*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/access/index/genam.c,v 1.21 1999/07/17 20:16:40 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/access/index/genam.c,v 1.22 1999/12/30 05:04:50 tgl Exp $
*
* NOTES
* many of the old access method routines have been turned into
* All other states cannot occur.
*
* Note:
- *It would be possible to cache the status of the previous and
+ * It would be possible to cache the status of the previous and
* next item pointer using the flags.
* ----------------------------------------------------------------
*/
* We don't know how the various AMs do locking, however, so we don't
* do anything about that here.
*
- * The intent is that an AM implementor will define a front-end routine
- * that calls this one, to fill in the scan, and then does whatever kind
- * of locking he wants.
+ * The intent is that an AM implementor will define a beginscan routine
+ * that calls RelationGetIndexScan, to fill in the scan, and then does
+ * whatever kind of locking he wants.
+ *
+ * At the end of a scan, the AM's endscan routine undoes the locking,
+ * but does *not* call IndexScanEnd --- the higher-level index_endscan
+ * routine does that. (We can't do it in the AM because index_endscan
+ * still needs to touch the IndexScanDesc after calling the AM.)
+ *
+ * Because of this, the AM does not have a choice whether to call
+ * RelationGetIndexScan or not; its beginscan routine must return an
+ * object made by RelationGetIndexScan. This is kinda ugly but not
+ * worth cleaning up now.
* ----------------------------------------------------------------
*/
* relation -- index relation for scan.
* scanFromEnd -- if true, begin scan at one of the index's
* endpoints.
- * numberOfKeys -- count of scan keys (more than one won't
- * necessarily do anything useful, yet).
+ * numberOfKeys -- count of scan keys.
* key -- the ScanKey for the starting position of the scan.
*
* Returns:
* An initialized IndexScanDesc.
- *
- * Side Effects:
- * Bumps the ref count on the relation to keep it in the cache.
- *
* ----------------
*/
IndexScanDesc
return scan;
}
+/* ----------------
+ * IndexScanEnd -- End an index scan.
+ *
+ * This routine just releases the storage acquired by
+ * RelationGetIndexScan(). Any AM-level resources are
+ * assumed to already have been released by the AM's
+ * endscan routine.
+ *
+ * Returns:
+ * None.
+ * ----------------
+ */
+void
+IndexScanEnd(IndexScanDesc scan)
+{
+ if (!IndexScanIsValid(scan))
+ elog(ERROR, "IndexScanEnd: invalid scan");
+
+ if (scan->keyData != NULL)
+ pfree(scan->keyData);
+
+ pfree(scan);
+}
+
#ifdef NOT_USED
/* ----------------
* IndexScanRestart -- Restart an index scan.
}
/* ----------------
- * IndexScanEnd -- End and index scan.
- *
- * This routine is not used by any existing access method, but is
- * suitable for use if you don't want to do sophisticated locking.
- *
- * Returns:
- * None.
- *
- * Side Effects:
- * None.
- * ----------------
- */
-void
-IndexScanEnd(IndexScanDesc scan)
-{
- if (!IndexScanIsValid(scan))
- elog(ERROR, "IndexScanEnd: invalid scan");
-
- pfree(scan);
-}
-
-
-/* ----------------
* IndexScanMarkPosition -- Mark current position in a scan.
*
* This routine isn't used by any existing access method, but is the
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/access/index/indexam.c,v 1.37 1999/11/07 23:07:54 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/access/index/indexam.c,v 1.38 1999/12/30 05:04:50 tgl Exp $
*
* INTERFACE ROUTINES
* index_open - open an index relation by relationId
UnlockRelation(scan->relation, AccessShareLock);
RelationDecrementReferenceCount(scan->relation);
+
+ /* Release the scan data structure itself */
+ IndexScanEnd(scan);
}
/* ----------------
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/catalog/indexing.c,v 1.54 1999/12/16 22:19:39 wieck Exp $
+ * $Header: /cvsroot/pgsql/src/backend/catalog/indexing.c,v 1.55 1999/12/30 05:04:55 tgl Exp $
*
*-------------------------------------------------------------------------
*/
}
index_endscan(sd);
- pfree(sd);
+
return result;
}
NAMEDATALEN, RelationGetRelationName(relation));
index_endscan(sd);
- pfree(sd);
index_close(irel);
heap_close(tgrel, AccessShareLock);
elog(ERROR, "Constraint '%s' does not exist", (char *)lfirst(l));
index_endscan(sd);
-
}
index_close(irel);
heap_close(tgrel, AccessShareLock);
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/storage/large_object/inv_api.c,v 1.63 1999/12/16 22:19:51 wieck Exp $
+ * $Header: /cvsroot/pgsql/src/backend/storage/large_object/inv_api.c,v 1.64 1999/12/30 05:05:03 tgl Exp $
*
*-------------------------------------------------------------------------
*/
if (obj_desc->iscan != (IndexScanDesc) NULL)
{
index_endscan(obj_desc->iscan);
- pfree(obj_desc->iscan);
obj_desc->iscan = NULL;
}
return;
index_endscan(obj_desc->iscan);
- pfree(obj_desc->iscan);
obj_desc->iscan = (IndexScanDesc) NULL;
ItemPointerSetInvalid(&(obj_desc->htid));
if (res == (RetrieveIndexResult) NULL)
{
index_endscan(iscan);
- pfree(iscan);
return 0;
}
/* don't need the index scan anymore */
index_endscan(iscan);
- pfree(iscan);
/* get olastbyte attribute */
d = heap_getattr(&tuple, 1, hdesc, &isNull);
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/regproc.c,v 1.46 1999/12/16 22:19:52 wieck Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/adt/regproc.c,v 1.47 1999/12/30 05:05:07 tgl Exp $
*
*-------------------------------------------------------------------------
*/
}
index_endscan(sd);
- pfree(sd);
index_close(idesc);
heap_close(hdesc, AccessShareLock);
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/cache/relcache.c,v 1.83 1999/12/28 13:40:49 wieck Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/cache/relcache.c,v 1.84 1999/12/30 05:05:11 tgl Exp $
*
*-------------------------------------------------------------------------
*/
AllocateRelationDesc(Relation relation, u_int natts,
Form_pg_class relp)
{
- Size len;
Form_pg_class relationForm;
/* ----------------
* allocate space for the relation tuple form
* ----------------
*/
- relationForm = (Form_pg_class)
- palloc((Size) (sizeof(FormData_pg_class)));
+ relationForm = (Form_pg_class) palloc(sizeof(FormData_pg_class));
- memmove((char *) relationForm, (char *) relp, CLASS_TUPLE_SIZE);
+ memcpy((char *) relationForm, (char *) relp, CLASS_TUPLE_SIZE);
/* ----------------
* allocate space for new relation descriptor, if needed
*/
- len = sizeof(RelationData);
-
if (relation == NULL)
- relation = (Relation) palloc(len);
+ relation = (Relation) palloc(sizeof(RelationData));
/* ----------------
* clear new reldesc
* ----------------
*/
- MemSet((char *) relation, 0, len);
+ MemSet((char *) relation, 0, sizeof(RelationData));
/* make sure relation is marked as having no open file yet */
relation->rd_fd = -1;
u_int natts;
Oid relid;
Oid relam;
+ HeapTuple pg_class_tuple;
Form_pg_class relp;
-
MemoryContext oldcxt;
- HeapTuple pg_class_tuple;
-
- oldcxt = MemoryContextSwitchTo((MemoryContext) CacheCxt);
-
/* ----------------
* find the tuple in pg_class corresponding to the given relation id
* ----------------
* ----------------
*/
if (!HeapTupleIsValid(pg_class_tuple))
- {
- MemoryContextSwitchTo(oldcxt);
-
return NULL;
- }
/* ----------------
* get information from the pg_class_tuple
/* ----------------
* allocate storage for the relation descriptor,
* initialize relation->rd_rel and get the access method id.
+ * The storage is allocated in memory context CacheCxt.
* ----------------
*/
+ oldcxt = MemoryContextSwitchTo((MemoryContext) CacheCxt);
relation = AllocateRelationDesc(oldrelation, natts, relp);
relam = relation->rd_rel->relam;
*/
RelationCacheInsert(relation);
+ MemoryContextSwitchTo(oldcxt);
+
/* -------------------
* free the memory allocated for pg_class_tuple
* and for lock data pointed to by pg_class_tuple
*/
heap_freetuple(pg_class_tuple);
- MemoryContextSwitchTo(oldcxt);
-
return relation;
}
ndef - found, RelationGetRelationName(relation));
index_endscan(sd);
- pfree(sd);
index_close(irel);
heap_close(adrel, AccessShareLock);
}
ncheck - found, RelationGetRelationName(relation));
index_endscan(sd);
- pfree(sd);
index_close(irel);
heap_close(rcrel, AccessShareLock);
}
*
* Copyright (c) 1994, Regents of the University of California
*
- * $Id: genam.h,v 1.20 1999/07/16 17:07:25 momjian Exp $
+ * $Id: genam.h,v 1.21 1999/12/30 05:05:13 tgl Exp $
*
*-------------------------------------------------------------------------
*/
/* in genam.c */
extern IndexScanDesc RelationGetIndexScan(Relation relation, bool scanFromEnd,
uint16 numberOfKeys, ScanKey key);
+extern void IndexScanEnd(IndexScanDesc scan);
#endif /* GENAM_H */
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