The master and slave bits were previously set in more then one place.
This spread out the handling of those status bits and now all replication
related bits are set in one place.
If galeramon isn't able to connect to a Galera node, the server state is left
unaltered. This will cause servers that lose connectivity to be in RUNNING|JOINED
state which causes them to be assigned with the SLAVE status. For servers that are
never accessible, the state will be RUNNING.
Since there is but one log file where error, warning, notice, info
and debug messages are written, calling it "error.log" is misleading.
Consequently the log file is renamed to "maxscale.log".
Switched to ExternalProject CMake module to make the inclusion of external CMake
projects easier. This removes the rebuilding of the pcre2 libraries each time
the project is reconfigured.
The soname version numbers were missing from all the library targets
properties which caused ldconfig to warn about non-symlink libraries
being installed.
Earlier, by default, the error and message logfiles were written to
the filesystem and trace and debug logfiles to shared memory. Now,
with just one log-file the default must be the file-system. However,
if info and debug messages are logged, then the filesystem will
become a bottle-neck.
A reasonable approach is then as follows (in the config file)
syslog=true
maxlog=false
log_to_shm=true
With this set, the maxlog file will be created to shared memory, but
nothing will be written to it, since it is disabled. However, if there
is a need to investigate something, then a dba can from maxadmin turn
on maxlog logging and also enable info and debug messages. That is, it
will be possible to enable debugging output without restarting maxscale.
Incidentally, the way the config file and command line arguments are
handled should be rewritten. Currently, it is a mess.
There were some variance regarding the way the MaxScale log (i.e.
the file log) was called; "maxlog" in configuration file and
"maxscalelog" at the command line and maxadmin interface. Now it
is uniformly referred to as "maxlog" in the configuration file, at
the command line, from maxadmin and in the code.
It should not be possible to disable the error priority as error
messages should always be logged.
In addition some minor corrections of command line texts.
