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/*-------------------------------------------------------------------------
*
* lockdefs.h
* Frontend exposed parts of postgres' low level lock mechanism
*
* The split between lockdefs.h and lock.h is not very principled. This file
* contains definition that have to (indirectly) be available when included by
* FRONTEND code.
*
* Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* src/include/storage/lockdefs.h
*
*-------------------------------------------------------------------------
*/
#ifndef LOCKDEFS_H_
#define LOCKDEFS_H_
/*
* LOCKMODE is an integer (1..N) indicating a lock type. LOCKMASK is a bit
* mask indicating a set of held or requested lock types (the bit 1<<mode
* corresponds to a particular lock mode).
*/
typedef int LOCKMASK;
typedef int LOCKMODE;
/*
* These are the valid values of type LOCKMODE for all the standard lock
* methods (both DEFAULT and USER).
*/
/* NoLock is not a lock mode, but a flag value meaning "don't get a lock" */
#define NoLock 0
#define AccessShareLock 1 /* SELECT */
#define RowShareLock 2 /* SELECT FOR UPDATE/FOR SHARE */
#define RowExclusiveLock 3 /* INSERT, UPDATE, DELETE */
#define ShareUpdateExclusiveLock 4 /* VACUUM (non-FULL), ANALYZE, CREATE
* INDEX CONCURRENTLY */
#define ShareLock 5 /* CREATE INDEX (WITHOUT CONCURRENTLY) */
#define ShareRowExclusiveLock 6 /* like EXCLUSIVE MODE, but allows ROW
* SHARE */
#define ExclusiveLock 7 /* blocks ROW SHARE/SELECT...FOR UPDATE */
#define AccessExclusiveLock 8 /* ALTER TABLE, DROP TABLE, VACUUM FULL,
* and unqualified LOCK TABLE */
#define MaxLockMode 8 /* highest standard lock mode */
/* WAL representation of an AccessExclusiveLock on a table */
typedef struct xl_standby_lock
{
TransactionId xid; /* xid of holder of AccessExclusiveLock */
Oid dbOid; /* DB containing table */
Oid relOid; /* OID of table */
} xl_standby_lock;
#endif /* LOCKDEFS_H_ */