sys_vars_shared.h File Reference

"protected" interface to sys_var - server configuration variables. More...

#include "mysql/psi/mysql_mutex.h"
#include "mysql/psi/mysql_thread.h"
#include "sql/sql_table.h"

Go to the source code of this file.

Classes
class	PolyLock
	wrapper to hide a mutex and an rwlock under a common interface More...
class	PolyLock_mutex
class	PolyLock_rwlock
class	PolyLock_lock_log
class	AutoWLock
class	AutoRLock

Functions
bool	throw_bounds_warning (THD *thd, const char *name, bool fixed, bool is_unsigned, longlong v)
	Throw warning (error in STRICT mode) if value for variable needed bounding. More...
bool	throw_bounds_warning (THD *thd, const char *name, bool fixed, double v)
sys_var *	find_static_system_variable (const std::string &name)
	Find a static system variable. More...
sys_var *	find_dynamic_system_variable (const std::string &name)
	Find a dynamic system variable. More...
sys_var *	intern_find_sys_var (const char *str, size_t length)
	Find a system variable, either static or dynamic. More...

Detailed Description

"protected" interface to sys_var - server configuration variables.

This header is included by files implementing support and utility functions of sys_var's (set_var.cc) and files implementing classes in the sys_var hierarchy (sql_plugin.cc)

Function Documentation

find_dynamic_system_variable()

sys_var * find_dynamic_system_variable

(

const std::string &

name

)

Find a dynamic system variable.

Parameters

name	Name of system variable to find

Return values

pointer	pointer to variable definitions
nullptr	1. Unknown static variable (error message is given). Invisible static variable (no error message).

Note

Requires an external lock on LOCK_system_variable_hash.

find_static_system_variable()

sys_var * find_static_system_variable

(

const std::string &

name

)

Find a static system variable.

Parameters

name	Name of system variable to find

Return values

pointer	pointer to variable definitions
nullptr	1. Unknown static variable (error message is given). Invisible static variable (no error message).

Note

Unlike intern_find_sys_var() and find_dynamic_system_variable(), an external lock on LOCK_system_variable_hash is not necessary.

intern_find_sys_var()

sys_var * intern_find_sys_var	(	const char *	str,
		size_t	length
	)

Find a system variable, either static or dynamic.

Parameters

str	Name of system variable to find
length	Length of variable. zero means that we should use strlen() on the variable

Return values

pointer	pointer to variable definitions
nullptr	1. Unknown variable (error message is given). Invisible variable (no error message).

Note

Requires an external lock on LOCK_system_variable_hash.

throw_bounds_warning() [1/2]

bool throw_bounds_warning	(	THD *	thd,
		const char *	name,
		bool	fixed,
		bool	is_unsigned,
		longlong	v
	)

Throw warning (error in STRICT mode) if value for variable needed bounding.

Plug-in interface also uses this.

Parameters

thd	thread handle
name	variable's name
fixed	did we have to correct the value? (throw warn/err if so)
is_unsigned	is value's type unsigned?
v	variable's value

Return values

true	on error, false otherwise (warning or ok)

throw_bounds_warning() [2/2]

bool throw_bounds_warning	(	THD *	thd,
		const char *	name,
		bool	fixed,
		double	v
	)