It's possible that cs->filename or cs->format could be read
in the 'fast' path while the 'slow' path is still constructing
the object. So we need to lock arr_next_lock before copying them
out for the caller.
Also wthread_should_exit was unprotected.
* log: Add high-resolution timestamp option for log files
This adds the %T option to the log format for millisecond timestamps. There's a feature test macro QB_FEATURE_LOG_HIRES_TIMESTAMPS so that applications know that they are available.
Because this changes the internal logging API, applications that use custom loggers will also need to change their custom logging destinations to take a struct timespec instead of a time_t. The above feature test macro will help in deciding which is appropriate.
As this patch also brought up some locking issues with re-configuring the logging while threaded logging was enabled, it also includes locking around qb_log_ctl2() and conversion of in_logger to an atomic.
This fixes issue with would-fail-if-applied-to-thread-right-away
qb_log_thread_priority_set invocation when logging thread doesn't
exist yet, which will arrange for calling itself at the time of
thread's birth that is the moment it will actually fail.
In this + lock-could-not-have-been-initialized corner cases, the
already running thread would proceed as allowed by error condition
handling in the main thread, trying to dereference uninitialized
(or outdated) pointer to the lock at hand, resulting in segfault.
Also include the test that would have been caught that (we use the
fact that it doesn't matter whether setting of the scheduler parameters
fails due to bad input or just because of lack of privileges as it's
the failure at the right moment that is of our interest).
See also:
https://github.com/ClusterLabs/libqb/issues/229
* configure.ac: Define QB_GNU.
Add a check for a working clock_getres for the CLOCK_MONOTONIC
option defining HAVE_CLOCK_GETRES_MONOTONIC.
* lib/log_thread.c: Replace second argument of
qb_log_thread_priority_set(): logt_sched_param.sched_priority by 0
when not supported by the OS.
* lib/util.c: Use the CLOCK_REALTIME option in clock_getres() if
HAVE_CLOCK_GETRES_MONOTONIC os not defined.
1) use gettimeofday() - suprisingly faster than clock_gettime(MONOTONIC)
2) don't format the time until it is needed
3) insert time_t into the blackbox (not a formatted string)
This improves performance and tidies the code up.
It also requires less space in the blackbox.
Signed-off-by: Angus Salkeld <asalkeld@redhat.com>
