A core use case of the hook scripts is to be able to do things
to a guest's network configuration. It is possible to hook into
the 'start' operation for a QEMU guest which runs just before
the guest is started. The TAP devices will exist at this point,
but the QEMU process will not. It can be desirable to have a
'started' hook too, which runs once QEMU has started.
If libvirtd is restarted it will re-populate firewall rules,
but there is no QEMU hook to trigger for existing domains.
This is solved with a 'reconnect' hook.
Finally, if attaching to an external QEMU process there needs
to be an 'attach' hook script.
This all also applies to the LXC driver
* docs/hooks.html.in: Document new operations
* src/util/hooks.c, src/util/hooks.c: Add 'started', 'reconnect'
and 'attach' operations for QEMU. Add 'prepare', 'started',
'release' and 'reconnect' operations for LXC
* src/lxc/lxc_driver.c: Add hooks for 'prepare', 'started',
'release' and 'reconnect' operations
* src/qemu/qemu_process.c: Add hooks for 'started', 'reconnect'
and 'reconnect' operations
Return statements with parameter enclosed in parentheses were modified
and parentheses were removed. The whole change was scripted, here is how:
List of files was obtained using this command:
git grep -l -e '\<return\s*([^()]*\(([^()]*)[^()]*\)*)\s*;' | \
grep -e '\.[ch]$' -e '\.py$'
Found files were modified with this command:
sed -i -e \
's_^\(.*\<return\)\s*(\(\([^()]*([^()]*)[^()]*\)*\))\s*\(;.*$\)_\1 \2\4_' \
-e 's_^\(.*\<return\)\s*(\([^()]*\))\s*\(;.*$\)_\1 \2\3_'
Then checked for nonsense.
The whole command looks like this:
git grep -l -e '\<return\s*([^()]*\(([^()]*)[^()]*\)*)\s*;' | \
grep -e '\.[ch]$' -e '\.py$' | xargs sed -i -e \
's_^\(.*\<return\)\s*(\(\([^()]*([^()]*)[^()]*\)*\))\s*\(;.*$\)_\1 \2\4_' \
-e 's_^\(.*\<return\)\s*(\([^()]*\))\s*\(;.*$\)_\1 \2\3_'
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
We support to initialize the hooks at daemon reload if there is no
hooks script is defined, we should also support initialize the hooks
at daemon shutdown if no hooks is defined.
To address bz: https://bugzilla.redhat.com/show_bug.cgi?id=688859
This simplifies several callers that were repeating checks already
guaranteed by util.c, and makes other callers more robust to now
reject directories. remote_driver.c was over-strict - access(,R_OK)
is only needed to execute a script file; a binary only needs
access(,X_OK) (besides, it's unusual to see a file with x but not
r permissions, whether script or binary).
* cfg.mk (sc_prohibit_access_xok): New syntax-check rule.
(exclude_file_name_regexp--sc_prohibit_access_xok): Exempt one use.
* src/network/bridge_driver.c (networkStartRadvd): Fix offenders.
* src/qemu/qemu_capabilities.c (qemuCapsProbeMachineTypes)
(qemuCapsInitGuest, qemuCapsInit, qemuCapsExtractVersionInfo):
Likewise.
* src/remote/remote_driver.c (remoteFindDaemonPath): Likewise.
* src/uml/uml_driver.c (umlStartVMDaemon): Likewise.
* src/util/hooks.c (virHookCheck): Likewise.
Fix for bug https://bugzilla.redhat.com/show_bug.cgi?id=618970
The "prepare" hook is called very early in the VM statup process
before device labeling, so that it can allocate ressources not
managed by libvirt, such as DRBD, or for instance create missing
bridges and vlan interfaces.
* src/util/hooks.c src/util/hooks.h: add definitions for new hooks
VIR_HOOK_QEMU_OP_PREPARE and VIR_HOOK_QEMU_OP_RELEASE
* src/qemu/qemu_process.c: use them in qemuProcessStart and
qemuProcessStop()
This proof of concept shows how two existing uses of virExec
and virRun can be ported to the new virCommand APIs, and how
much simpler the code becomes
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.
The network filter / snapshot / hooks code introduced some
non-portable pices that broke the win32 build
* configure.ac: Check for net/ethernet.h required by nwfile config
parsing code
* src/conf/nwfilter_conf.c: Define ethernet protocol constants
if net/ethernet.h is missing
* src/util/hooks.c: Disable hooks build on Win32 since it lacks
fork/exec/pipe
* src/util/threads-win32.c: Fix unchecked return value
* tools/virsh.c: Disable SIGPIPE on Win32 since it doesn't exist.
Fix non-portable strftime() formats
This exports 3 basic routines:
- virHookInitialize() initializing the hook support by looking for
scripts availability
- virHookPresent() used to test if there is a hook for a given driver
- virHookCall() which actually calls a synchronous script hook with
the needed parameters
Note that this doesn't expose any public API except for the locations
and arguments passed to the scripts
* src/Makefile.am: add the 2 new files
* src/util/hooks.h src/util/hooks.c: implements the 3 functions
* src/libvirt_private.syms: export the 3 symbols internally
* po/POTFILES.in: add src/util/hooks.c to translatables modules
