Class which manages slow and general log event handlers. More...

#include <log.h>

Public Member Functions
	Query_logger ()

bool	is_log_table_enabled (enum_log_table_type log_type) const
	Check if table logging is turned on for the given log_type. More...

bool	is_log_file_enabled (enum_log_table_type log_type) const
	Check if file logging is turned on for the given log type. More...

void	init ()
	Perform basic log initialization: create file-based log handler. More...

void	cleanup ()
	Free memory. More...

bool	slow_log_write (THD thd, const char query, size_t query_length, bool aggregate, ulonglong lock_usec, ulonglong exec_usec)
	Log slow query with all enabled log event handlers. More...

bool	general_log_print (THD thd, enum_server_command command, const char format,...)
	Write printf style message to general query log. More...

bool	general_log_write (THD thd, enum_server_command command, const char query, size_t query_length)
	Write query to general query log. More...

void	set_handlers (ulonglong log_printer)
	Enable log event handlers for slow/general log. More...

bool	activate_log_handler (THD *thd, enum_log_table_type log_type)
	Activate log handlers for the given log type. More...

void	deactivate_log_handler (enum_log_table_type log_type)
	Close file log for the given log type. More...

bool	reopen_log_file (enum_log_table_type log_type)
	Close file log for the given log type and the reopen it. More...

bool	set_log_file (enum_log_table_type log_type)
	Read log file name from global variable opt_*_logname. More...

enum_log_table_type	check_if_log_table (Table_ref *table_list, bool check_if_opened) const
	Check if given Table_ref has a query log table name and optionally check if the query log is currently enabled. More...

Private Member Functions
void	init_query_log (enum_log_table_type log_type, ulonglong log_printer)
	Setup log event handlers for the given log_type. More...

Private Attributes
mysql_rwlock_t	LOCK_logger
	RW-lock protecting Query_logger. More...

Log_to_csv_event_handler	table_log_handler
	Available log handlers. More...

Log_to_file_event_handler *	file_log_handler

Log_event_handler *	slow_log_handler_list [MAX_LOG_HANDLERS_NUM+1]
	NULL-terminated arrays of log handlers. More...

Log_event_handler *	general_log_handler_list [MAX_LOG_HANDLERS_NUM+1]

Static Private Attributes
static const uint	MAX_LOG_HANDLERS_NUM = 2
	Currently we have only 2 kinds of logging functions: old-fashioned file logs and csv logging routines. More...

Detailed Description

Class which manages slow and general log event handlers.

Constructor & Destructor Documentation

◆ Query_logger()

Query_logger::Query_logger ( )

inline

Member Function Documentation

◆ activate_log_handler()

bool Query_logger::activate_log_handler	(	THD *	thd,
		enum_log_table_type	log_type
	)

Activate log handlers for the given log type.

Parameters

thd	Thread handle
log_type	QUERY_LOG_SLOW or QUERY_LOG_GENERAL

Returns: true if error, false otherwise.

◆ check_if_log_table()

enum_log_table_type Query_logger::check_if_log_table	(	Table_ref *	table_list,
		bool	check_if_opened
	)		const

Check if given Table_ref has a query log table name and optionally check if the query log is currently enabled.

Parameters

table_list	Table_ref representing the table to check
check_if_opened	Always return QUERY_LOG_NONE unless the query log table is enabled.

Return values

QUERY_LOG_NONE,QUERY_LOG_SLOW or QUERY_LOG_GENERAL

◆ cleanup()

void Query_logger::cleanup ( )

Free memory.

Nothing could be logged after this function is called.

◆ deactivate_log_handler()

void Query_logger::deactivate_log_handler ( enum_log_table_type log_type )

Close file log for the given log type.

Parameters

log_type QUERY_LOG_SLOW or QUERY_LOG_GENERAL

◆ general_log_print()

bool Query_logger::general_log_print	(	THD *	thd,
		enum_server_command	command,
		const char *	format,
			...
	)

Write printf style message to general query log.

Parameters

thd	THD of the statement being logged.
command	COM of statement being logged.
format	Printf style format of message.
...	Printf parameters to write.

Returns: true if error, false otherwise.

◆ general_log_write()

bool Query_logger::general_log_write	(	THD *	thd,
		enum_server_command	command,
		const char *	query,
		size_t	query_length
	)

Write query to general query log.

Parameters

thd	THD of the statement being logged.
command	COM of statement being logged.
query	The query string being logged.
query_length	The length of the query string.

Returns: true if error, false otherwise.

◆ init()

void Query_logger::init ( )

Perform basic log initialization: create file-based log handler.

We want to initialize all log mutexes as soon as possible, but we cannot do it in constructor, as safe_mutex relies on initialization, performed by MY_INIT(). This why this is done in this function.

◆ init_query_log()

void Query_logger::init_query_log	(	enum_log_table_type	log_type,
		ulonglong	log_printer
	)

private

Setup log event handlers for the given log_type.

Parameters

log_type	QUERY_LOG_SLOW or QUERY_LOG_GENERAL
log_printer	Bitmap of LOG_NONE, LOG_FILE, LOG_TABLE

◆ is_log_file_enabled()

bool Query_logger::is_log_file_enabled ( enum_log_table_type log_type ) const

Check if file logging is turned on for the given log type.

Parameters

log_type QUERY_LOG_SLOW or QUERY_LOG_GENERAL

Returns: true if the file logging is on, false otherwise.

◆ is_log_table_enabled()

bool Query_logger::is_log_table_enabled ( enum_log_table_type log_type ) const

Check if table logging is turned on for the given log_type.

Parameters

log_type QUERY_LOG_SLOW or QUERY_LOG_GENERAL

Returns: true if table logging is on, false otherwise.

◆ reopen_log_file()

bool Query_logger::reopen_log_file ( enum_log_table_type log_type )

Close file log for the given log type and the reopen it.

Parameters

log_type QUERY_LOG_SLOW or QUERY_LOG_GENERAL

◆ set_handlers()

void Query_logger::set_handlers ( ulonglong log_printer )

Enable log event handlers for slow/general log.

Parameters

log_printer Bitmask of log event handlers.

Note: Acceptable values are LOG_NONE, LOG_FILE, LOG_TABLE

◆ set_log_file()

bool Query_logger::set_log_file ( enum_log_table_type log_type )

Read log file name from global variable opt_*_logname.

If called from a sys_var update function, the caller must hold a lock protecting the sys_var (LOCK_global_system_variables, a polylock for the variable, etc.).

Parameters

log_type QUERY_LOG_SLOW or QUERY_LOG_GENERAL

◆ slow_log_write()

bool Query_logger::slow_log_write	(	THD *	thd,
		const char *	query,
		size_t	query_length,
		bool	aggregate,
		ulonglong	lock_usec,
		ulonglong	exec_usec
	)

Log slow query with all enabled log event handlers.

Parameters

thd	THD of the statement being logged.
query	The query string being logged.
query_length	The length of the query string.
aggregate	True if writing log throttle record
lock_usec	Lock time, in microseconds. Only used when aggregate is true.
exec_usec	Execution time, in microseconds. Only used when aggregate is true.

Returns: true if error, false otherwise.

Member Data Documentation

◆ file_log_handler

Log_to_file_event_handler* Query_logger::file_log_handler

private

◆ general_log_handler_list

Log_event_handler* Query_logger::general_log_handler_list[MAX_LOG_HANDLERS_NUM+1]

private

◆ LOCK_logger

mysql_rwlock_t Query_logger::LOCK_logger

private

RW-lock protecting Query_logger.

R-lock taken when writing to slow/general query log. W-lock taken when activating/deactivating logs.

◆ MAX_LOG_HANDLERS_NUM

const uint Query_logger::MAX_LOG_HANDLERS_NUM = 2

staticprivate

Currently we have only 2 kinds of logging functions: old-fashioned file logs and csv logging routines.

◆ slow_log_handler_list

Log_event_handler* Query_logger::slow_log_handler_list[MAX_LOG_HANDLERS_NUM+1]

private

NULL-terminated arrays of log handlers.

◆ table_log_handler

Log_to_csv_event_handler Query_logger::table_log_handler

private

Available log handlers.

The documentation for this class was generated from the following files:

sql/log.h
sql/log.cc

Public Member Functions

Private Member Functions

Private Attributes

Static Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ Query_logger()

Member Function Documentation

◆ activate_log_handler()

◆ check_if_log_table()

◆ cleanup()

◆ deactivate_log_handler()

◆ general_log_print()

◆ general_log_write()

◆ init()

◆ init_query_log()

◆ is_log_file_enabled()

◆ is_log_table_enabled()

◆ reopen_log_file()

◆ set_handlers()

◆ set_log_file()

◆ slow_log_write()

Member Data Documentation

◆ file_log_handler

◆ general_log_handler_list

◆ LOCK_logger

◆ MAX_LOG_HANDLERS_NUM

◆ slow_log_handler_list

◆ table_log_handler