| Current Path : /usr/include/mysql/mysql/ |
Linux gator3171.hostgator.com 4.19.286-203.ELK.el7.x86_64 #1 SMP Wed Jun 14 04:33:55 CDT 2023 x86_64 |
| Current File : //usr/include/mysql/mysql/service_locking.h |
/*
Copyright (c) 2015, Oracle 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 as published by
the Free Software Foundation; version 2 of the License.
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 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 SERVICE_LOCKING_INCLUDED
#define SERVICE_LOCKING_INCLUDED
/*
This service provides support for taking read/write locks.
It is intended for use with fabric, but it is still a general
service. The locks are in a separate namespace from other
locks in the server, and there is also no interactions with
transactions (i.e. locks are not released on commit/abort).
These locks are implemented using the metadata lock (MDL) subsystem
and thus deadlocks involving locking service locks and other types
of metadata will be detected using the MDL deadlock detector.
*/
#ifdef __cplusplus
class THD;
#define MYSQL_THD THD*
#else
#define MYSQL_THD void*
#endif
#ifdef __cplusplus
extern "C" {
#endif
/**
Types of locking service locks.
LOCKING_SERVICE_READ is compatible with LOCKING_SERVICE_READ.
All other combinations are incompatible.
*/
enum enum_locking_service_lock_type
{ LOCKING_SERVICE_READ, LOCKING_SERVICE_WRITE };
extern struct mysql_locking_service_st {
/**
Acquire locking service locks.
@param opaque_thd Thread handle. If NULL, current_thd will be used.
@param lock_namespace Namespace of the locks to acquire.
@param lock_names Array of names of the locks to acquire.
@param lock_num Number of elements in 'lock_names'.
@param lock_type Lock type to acquire. LOCKING_SERVICE_READ or _WRITE.
@param lock_timeout Number of seconds to wait before giving up.
@retval 1 Acquisition failed, error has been reported.
@retval 0 Acquisition successful, all locks acquired.
@note both lock_namespace and lock_names are limited to 64 characters max.
Names are compared using binary comparison.
*/
int (*mysql_acquire_locks)(MYSQL_THD opaque_thd, const char* lock_namespace,
const char**lock_names, size_t lock_num,
enum enum_locking_service_lock_type lock_type,
unsigned long lock_timeout);
/**
Release all lock service locks taken by the given connection
in the given namespace.
@param opaque_thd Thread handle. If NULL, current_thd will be used.
@param lock_namespace Namespace of the locks to release.
@retval 1 Release failed, error has been reported.
@retval 0 Release successful, all locks acquired.
*/
int (*mysql_release_locks)(MYSQL_THD opaque_thd, const char* lock_namespace);
} *mysql_locking_service;
#ifdef MYSQL_DYNAMIC_PLUGIN
#define mysql_acquire_locking_service_locks(_THD, _NAMESPACE, _NAMES, _NUM, \
_TYPE, _TIMEOUT) \
mysql_locking_service->mysql_acquire_locks(_THD, _NAMESPACE, _NAMES, _NUM, \
_TYPE, _TIMEOUT)
#define mysql_release_locking_service_locks(_THD, _NAMESPACE) \
mysql_locking_service->mysql_release_locks(_THD, _NAMESPACE)
#else
int mysql_acquire_locking_service_locks(MYSQL_THD opaque_thd,
const char* lock_namespace,
const char**lock_names,
size_t lock_num,
enum enum_locking_service_lock_type lock_type,
unsigned long lock_timeout);
int mysql_release_locking_service_locks(MYSQL_THD opaque_thd,
const char* lock_namespace);
#endif /* MYSQL_DYNAMIC_PLUGIN */
#ifdef __cplusplus
}
#endif
#endif /* SERVICE_LOCKING_INCLUDED */