A sys_var that is an alias for another sys_var. More...

#include <sys_vars.h>

Inheritance diagram for Sys_var_alias:

Public Member Functions
	Sys_var_alias (const char *name_arg, sys_var &base_var)

sys_var &	get_base_var ()

void	cleanup () override
	All the cleanup procedures should be performed here. More...

sys_var_pluginvar *	cast_pluginvar () override
	downcast for sys_var_pluginvar. More...

void	update_default (longlong new_def_value) override

longlong	get_default () override

longlong	get_min_value () override

ulonglong	get_max_value () override

ulong	get_var_type () override
	Returns variable type. More...

void	set_arg_source (get_opt_arg_source *arg_source) override

void	set_is_plugin (bool is_plugin) override

bool	is_non_persistent () override

void	saved_value_to_string (THD thd, set_var var, char *def_val) override
	This function converts value stored in save_result to string. More...

bool	check_update_type (Item_result type) override

enum_variable_source	get_source () override

const char *	get_source_name () override

void	set_source (enum_variable_source src) override

bool	set_source_name (const char *path) override

bool	set_user (const char *usr) override

const char *	get_user () override

const char *	get_host () override

bool	set_host (const char *hst) override

ulonglong	get_timestamp () const override

void	set_user_host (THD *thd) override

void	set_timestamp () override

void	set_timestamp (ulonglong ts) override

Public Member Functions inherited from sys_var
	sys_var (sys_var_chain chain, const char name_arg, const char comment, int flag_args, ptrdiff_t off, int getopt_id, enum get_opt_arg_type getopt_arg_type, SHOW_TYPE show_val_type_arg, longlong def_val, PolyLock lock, enum binlog_status_enum binlog_status_arg, on_check_function on_check_func, on_update_function on_update_func, const char substitute, int parse_flag, sys_var persisted_alias=nullptr, bool is_persisted_deprecated=false)
	sys_var constructor More...

virtual	~sys_var ()=default

const char *	get_deprecation_substitute ()

bool	check (THD thd, set_var var)

const uchar *	value_ptr (THD running_thd, THD target_thd, enum_var_type type, std::string_view keycache_name)

const uchar *	value_ptr (THD *thd, enum_var_type type, std::string_view keycache_name)

my_option *	get_option ()

bool	set_default (THD thd, set_var var)
	Update the system variable with the default value from either session or global scope. More...

bool	update (THD thd, set_var var)

SHOW_TYPE	show_type ()

int	scope () const

const CHARSET_INFO *	charset (THD *thd)

bool	is_readonly () const

bool	not_visible () const

bool	is_trilevel () const

bool	is_persist_readonly () const

bool	is_parse_early () const

bool	is_sensitive () const

bool	is_hint_updateable () const
	Check if the variable can be set using SET_VAR hint. More...

bool	is_struct ()
	the following is only true for keycache variables, that support the syntax @keycache_name.variable_name More...

bool	is_written_to_binlog (enum_var_type type)

bool	check_scope (enum_var_type query_type)
	Return true for success if: Global query and variable scope is GLOBAL or SESSION, or Session query and variable scope is SESSION or ONLY_SESSION. More...

bool	is_global_persist (enum_var_type type)

bool	is_settable_at_command_line ()
	Return true if settable at the command line. More...

bool	register_option (std::vector< my_option > *array, int parse_flags)

void	do_deprecated_warning (THD *thd)

Item *	copy_value (THD *thd)
	Create item from system variable value. More...

void	save_default (THD thd, set_var var)

bool	check_if_sensitive_in_context (THD *, bool suppress_errors=true) const

Protected Member Functions
	Sys_var_alias (const char name_arg, sys_var &base_var, const char deprecation_substitute_arg, sys_var *persisted_alias, bool is_persisted_deprecated)
	Special constructor used to implement Sys_var_deprecated alias. More...

const uchar *	session_value_ptr (THD running_thd, THD target_thd, std::string_view keycache_name) override
	A pointer to a value of the variable for SHOW. More...

const uchar *	global_value_ptr (THD *thd, std::string_view keycache_name) override

Protected Member Functions inherited from sys_var
uchar *	session_var_ptr (THD *thd)
	A pointer to a storage area of the variable, to the raw data. More...

uchar *	global_var_ptr ()

Private Member Functions
bool	do_check (THD thd, set_var var) override

void	session_save_default (THD thd, set_var var) override
	save the session default value of the variable in var More...

void	global_save_default (THD thd, set_var var) override
	save the global default value of the variable in var More...

bool	session_update (THD thd, set_var var) override

bool	global_update (THD thd, set_var var) override

Private Attributes
sys_var &	m_base_var

Additional Inherited Members
Public Types inherited from sys_var
enum	flag_enum { GLOBAL = 0x0001 , SESSION = 0x0002 , ONLY_SESSION = 0x0004 , SCOPE_MASK = 0x03FF , READONLY = 0x0400 , ALLOCATED = 0x0800 , INVISIBLE = 0x1000 , TRI_LEVEL = 0x2000 , NOTPERSIST = 0x4000 , HINT_UPDATEABLE = 0x8000 , PERSIST_AS_READ_ONLY = 0x10000 , SENSITIVE = 0x20000 }

enum	binlog_status_enum { VARIABLE_NOT_IN_BINLOG , SESSION_VARIABLE_IN_BINLOG }
	Enumeration type to indicate for a system variable whether it will be written to the binlog or not. More...

Public Attributes inherited from sys_var
sys_var *	next

LEX_CSTRING	name

sys_var *	m_persisted_alias
	If the variable has an alias in the persisted variables file, this should point to it. More...

bool	m_is_persisted_deprecated
	If m_persist_alias is set, and the current variable is deprecated and m_persist_alias is the recommended substitute, then this flag should be set to true. More...

enum sys_var::binlog_status_enum	binlog_status
	Global system variable attributes. More...

std::map< std::string, std::string >	m_global_attributes

Static Public Attributes inherited from sys_var
static const int	PARSE_EARLY = 1

static const int	PARSE_NORMAL = 2

Protected Types inherited from sys_var
typedef bool(*	on_check_function) (sys_var self, THD thd, set_var *var)

typedef bool(*	pre_update_function) (sys_var self, THD thd, set_var *var)

typedef bool(*	on_update_function) (sys_var self, THD thd, enum_var_type type)

Protected Attributes inherited from sys_var
int	flags
	or'ed flag_enum values More...

int	m_parse_flag
	either PARSE_EARLY or PARSE_NORMAL. More...

const SHOW_TYPE	show_val_type
	what value_ptr() returns for sql_show.cc More...

my_option	option
	min, max, default values are stored here More...

PolyLock *	guard
	second lock that protects the variable More...

ptrdiff_t	offset
	offset to the value from global_system_variables More...

on_check_function	on_check

pre_update_function	pre_update
	Pointer to function to be invoked before updating system variable (but after calling on_check hook), while we do not hold any locks yet. More...

on_update_function	on_update

const char *const	deprecation_substitute

bool	is_os_charset
	true if the value is in character_set_filesystem More...

struct get_opt_arg_source	source

char	user [USERNAME_CHAR_LENGTH+1]

char	host [HOSTNAME_LENGTH+1]

ulonglong	timestamp

Detailed Description

A sys_var that is an alias for another sys_var.

The two variables effectively share (almost) all members, so whenever you change one of them, it affects both.

Usually you want to use Sys_var_deprecated_alias instead.

Constructor & Destructor Documentation

◆ Sys_var_alias() [1/2]

Sys_var_alias::Sys_var_alias	(	const char *	name_arg,
		sys_var &	base_var,
		const char *	deprecation_substitute_arg,
		sys_var *	persisted_alias,
		bool	is_persisted_deprecated
	)

inlineprotected

Special constructor used to implement Sys_var_deprecated alias.

Parameters

name_arg	The name of this sys_var.
base_var	The "parent" sys_var that this sys_var is an alias for.
deprecation_substitute_arg	The deprecation_substitute to use for this variable. While other fields in the created variable are inherited from real_var, the deprecation_substitute can be set using this parameter.
persisted_alias	When this variable is persisted, it will duplicate the entry in the persisted variables file: It will be stored both using the variable name name_arg, and the name of persisted_alias.
is_persisted_deprecated	If true, this variable is deprecated when appearing in the persisted variables file.

◆ Sys_var_alias() [2/2]

Sys_var_alias::Sys_var_alias	(	const char *	name_arg,
		sys_var &	base_var
	)

inline

Member Function Documentation

◆ cast_pluginvar()

sys_var_pluginvar * Sys_var_alias::cast_pluginvar ( )

inlineoverridevirtual

downcast for sys_var_pluginvar.

Returns this if it's an instance of sys_var_pluginvar, and 0 otherwise.

Reimplemented from sys_var.

◆ check_update_type()

bool Sys_var_alias::check_update_type ( Item_result type )

inlineoverridevirtual

Implements sys_var.

◆ cleanup()

void Sys_var_alias::cleanup ( void )

inlineoverridevirtual

All the cleanup procedures should be performed here.

Reimplemented from sys_var.

◆ do_check()

bool Sys_var_alias::do_check	(	THD *	thd,
		set_var *	var
	)

inlineoverrideprivatevirtual

Implements sys_var.

◆ get_base_var()

sys_var & Sys_var_alias::get_base_var ( )

inline

◆ get_default()

longlong Sys_var_alias::get_default ( )

inlineoverridevirtual

Reimplemented from sys_var.

◆ get_host()

const char * Sys_var_alias::get_host ( )

inlineoverridevirtual

Reimplemented from sys_var.

◆ get_max_value()

ulonglong Sys_var_alias::get_max_value ( )

inlineoverridevirtual

Reimplemented from sys_var.

◆ get_min_value()

longlong Sys_var_alias::get_min_value ( )

inlineoverridevirtual

Reimplemented from sys_var.

◆ get_source()

enum_variable_source Sys_var_alias::get_source ( )

inlineoverridevirtual

Reimplemented from sys_var.

◆ get_source_name()

const char * Sys_var_alias::get_source_name ( )

inlineoverridevirtual

Reimplemented from sys_var.

◆ get_timestamp()

ulonglong Sys_var_alias::get_timestamp ( ) const

inlineoverridevirtual

Reimplemented from sys_var.

◆ get_user()

const char * Sys_var_alias::get_user ( void )

inlineoverridevirtual

Reimplemented from sys_var.

◆ get_var_type()

ulong Sys_var_alias::get_var_type ( )

inlineoverridevirtual

Returns variable type.

Returns: variable type

Reimplemented from sys_var.

◆ global_save_default()

void Sys_var_alias::global_save_default	(	THD *	thd,
		set_var *	var
	)

inlineoverrideprivatevirtual

save the global default value of the variable in var

Implements sys_var.

◆ global_update()

bool Sys_var_alias::global_update	(	THD *	thd,
		set_var *	var
	)

inlineoverrideprivatevirtual

Implements sys_var.

◆ global_value_ptr()

const uchar * Sys_var_alias::global_value_ptr	(	THD *	thd,
		std::string_view	keycache_name
	)

inlineoverrideprotectedvirtual

Reimplemented from sys_var.

◆ is_non_persistent()

bool Sys_var_alias::is_non_persistent ( )

inlineoverridevirtual

Reimplemented from sys_var.

◆ saved_value_to_string()

void Sys_var_alias::saved_value_to_string	(	THD *	thd,
		set_var *	var,
		char *	def_val
	)

inlineoverridevirtual

This function converts value stored in save_result to string.

This function must be called after calling save_default() as save_default() will store default value to save_result.

Implements sys_var.

◆ session_save_default()

void Sys_var_alias::session_save_default	(	THD *	thd,
		set_var *	var
	)

inlineoverrideprivatevirtual

save the session default value of the variable in var

Implements sys_var.

◆ session_update()

bool Sys_var_alias::session_update	(	THD *	thd,
		set_var *	var
	)

inlineoverrideprivatevirtual

Implements sys_var.

◆ session_value_ptr()

const uchar * Sys_var_alias::session_value_ptr	(	THD *	running_thd,
		THD *	target_thd,
		std::string_view	keycache_name
	)

inlineoverrideprotectedvirtual

A pointer to a value of the variable for SHOW.

It must be of show_val_type type (bool for SHOW_BOOL, int for SHOW_INT, longlong for SHOW_LONGLONG, etc).

Reimplemented from sys_var.

◆ set_arg_source()

void Sys_var_alias::set_arg_source ( get_opt_arg_source * arg_source )

inlineoverridevirtual

Reimplemented from sys_var.

◆ set_host()

bool Sys_var_alias::set_host ( const char * hst )

inlineoverridevirtual

Reimplemented from sys_var.

◆ set_is_plugin()

void Sys_var_alias::set_is_plugin ( bool is_plugin )

inlineoverridevirtual

Reimplemented from sys_var.

◆ set_source()

void Sys_var_alias::set_source ( enum_variable_source src )

inlineoverridevirtual

Reimplemented from sys_var.

◆ set_source_name()

bool Sys_var_alias::set_source_name ( const char * path )

inlineoverridevirtual

Reimplemented from sys_var.

◆ set_timestamp() [1/2]

void Sys_var_alias::set_timestamp ( )

inlineoverridevirtual

Reimplemented from sys_var.

◆ set_timestamp() [2/2]

void Sys_var_alias::set_timestamp ( ulonglong ts )

inlineoverridevirtual

Reimplemented from sys_var.

◆ set_user()

bool Sys_var_alias::set_user ( const char * usr )

inlineoverridevirtual

Reimplemented from sys_var.

◆ set_user_host()

void Sys_var_alias::set_user_host ( THD * thd )

inlineoverridevirtual

Reimplemented from sys_var.

◆ update_default()

void Sys_var_alias::update_default ( longlong new_def_value )

inlineoverridevirtual

Reimplemented from sys_var.

Member Data Documentation

◆ m_base_var

sys_var& Sys_var_alias::m_base_var

private

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

sql/sys_vars.h

Public Member Functions

Protected Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Sys_var_alias() [1/2]

◆ Sys_var_alias() [2/2]

Member Function Documentation

◆ cast_pluginvar()

◆ check_update_type()

◆ cleanup()

◆ do_check()

◆ get_base_var()

◆ get_default()

◆ get_host()

◆ get_max_value()

◆ get_min_value()

◆ get_source()

◆ get_source_name()

◆ get_timestamp()

◆ get_user()

◆ get_var_type()

◆ global_save_default()

◆ global_update()

◆ global_value_ptr()

◆ is_non_persistent()

◆ saved_value_to_string()

◆ session_save_default()

◆ session_update()

◆ session_value_ptr()

◆ set_arg_source()

◆ set_host()

◆ set_is_plugin()

◆ set_source()

◆ set_source_name()

◆ set_timestamp() [1/2]

◆ set_timestamp() [2/2]

◆ set_user()

◆ set_user_host()

◆ update_default()

Member Data Documentation

◆ m_base_var