The diagnostics_json call could access the std::unordered_map at the same
time it was being updated by the monitoring thread. This leads to
undefined behavior which in the case of MXS-3059 manifested as a segfault.
The mon_ping_or_connect_to_db resets the MYSQL handle which caused the
loss of the error message. Returning a new enumeration value for
authentication errors solves this problem.
The password values are now masked with asterisks. This tells whether a
password is set or not but it does not expose any information about the
password itself.
Galeramon will now only use the larger cluster in case a split brain
situation occurs. If the clusters are of equal size, the one whose UUID
compares less will be used. This will guarantee that all MaxScales that
see the same picture will end up using the same cluster.
name_lookup() now returns all results given by getnameinfo(). When searching
for a server, finding one matching address in the lookup-results is enough for
a match.
Also, added a test for name_lookup(). The test is minimal on its own, as hardcoded
test cases are not generally valid.
When matching hostnames between MaxScale server configuration and the
SHOW SLAVE STATUS-output, use DNS-resolution if a simple string comparison
doesn't find an answer. Results of the resolution are saved to avoid
repeating the operation for the same address.
The settings are different from the other fields in that they should not change
on their own. Most manipulation functions only require the settings.
Also takes into use a class for host and port data.
The first node without a priority would be chosen as the candidate master
and the rest would be ignored. The code must check if neither of the two
nodes have priorities and if so must choose the better one.
If code that may remove items from m_nodes_by_id (Clustrix nodes
keyed by id) succeeds, we must update the vector of health check
URLs also in the case that code that _may_ add items to m_nodes_by_id
fails.
