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/*-------------------------------------------------------------------------
*
* lockcmds.c
* Lock command support code
*
* Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/commands/lockcmds.c,v 1.8 2003/11/29 19:51:47 pgsql Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/heapam.h"
#include "catalog/namespace.h"
#include "commands/lockcmds.h"
#include "miscadmin.h"
#include "utils/acl.h"
#include "utils/lsyscache.h"
/*
* LOCK TABLE
*/
void
LockTableCommand(LockStmt *lockstmt)
{
List *p;
/*
* Iterate over the list and open, lock, and close the relations one
* at a time
*/
foreach(p, lockstmt->relations)
{
RangeVar *relation = lfirst(p);
Oid reloid;
AclResult aclresult;
Relation rel;
/*
* We don't want to open the relation until we've checked
* privilege. So, manually get the relation OID.
*/
reloid = RangeVarGetRelid(relation, false);
if (lockstmt->mode == AccessShareLock)
aclresult = pg_class_aclcheck(reloid, GetUserId(),
ACL_SELECT);
else
aclresult = pg_class_aclcheck(reloid, GetUserId(),
ACL_UPDATE | ACL_DELETE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, ACL_KIND_CLASS,
get_rel_name(reloid));
rel = relation_open(reloid, lockstmt->mode);
/* Currently, we only allow plain tables to be locked */
if (rel->rd_rel->relkind != RELKIND_RELATION)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a table",
relation->relname)));
relation_close(rel, NoLock); /* close rel, keep lock */
}
}
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