sys_var_pluginvar Class Reference

#include <sql_plugin_var.h>

Inheritance diagram for sys_var_pluginvar:

Public Member Functions
	sys_var_pluginvar (sys_var_chain *chain, const char *name_arg, SYS_VAR *plugin_var_arg)
sys_var_pluginvar *	cast_pluginvar () override
	downcast for sys_var_pluginvar. More...
bool	check_update_type (Item_result type) override
SHOW_TYPE	show_type ()
uchar *	real_value_ptr (THD *thd, enum_var_type type)
TYPELIB *	plugin_var_typelib (void)
uchar *	do_value_ptr (THD *running_thd, THD *target_thd, enum_var_type type, std::string_view keycache_name)
uchar *	do_value_ptr (THD *thd, enum_var_type type, std::string_view keycache_name)
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
bool	do_check (THD *thd, set_var *var) override
void	session_save_default (THD *, set_var *) override
	save the session default value of the variable in var More...
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...
void	global_save_default (THD *, set_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
longlong	get_min_value () override
ulonglong	get_max_value () override
void	set_arg_source (get_opt_arg_source *src) override
bool	is_non_persistent () override
void	set_is_plugin (bool val) 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 ()
virtual void	cleanup ()
	All the cleanup procedures should be performed here. More...
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)
virtual void	update_default (longlong new_def_value)
virtual longlong	get_default ()
virtual ulong	get_var_type ()
	Returns variable type. More...
virtual enum_variable_source	get_source ()
virtual const char *	get_source_name ()
virtual void	set_source (enum_variable_source src)
virtual bool	set_source_name (const char *path)
virtual bool	set_user (const char *usr)
virtual const char *	get_user ()
virtual const char *	get_host ()
virtual bool	set_host (const char *hst)
virtual ulonglong	get_timestamp () const
virtual void	set_user_host (THD *thd)
my_option *	get_option ()
virtual void	set_timestamp ()
virtual void	set_timestamp (ulonglong ts)
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

Static Public Member Functions
static void *	operator new (size_t size, MEM_ROOT *mem_root, const std::nothrow_t &arg=std::nothrow) noexcept
static void *	operator new (size_t size)
static void	operator delete (void *ptr_arg, size_t size)
static void	operator delete (void *, MEM_ROOT *, const std::nothrow_t &) noexcept
static void	operator delete (void *ptr)

Public Attributes
bool	is_plugin
st_plugin_int *	plugin {nullptr}
SYS_VAR *	plugin_var
const char *	orig_pluginvar_name
	variable name from whatever is hard-coded in the plugin source and doesn't have pluginname- prefix is replaced by an allocated name with a plugin prefix. 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 Private Member Functions
static bool	on_check_pluginvar (sys_var *self, THD *, set_var *var)
	Enforce the NO DEFAULT policy for plugin system variables. More...

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...
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 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 ()
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

Constructor & Destructor Documentation

sys_var_pluginvar()

sys_var_pluginvar::sys_var_pluginvar ( sys_var_chain *  chain, const char *  name_arg, SYS_VAR *  plugin_var_arg  )

inline

Member Function Documentation

cast_pluginvar()

sys_var_pluginvar * sys_var_pluginvar::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_pluginvar::check_update_type ( Item_result  type )

overridevirtual

Implements sys_var.

do_check()

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

overridevirtual

Implements sys_var.

do_value_ptr() [1/2]

uchar * sys_var_pluginvar::do_value_ptr	(	THD *	running_thd,
		THD *	target_thd,
		enum_var_type	type,
		std::string_view	keycache_name
	)

do_value_ptr() [2/2]

uchar * sys_var_pluginvar::do_value_ptr ( THD *  thd, enum_var_type  type, std::string_view  keycache_name  )

inline

get_max_value()

ulonglong sys_var_pluginvar::get_max_value ( )

overridevirtual

Reimplemented from sys_var.

get_min_value()

longlong sys_var_pluginvar::get_min_value ( )

overridevirtual

Reimplemented from sys_var.

global_save_default()

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

inlineoverridevirtual

save the global default value of the variable in var

Implements sys_var.

global_update()

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

overridevirtual

Implements sys_var.

global_value_ptr()

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

inlineoverridevirtual

Reimplemented from sys_var.

is_non_persistent()

bool sys_var_pluginvar::is_non_persistent ( )

inlineoverridevirtual

Reimplemented from sys_var.

on_check_pluginvar()

bool sys_var_pluginvar::on_check_pluginvar ( sys_var *  self, THD *  , set_var *  var  )

staticprivate

Enforce the NO DEFAULT policy for plugin system variables.

A plugin variable does not explicitly call the plugin supplied check function when setting the default value, e.g. SET <plugin_var> = DEFAULT.

But when the PLUGIN_VAR_NODEFAULT is set setting the default value is prohibited. This function gets called after the actual check done by sys_var_pluginvar::do_check() so it does not need to check again.

it only needs to enforce the PLUGIN_VAR_NODEFAULT flag.

There's no need for special error hence just returning true is enough.

See also

sys_var::on_check_function, sys_var::check, sys_var_pluginvar::do_check(), PLUGIN_VAR_NODEFAULT

Parameters

self	the sys_var structure for the variable being set
var	the data about the value being set

Returns

is the setting valid

Return values

true	not valid
false	valid

operator delete() [1/3]

static void sys_var_pluginvar::operator delete ( void *  , MEM_ROOT *  , const std::nothrow_t &    )

inlinestaticnoexcept

operator delete() [2/3]

static void sys_var_pluginvar::operator delete ( void *  ptr )

inlinestatic

operator delete() [3/3]

static void sys_var_pluginvar::operator delete ( void *  ptr_arg, size_t  size  )

inlinestatic

operator new() [1/2]

static void * sys_var_pluginvar::operator new ( size_t  size )

inlinestatic

operator new() [2/2]

static void * sys_var_pluginvar::operator new ( size_t  size, MEM_ROOT *  mem_root, const std::nothrow_t &  arg = std::nothrow  )

inlinestaticnoexcept

plugin_var_typelib()

TYPELIB * sys_var_pluginvar::plugin_var_typelib

(

void

)

real_value_ptr()

uchar * sys_var_pluginvar::real_value_ptr	(	THD *	thd,
		enum_var_type	type
	)

saved_value_to_string()

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

overridevirtual

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_pluginvar::session_save_default ( THD *  thd, set_var *  var  )

inlineoverridevirtual

save the session default value of the variable in var

Implements sys_var.

session_update()

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

overridevirtual

Implements sys_var.

session_value_ptr()

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

inlineoverridevirtual

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_pluginvar::set_arg_source ( get_opt_arg_source *  src )

inlineoverridevirtual

Reimplemented from sys_var.

set_is_plugin()

void sys_var_pluginvar::set_is_plugin ( bool  val )

inlineoverridevirtual

Reimplemented from sys_var.

show_type()

SHOW_TYPE sys_var_pluginvar::show_type

(

)

Member Data Documentation

is_plugin

bool sys_var_pluginvar::is_plugin

orig_pluginvar_name

const char* sys_var_pluginvar::orig_pluginvar_name

variable name from whatever is hard-coded in the plugin source and doesn't have pluginname- prefix is replaced by an allocated name with a plugin prefix.

When plugin is uninstalled we need to restore the pointer to point to the hard-coded value, because plugin may be installed/uninstalled many times without reloading the shared object.

plugin

st_plugin_int* sys_var_pluginvar::plugin {nullptr}

plugin_var

SYS_VAR* sys_var_pluginvar::plugin_var

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

• sql/sql_plugin_var.h
• sql/sql_plugin_var.cc