRECT fd will only be attempted on an empty seekable
file (hence, no need to worry about preserving existing data
on a partial block, and ftruncate will work to undo the effects
of having to round up the size of the last block written), and
input from an O_DIRECT fd will only be attempted on a complete
seekable file with the only possible short read at EOF.

* configure.ac (AC_CHECK_FUNCS_ONCE): Check for posix_memalign.
* src/util/iohelper.c (runIO): Use aligned memory, and handle
quirks of O_DIRECT on last write.
2011-07-21 16:24:08 -06:00
Eric Blake
1eb6647979 save: let iohelper handle inherited fd
Rather than making the iohelper subject to a race in reopening
the file, it is nicer to pass an already-open fd by inheritance.

The old synopsis form must continue to work - if someone updates
their libvirt package and installs a new libvirt_iohelper but
without restarting the old libvirtd daemon, then the daemon can
still make calls using the old syntax but the new iohelper.

* src/util/iohelper.c (runIO): Split code for open...
(prepare): ...to new function.
(usage): Update synopsis.
(main): Allow alternate calling form.
* src/fdstream.c (virFDStreamOpenFileInternal): Use alternate form.
2011-07-21 16:24:08 -06:00
Eric Blake
1700345708 error: add new error type for reflecting partial API support
VIR_ERR_INVALID_ARG implies that an argument cannot possibly
be correct, given the current state of the API.
VIR_ERR_CONFIG_UNSUPPORTED implies that a configuration is
wrong, but arguments aren't configuration.
VIR_ERR_NO_SUPPORT implies that a function is completely
unimplemented.

But in the case of a function that is partially implemented,
yet the full power of the API is not available for that
driver, none of the above messages make sense.  Hence a new
error message, implying that the argument is known to comply
with the current state of the API, and that while the driver
supports aspects of the function, it does not support that
particular use of the argument.

A good use case for this is a driver that supports
virDomainSaveFlags, but not the dxml argument of that API.

It might be feasible to also use this new error for all functions
that check flags, and which accept fewer flags than what is possible
in the public API.  But doing so would get complicated, since
neither libvirt.c nor the remote driver may do flag filtering,
and every other driver would have to do a two-part check, first
using virCheckFlags on all public flags (which gives
VIR_ERR_INVALID_ARG for an impossible flag), followed by a
particular mask check for VIR_ERR_ARGUMENT_UNSUPPORTED (for a
possible public flag but unsupported by this driver).

* include/libvirt/virterror.h (VIR_ERR_ARGUMENT_UNSUPPORTED): New
error.
* src/util/virterror.c (virErrorMsg): Give it a message.
Suggested by Daniel P. Berrange.
2011-07-21 16:04:56 -06:00
Laine Stump
524655eea2 conf: virDomainNetDef points to (rather than contains) virtPortProfile
The virtPortProfile in the domain interface struct is now a separately
allocated object *pointed to by* (rather than contained in) the main
virDomainNetDef object. This is done to make it easier to figure out
when a virtualPortProfile has/hasn't been specified in a particular
config.
2011-07-21 14:46:39 -04:00
Laine Stump
a3d95b550b conf: put virtPortProfile struct / functions in a common location
virtPortProfiles are currently only used in the domain XML, but will
soon also be used in the network XML. To prepare for that change, this
patch moves the structure definition into util/network.h and the parse
and format functions into util/network.c (I decided that this was a
better choice than macvtap.h/c for something that needed to always be
available on all platforms).
2011-07-21 14:46:33 -04:00
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
Eric Blake
8e22e08935 build: rename files.h to virfile.h
In preparation for a future patch adding new virFile APIs.

* src/util/files.h, src/util/files.c: Move...
* src/util/virfile.h, src/util/virfile.c: ...here, and rename
functions to virFile prefix.  Macro names are intentionally
left alone.
* *.c: All '#include "files.h"' uses changed.
* src/Makefile.am (UTIL_SOURCES): Reflect rename.
* cfg.mk (exclude_file_name_regexp--sc_prohibit_close): Likewise.
* src/libvirt_private.syms: Likewise.
* docs/hacking.html.in: Likewise.
* HACKING: Regenerate.
2011-07-21 10:34:51 -06:00
Eric Blake
5d804ffae4 command: avoid leaking fds across fork
Since libvirt is multi-threaded, we should use FD_CLOEXEC as much
as possible in the parent, and only relax fds to inherited after
forking, to avoid leaking an fd created in one thread to a fork
run in another thread.  This gets us closer to that ideal, by
making virCommand automatically clear FD_CLOEXEC on fds intended
for the child, as well as avoiding a window of time with non-cloexec
pipes created for capturing output.

* src/util/command.c (virExecWithHook): Use CLOEXEC in parent.  In
child, guarantee that all fds to pass to child are inheritable.
(getDevNull): Use CLOEXEC.
(prepareStdFd): New helper function.
(virCommandRun, virCommandRequireHandshake): Use pipe2.
* src/qemu/qemu_command.c (qemuBuildCommandLine): Simplify caller.
2011-07-21 10:34:51 -06:00
Eric Blake
4289114518 command: move all docs into .c file
We already have a precedent of function documentation in C files,
where it is closer to the implementation (witness libvirt.h vs.
libvirt.c); maintaining docs in both files risks docs going stale.

While I was at it, I used consistent doxygen style on all comments.

* src/util/command.h: Remove duplicate docs, and move unique
documentation...
* src/util/command.c: ...here.
Suggested by Matthias Bolte.
2011-07-21 10:34:51 -06:00
Eric Blake
979b784be2 error: preserve errno when saving last error
It is common to see the sequence:

virErrorPtr save_err = virSaveLastError();
// do cleanup
virSetError(save_err);
virFreeError(save_err);

on cleanup paths.  But for functions where it is desirable to
return the errno that caused failure, this sequence can clobber
that errno.  virFreeError was already safe; this makes the other
two functions in the sequence safe as well, assuming all goes
well (on OOM, errno will be clobbered, but then again, save_err
won't reflect the real error that happened, so you are no longer
preserving the real situation - that's life with OOM).

* src/util/virterror.c (virSaveLastError, virSetError): Preserve
errno.
2011-07-21 07:24:33 -06:00
Wen Congyang
fd7c172340 cgroup: Implement cpu.cfs_period_us and cpu.cfs_quota_us tuning API
This patch provides 4 APIs to get and set cpu.cfs_period_us and cpu.cfs_quota_us.
2011-07-21 17:11:12 +08:00