database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-10-18 04:29:09 +03:00
Code Activity

Mark ItemPointer arguments as const in tuple/table lock functions

Browse Source 
The functions LockTuple, ConditionalLockTuple, UnlockTuple, and
XactLockTableWait take an ItemPointer argument that they do not
modify, so the argument can be const-qualified to better convey intent
and allow the compiler to enforce immutability.

Author: Chao Li <li.evan.chao@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAEoWx2m9e4rECHBwpRE4%2BGCH%2BpbYZXLh2f4rB1Du5hDfKug%2BOg%40mail.gmail.com
This commit is contained in:
Peter Eisentraut
2025-08-29 07:33:50 +02:00
parent 710e6c4301
commit 991295f387
2 changed files with 9 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
src/backend/storage/lmgr/lmgr.c
View File

@@ -55,7 +55,7 @@ typedef struct XactLockTableWaitInfo
{
XLTW_Oper oper;
Relation rel;
ItemPointer ctid;
const ItemPointerData *ctid;
} XactLockTableWaitInfo;
static void XactLockTableWaitErrorCb(void *arg);
@@ -559,7 +559,7 @@ UnlockPage(Relation relation, BlockNumber blkno, LOCKMODE lockmode)
* tuple. See heap_lock_tuple before using this!
*/
void
LockTuple(Relation relation, ItemPointer tid, LOCKMODE lockmode)
LockTuple(Relation relation, const ItemPointerData *tid, LOCKMODE lockmode)
{
LOCKTAG tag;
@@ -579,7 +579,7 @@ LockTuple(Relation relation, ItemPointer tid, LOCKMODE lockmode)
* Returns true iff the lock was acquired.
*/
bool
ConditionalLockTuple(Relation relation, ItemPointer tid, LOCKMODE lockmode,
ConditionalLockTuple(Relation relation, const ItemPointerData *tid, LOCKMODE lockmode,
bool logLockFailure)
{
LOCKTAG tag;
@@ -598,7 +598,7 @@ ConditionalLockTuple(Relation relation, ItemPointer tid, LOCKMODE lockmode,
* UnlockTuple
*/
void
UnlockTuple(Relation relation, ItemPointer tid, LOCKMODE lockmode)
UnlockTuple(Relation relation, const ItemPointerData *tid, LOCKMODE lockmode)
{
LOCKTAG tag;
@@ -660,7 +660,7 @@ XactLockTableDelete(TransactionId xid)
* and if so wait for its parent.
*/
void
XactLockTableWait(TransactionId xid, Relation rel, ItemPointer ctid,
XactLockTableWait(TransactionId xid, Relation rel, const ItemPointerData *ctid,
XLTW_Oper oper)
{
LOCKTAG tag;

8
src/include/storage/lmgr.h
View File

@@ -71,16 +71,16 @@ extern bool ConditionalLockPage(Relation relation, BlockNumber blkno, LOCKMODE l
extern void UnlockPage(Relation relation, BlockNumber blkno, LOCKMODE lockmode);
/* Lock a tuple (see heap_lock_tuple before assuming you understand this) */
extern void LockTuple(Relation relation, ItemPointer tid, LOCKMODE lockmode);
extern bool ConditionalLockTuple(Relation relation, ItemPointer tid,
extern void LockTuple(Relation relation, const ItemPointerData *tid, LOCKMODE lockmode);
extern bool ConditionalLockTuple(Relation relation, const ItemPointerData *tid,
LOCKMODE lockmode, bool logLockFailure);
extern void UnlockTuple(Relation relation, ItemPointer tid, LOCKMODE lockmode);
extern void UnlockTuple(Relation relation, const ItemPointerData *tid, LOCKMODE lockmode);
/* Lock an XID (used to wait for a transaction to finish) */
extern void XactLockTableInsert(TransactionId xid);
extern void XactLockTableDelete(TransactionId xid);
extern void XactLockTableWait(TransactionId xid, Relation rel,
ItemPointer ctid, XLTW_Oper oper);
const ItemPointerData *ctid, XLTW_Oper oper);
extern bool ConditionalXactLockTableWait(TransactionId xid,
bool logLockFailure);