polardbxengine/sql/log_table.h

138 lines
3.6 KiB
C++

/* Copyright (c) 2000, 2019, Alibaba and/or its affiliates. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License, version 2.0,
as published by the Free Software Foundation.
This program is also distributed with certain software (including
but not limited to OpenSSL) that is licensed under separate terms,
as designated in a particular file or component or in included license
documentation. The authors of MySQL hereby grant you an additional
permission to link the program and your derivative works with the
separately licensed software that they have included with MySQL.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License, version 2.0, for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
#ifndef SQL_LOG_TABLE_H_INCLUDED
#define SQL_LOG_TABLE_H_INCLUDED
#include "sql/log.h"
#include "sql/mdl.h"
#include "sql/sql_class.h"
class THD;
/**
Log table management
@Note
Some features on Log table (slow_log/general_log)
- Rotate table data file when flush log table
Some variables:
- rotate_log_table Determined whether enable it when
flush slow logs
- rotate_log_table_last_name
Last rotated file name
*/
namespace im {
/**
Last rotated file name.
It will display './DATABASE/FILE.EXT' format name
when show global variables, and it is not protected
by any lock, we think it is safe even though there
will may be concurrent update.
*/
extern char rotate_log_table_last_name[];
extern char *rotate_log_table_last_name_ptr;
extern void update_rotate_log_table_last_name_ptr();
/**
Struture used to save current runtime context
*/
struct Statement_context {
Statement_context(){};
~Statement_context(){};
/* Option_bits */
ulonglong m_thd_option_bits;
/* Opened tables and MDL savepoint */
Open_tables_backup m_open_tables_state;
};
/* Log table management */
class Log_table {
public:
Log_table(THD *thd, enum_log_table_type log_table_type)
: m_thd(thd),
m_log_table_type(log_table_type),
m_ctx_state(),
m_table_list(nullptr),
m_backup(false) {}
~Log_table();
/**
Validate and backup current context.
@retval true Failure
@retval false Success
*/
bool validate_and_backup_context();
/**
Rotate the target log table data file.
@retval true Failure
@retval false Success
*/
bool rotate_table();
private:
/**
Lock the target log table, report error if failed.
@retval true Failure
@retval false Success
*/
bool lock_log_table();
private:
/* Runtime connection */
THD *m_thd;
/* Target log table type */
enum_log_table_type m_log_table_type;
/* Temporary saved context */
Statement_context m_ctx_state;
/* Temporary created table_list object */
TABLE_LIST *m_table_list;
/* Whether already backup context */
bool m_backup;
};
/**
Rotate log table.
@param[in] thd current thread
@param[in] log_table_type Slow_log or general_log
@retval true Failure
@retval false Success
*/
extern bool rotate_log_table(THD *thd, enum_log_table_type log_table_type);
} /* namespace im */
#endif