When MaxScale starts it opens log file of each type and if there exist log files of same types in the same directory, it will try to reuse the file with largest sequence number in it. If there are no existing files, a file name with sequence number 1 will be created. If the file with largest sequence number is not writable, a new log file with larger sequence number will be created.
void session_enable_log(SESSION* ses, logfile_id_t id)
and
void session_disable_log(SESSION* ses, logfile_id_t id)
Which switch specific log type on/off if the log type in question is not generally enabled.
Each thread carries a thread-specific struct log_info_t which includes members for current session id and bitfield for enabled log types for the current session. That information is checked before actual log write functions are called.
Each file where session-specific logging is used, must include the following exports:
/** Defined in log_manager.cc */
extern int lm_enabled_logfiles_bitmask;
extern size_t log_ses_count[];
extern __thread log_info_t tls_log_info;
log_manager.cc:
Log manager handles cases where there are mismatch in user privileges.
Mark log files enabled in the global lm_enabled_logfiles_bitmask after initialization so that it reflects reality in error cases. In general, take into account the possibility that any phase in initialization may fail and read return values.
Replaced file_exists_and_is_writable to check_file_and_path which has a slightly different logic and which detects if file open fails for a few different reasons.
Improved logging (in stderr) in general in error cases.
gateway.c: Also check home directory accessibility in case when it is provided as a command-line argument. Added function check_dir_access to provide that function. Read return value of skysql_logmanager_init and exit (nicely) if it failed.
skygw_utils.cc: initialize mlist with version number 2, which indicates that object is initialized (different than zero) and that there are no active updates on the object (version%2==0).
Client flags are now copied to each backend and used in their connections.
log_manager.cc: fixed string allocation where one byte was missing.
mysql_client.c: fixed string allocation where one byte was missing.
log_manager.cc: fixed block buffer overflow. Queries are logged to trace log and long queries exceed the bufsize in length. Those were written beyond allocated memory areas.
mysql_client_server_protocol.h: added mysql_protocol_state_t to indicate whether MySQL protocol object is allocated, usable or freed. Freed means that memory allocations made by the protocol are freed. That is, command history etc.
mysql_backend.c: gw_backend_hangup and gw_error_backend_event used to call error handling function although session was already closing. Added check for session state.
mysql_client.c: route_by_statement lost some packets in case where query was sent in multiple packets.
mysql_common.c: gw_MySQL_get_next_packet failed in packet handling with route_by_statement. When multi-packet query was merged into one, packet type wasn't copied.
protocol_archive_srv_command and mysql_protocol_done didn't have proper locking in place which lead to occasional crashes.
query_classifier.cc use of uninitialized value in skygw_stmt_causes_implicit_commit
config.c crashed if module load failed, use of unitialized value
load_utils.c pretty-printed error
service.c use of uninitialized value in service_add_qualified_param
modules.h function prototype
readwritesplit.c memory leaks
