Gtid_mode Class Reference

Class to access the value of @global.gtid_mode in an efficient and thread-safe manner. More...

#include <rpl_gtid.h>

Public Types
enum	value_type {   OFF = 0 , DEFAULT = OFF , OFF_PERMISSIVE = 1 , ON_PERMISSIVE = 2 ,   ON = 3 }
	Possible values for @global.gtid_mode. More...

Public Member Functions
	Gtid_mode ()
void	set (value_type value)
	Set a new value for @global.gtid_mode. More...
value_type	get () const
	Return the current gtid_mode as an enumeration value. More...
const char *	get_string () const
	Return the current gtid_mode as a string. More...

Static Public Member Functions
static std::pair< bool, value_type >	from_string (std::string s)
	Return the given string gtid_mode as an enumeration value. More...
static const char *	to_string (value_type value)
	Return the given gtid_mode as a string. More...

Static Public Attributes
static ulong	sysvar_mode
	The sys_var framework needs a variable of type ulong to store the value in. More...
static const char *	names []
	Strings holding the enumeration values for gtid_mode. More...
static Checkable_rwlock	lock
	Protects updates to @global.gtid_mode. More...

Private Attributes
std::atomic< int >	m_atomic_mode

Detailed Description

Class to access the value of @global.gtid_mode in an efficient and thread-safe manner.

Member Enumeration Documentation

value_type

enum Gtid_mode::value_type

Possible values for @global.gtid_mode.

Enumerator
OFF	New transactions are anonymous. Replicated transactions must be anonymous; replicated GTID-transactions generate an error.
DEFAULT
OFF_PERMISSIVE	New transactions are anonyomus. Replicated transactions can be either anonymous or GTID-transactions.
ON_PERMISSIVE	New transactions are GTID-transactions. Replicated transactions can be either anonymous or GTID-transactions.
ON	New transactions are GTID-transactions. Replicated transactions must be GTID-transactions; replicated anonymous transactions generate an error.

Constructor & Destructor Documentation

Gtid_mode()

Gtid_mode::Gtid_mode ( )

inline

Member Function Documentation

from_string()

std::pair< bool, Gtid_mode::value_type > Gtid_mode::from_string ( std::string  s )

static

Return the given string gtid_mode as an enumeration value.

Parameters

s	The string to decode.

Returns

A pair, where the first component indicates failure and the second component is the GTID_MODE. Specifically, the first component is false if the string is a valid GTID_MODE, and true if it is not.

get()

Gtid_mode::value_type Gtid_mode::get

(

)

const

Return the current gtid_mode as an enumeration value.

get_string()

const char * Gtid_mode::get_string

(

)

const

Return the current gtid_mode as a string.

Used only for debugging. Non-debug code typically reads and acts on the enum value before printing it. Then it is better to print the enum value.

set()

void Gtid_mode::set

(

value_type

value

)

Set a new value for @global.gtid_mode.

This should only be called from Sys_var_gtid_mode::global_update and gtid_server_init.

to_string()

const char * Gtid_mode::to_string ( Gtid_mode::value_type  value )

static

Return the given gtid_mode as a string.

Member Data Documentation

lock

Checkable_rwlock Gtid_mode::lock

static

Initial value:

{
 
    key_rwlock_gtid_mode_lock
 
}

Protects updates to @global.gtid_mode.

SET @global.gtid_mode will try to take the write lock. If the lock is not granted immediately, SET will fail.

Thus, any other operation can block updates to @global.gtid_mode by acquiring the read lock.

m_atomic_mode

std::atomic<int> Gtid_mode::m_atomic_mode

private

names

const char * Gtid_mode::names

static

Initial value:

= {"OFF", "OFF_PERMISSIVE", "ON_PERMISSIVE",
                                  "ON", NullS}

Strings holding the enumeration values for gtid_mode.

Use Gtid_mode::get_string instead of accessing this directly.

sysvar_mode

ulong Gtid_mode::sysvar_mode

static

The sys_var framework needs a variable of type ulong to store the value in.

The sys_var framework takes the value from there, but we copy it (in the methods of sys_var_gtid_mode) to the atomic value Gtid_mode::mode, and use only that in all other places.

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

• sql/rpl_gtid.h
• sql/rpl_gtid_mode.cc