Before starting to go over the format string, prepare the current time
zone information incase '%z' or '%Z' is encountered.
This information can be obtained as given below:
A) If timezone is not set ( meaning we are working with system timezone):
Get the MYSQL_TIME representation for current time and GMT time using
current thread variable for timezone and timezone variable for UTC
respectively. This MYSQL_TIME variable will be used to calculate time
difference. Also convert current time in second to tm structure to
get system timezone information.
B) If timezone is set as offset:
Get timezone information using current timezone information and store
in appropriate variable.
C) If timezone is set as some place (example: Europe/Berlin)
Get timezone information by searching the timezone. During internal
timezone search, information like timeoffset from UTC and abbrevation
is stored in another relevant structure. Hence use the same information.
In particular:
* @@debug
deprecated since 5.5.37
* sr_YU locale
deprecated since 10.0.11
* "engine_condition_pushdown" in the @@optimizer_switch
deprecated since 10.1.1
* @@date_format, @@datetime_format, @@time_format, @@max_tmp_tables
deprecated since 10.1.2
* @@wsrep_causal_reads
deprecated since 10.1.3
* "parser" in mroonga table comment
deprecated since 10.2.11
Tests with checking metadata or that cannot be run with
the view-protocol are excluded from --view-protocol.
For tests that do not allow the use of an additional connection,
the util connection is disabled with "--disable_service_connection".
Also cases with bugs for --view-protocol are disabled.