... and update all users. No change in functionality, the parameter
will be used later.
The metadata representation is as minimal as possible, but requires
the caller to allocate an array on stack explicitly.
The alternative of using varargs in the virLogMessage() callers:
* Would not allow the caller to optionally omit some metadata elements,
except by having two calls to virLogMessage.
* Would not be as type-safe (e.g. using int vs. size_t), and the compiler
wouldn't be able to do type checking
* Depending on parameter order:
a) virLogMessage(..., message format, message params...,
metadata..., NULL)
can not be portably implemented (parse_printf_format() is a glibc
function)
b) virLogMessage(..., metadata..., NULL,
message format, message params...)
would prevent usage of ATTRIBUTE_FMT_PRINTF and the associated
compiler checking.
Signed-off-by: Miloslav Trmač <mitr@redhat.com>
Commit e8fd8757c8 changed 'const char *'
category to virLogSource enum. This changes it in virLogEatParams as
well, thus fixing the build with --disable-debug.
--
Hopefully moving the enum declarations is less ugly than using int.
Add support for logging to the systemd journal, using its
simple client library. The benefit over syslog is that it
accepts structured log data, so the journald can store
individual items like code file/line/func separately from
the string message. Tools which require structured log
data can then query the journal to extract exactly what
they desire without resorting to string parsing
While systemd provides a simple client library for logging,
it is more convenient for libvirt to directly write its
own client code. This lets us build up the iovec's on
the stack, avoiding the need to alloc memory when writing
log messages.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The 'const char *category' parameter only has a few possible
values now that the filename has been separated. Turn this
parameter into an enum instead.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Currently the logging APIs have a 'const char *category' parameter
which indicates where the log message comes from. This is typically
a combination of the __FILE__ string and other prefix. Split the
__FILE__ off into a dedicated parameter so it can passed to the
log outputs
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
General whitespace cleanup in the logging files
- Move '{' to a new line after funtion declaration
- Put each parameter on a new line to avoid long lines
- Put return type on new line
- Leave 2 blank lines between functions
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The log destinations are an enum, but most of the code was
just using a plain 'int' for function params / variables.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The __LINE__ macro value is specified to fit in the size_t
type, so use that instead of 'long long' in the logging code
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The log priority levels are an enum, but most of the code was
just using a plain 'int' for function params / variables.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
In addition to the preformatted text line, pass the raw message as well,
to allow the output functions to use a different output format.
Signed-off-by: Miloslav Trmač <mitr@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Nothing uses the return value, and creating it requries otherwise
unnecessary strlen () calls.
This cleanup is conceptually independent from the rest of the series
(although the later patches won't apply without it). This just seems
a good opportunity to clean this up, instead of entrenching the unnecessary
return value in the virLogOutputFunc instance that will be added in this
series.
Signed-off-by: Miloslav Trmač <mitr@redhat.com>
https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.
* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/; If/. If/
Remove the use of a manually run virLogStartup and
virNodeSuspendInitialize methods. Instead make sure they
are automatically run using VIR_ONCE_GLOBAL_INIT
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)
You should have received a copy of the GNU General Public License
along with Foobar. If not, see <http://www.gnu.org/licenses/>.
This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').
Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:
src/security/security_selinux.h
src/security/security_driver.h
src/security/security_selinux.c
src/security/security_apparmor.h
src/security/security_apparmor.c
src/security/security_driver.c
When building with --disable-debug, VIR_DEBUG expands to a nop.
But parameters to VIR_DEBUG can be variables that are passed only
to VIR_DEBUG. In the case the building system complains about unused
variables.
Allow the logging APIs to be called with a va_list for format
args, instead of requiring var-args usage.
* src/util/logging.h, src/util/logging.c: Add virLogVMessage
Sometimes it is useful to see the callpath for log messages.
This change enhances the log filter syntax so that stack traces
can be show by setting '1:+NAME' instead of '1:NAME'.
This results in output like:
2012-05-09 14:18:45.136+0000: 13314: debug : virInitialize:414 : register drivers
/home/berrange/src/virt/libvirt/src/.libs/libvirt.so.0(virInitialize+0xd6)[0x7f89188ebe86]
/home/berrange/src/virt/libvirt/tools/.libs/lt-virsh[0x431921]
/lib64/libc.so.6(__libc_start_main+0xf5)[0x3a21e21735]
/home/berrange/src/virt/libvirt/tools/.libs/lt-virsh[0x40a279]
2012-05-09 14:18:45.136+0000: 13314: debug : virRegisterDriver:775 : driver=0x7f8918d02760 name=Test
/home/berrange/src/virt/libvirt/src/.libs/libvirt.so.0(virRegisterDriver+0x6b)[0x7f89188ec717]
/home/berrange/src/virt/libvirt/src/.libs/libvirt.so.0(+0x11b3ad)[0x7f891891e3ad]
/home/berrange/src/virt/libvirt/src/.libs/libvirt.so.0(virInitialize+0xf3)[0x7f89188ebea3]
/home/berrange/src/virt/libvirt/tools/.libs/lt-virsh[0x431921]
/lib64/libc.so.6(__libc_start_main+0xf5)[0x3a21e21735]
/home/berrange/src/virt/libvirt/tools/.libs/lt-virsh[0x40a279]
* docs/logging.html.in: Document new syntax
* configure.ac: Check for execinfo.h
* src/util/logging.c, src/util/logging.h: Add support for
stack traces
* tests/testutils.c: Adapt to API change
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
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>
This is the part allowing to dynamically resize the debug log
buffer from it's default 64kB size. The buffer is now dynamically
allocated.
It adds a new API virLogSetBufferSize() which resizes the buffer
If passed a zero size, the buffer is deallocated and we do the small
optimization of not formatting messages which are not output anymore.
On the daemon side, it just adds a new option log_buffer_size to
libvirtd.conf and call virLogSetBufferSize() if needed
* src/util/logging.h src/util/logging.c src/libvirt_private.syms:
make buffer dynamic and add virLogSetBufferSize() internal API
* daemon/libvirtd.conf: document the new log_buffer_size option
* daemon/libvirtd.c: read and use the new log_buffer_size option
virLogEmergencyDumpAll() allows to dump the content of the
debug buffer from within a signal handler. It saves to all
log file or stderr if none is found
* src/util/logging.h src/util/logging.c: add the new API
and cleanup the old virLogDump code
* src/libvirt_private.syms: exports it as a private symbol
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.
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.
When configuring logging settings, keep more information about the
output destination. Add accessors to retrieve the filter and output
settings in the original string form; this to be used to set up
environment for a child process that also logs.
* src/util/logging.[ch]: add virLogGetFilters and virLogGetOutputs
accessors and modify the internals (including virLogDefineOutput())
to save the data needed for the accessors
