* Fix clang warnings
* Remove vim tab guides
* initialize variables
* 'strncpy' output truncated before terminating nul copying as many bytes from a string as its length
* Fix ISO C++17 does not allow 'register' storage class specifier for outdated bison
* chars are unsigned on ARM, having if (ival < 0) always false
* chars are unsigned by default on ARM and comparison with -1 if always true
If an error occurs in mysql_real_query() it fell through and tried to
get a result set anyway. This caused the MariaDB error message to be
forgotten and a generic one returned instead.
This fix returns the query error message and also uses the int error
code for generic errors instead of casting it to an unsigned int.
