Adding upstream version 15.5.upstream/15.5

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 231 insertions, 0 deletions

diff --git a/src/include/utils/catcache.h b/src/include/utils/catcache.h
new file mode 100644
index 0000000..d81e6fa
--- /dev/null
+++ b/src/include/utils/catcache.h
@@ -0,0 +1,231 @@
+/*-------------------------------------------------------------------------
+ *
+ * catcache.h
+ *	  Low-level catalog cache definitions.
+ *
+ * NOTE: every catalog cache must have a corresponding unique index on
+ * the system table that it caches --- ie, the index must match the keys
+ * used to do lookups in this cache.  All cache fetches are done with
+ * indexscans (under normal conditions).  The index should be unique to
+ * guarantee that there can only be one matching row for a key combination.
+ *
+ *
+ * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/utils/catcache.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef CATCACHE_H
+#define CATCACHE_H
+
+#include "access/htup.h"
+#include "access/skey.h"
+#include "lib/ilist.h"
+#include "utils/relcache.h"
+
+/*
+ *		struct catctup:			individual tuple in the cache.
+ *		struct catclist:		list of tuples matching a partial key.
+ *		struct catcache:		information for managing a cache.
+ *		struct catcacheheader:	information for managing all the caches.
+ */
+
+#define CATCACHE_MAXKEYS		4
+
+
+/* function computing a datum's hash */
+typedef uint32 (*CCHashFN) (Datum datum);
+
+/* function computing equality of two datums */
+typedef bool (*CCFastEqualFN) (Datum a, Datum b);
+
+typedef struct catcache
+{
+	int			id;				/* cache identifier --- see syscache.h */
+	int			cc_nbuckets;	/* # of hash buckets in this cache */
+	TupleDesc	cc_tupdesc;		/* tuple descriptor (copied from reldesc) */
+	dlist_head *cc_bucket;		/* hash buckets */
+	CCHashFN	cc_hashfunc[CATCACHE_MAXKEYS];	/* hash function for each key */
+	CCFastEqualFN cc_fastequal[CATCACHE_MAXKEYS];	/* fast equal function for
+													 * each key */
+	int			cc_keyno[CATCACHE_MAXKEYS]; /* AttrNumber of each key */
+	dlist_head	cc_lists;		/* list of CatCList structs */
+	int			cc_ntup;		/* # of tuples currently in this cache */
+	int			cc_nkeys;		/* # of keys (1..CATCACHE_MAXKEYS) */
+	const char *cc_relname;		/* name of relation the tuples come from */
+	Oid			cc_reloid;		/* OID of relation the tuples come from */
+	Oid			cc_indexoid;	/* OID of index matching cache keys */
+	bool		cc_relisshared; /* is relation shared across databases? */
+	slist_node	cc_next;		/* list link */
+	ScanKeyData cc_skey[CATCACHE_MAXKEYS];	/* precomputed key info for heap
+											 * scans */
+
+	/*
+	 * Keep these at the end, so that compiling catcache.c with CATCACHE_STATS
+	 * doesn't break ABI for other modules
+	 */
+#ifdef CATCACHE_STATS
+	long		cc_searches;	/* total # searches against this cache */
+	long		cc_hits;		/* # of matches against existing entry */
+	long		cc_neg_hits;	/* # of matches against negative entry */
+	long		cc_newloads;	/* # of successful loads of new entry */
+
+	/*
+	 * cc_searches - (cc_hits + cc_neg_hits + cc_newloads) is number of failed
+	 * searches, each of which will result in loading a negative entry
+	 */
+	long		cc_invals;		/* # of entries invalidated from cache */
+	long		cc_lsearches;	/* total # list-searches */
+	long		cc_lhits;		/* # of matches against existing lists */
+#endif
+} CatCache;
+
+
+typedef struct catctup
+{
+	int			ct_magic;		/* for identifying CatCTup entries */
+#define CT_MAGIC   0x57261502
+
+	uint32		hash_value;		/* hash value for this tuple's keys */
+
+	/*
+	 * Lookup keys for the entry. By-reference datums point into the tuple for
+	 * positive cache entries, and are separately allocated for negative ones.
+	 */
+	Datum		keys[CATCACHE_MAXKEYS];
+
+	/*
+	 * Each tuple in a cache is a member of a dlist that stores the elements
+	 * of its hash bucket.  We keep each dlist in LRU order to speed repeated
+	 * lookups.
+	 */
+	dlist_node	cache_elem;		/* list member of per-bucket list */
+
+	/*
+	 * A tuple marked "dead" must not be returned by subsequent searches.
+	 * However, it won't be physically deleted from the cache until its
+	 * refcount goes to zero.  (If it's a member of a CatCList, the list's
+	 * refcount must go to zero, too; also, remember to mark the list dead at
+	 * the same time the tuple is marked.)
+	 *
+	 * A negative cache entry is an assertion that there is no tuple matching
+	 * a particular key.  This is just as useful as a normal entry so far as
+	 * avoiding catalog searches is concerned.  Management of positive and
+	 * negative entries is identical.
+	 */
+	int			refcount;		/* number of active references */
+	bool		dead;			/* dead but not yet removed? */
+	bool		negative;		/* negative cache entry? */
+	HeapTupleData tuple;		/* tuple management header */
+
+	/*
+	 * The tuple may also be a member of at most one CatCList.  (If a single
+	 * catcache is list-searched with varying numbers of keys, we may have to
+	 * make multiple entries for the same tuple because of this restriction.
+	 * Currently, that's not expected to be common, so we accept the potential
+	 * inefficiency.)
+	 */
+	struct catclist *c_list;	/* containing CatCList, or NULL if none */
+
+	CatCache   *my_cache;		/* link to owning catcache */
+	/* properly aligned tuple data follows, unless a negative entry */
+} CatCTup;
+
+
+/*
+ * A CatCList describes the result of a partial search, ie, a search using
+ * only the first K key columns of an N-key cache.  We store the keys used
+ * into the keys attribute to represent the stored key set.  The CatCList
+ * object contains links to cache entries for all the table rows satisfying
+ * the partial key.  (Note: none of these will be negative cache entries.)
+ *
+ * A CatCList is only a member of a per-cache list; we do not currently
+ * divide them into hash buckets.
+ *
+ * A list marked "dead" must not be returned by subsequent searches.
+ * However, it won't be physically deleted from the cache until its
+ * refcount goes to zero.  (A list should be marked dead if any of its
+ * member entries are dead.)
+ *
+ * If "ordered" is true then the member tuples appear in the order of the
+ * cache's underlying index.  This will be true in normal operation, but
+ * might not be true during bootstrap or recovery operations. (namespace.c
+ * is able to save some cycles when it is true.)
+ */
+typedef struct catclist
+{
+	int			cl_magic;		/* for identifying CatCList entries */
+#define CL_MAGIC   0x52765103
+
+	uint32		hash_value;		/* hash value for lookup keys */
+
+	dlist_node	cache_elem;		/* list member of per-catcache list */
+
+	/*
+	 * Lookup keys for the entry, with the first nkeys elements being valid.
+	 * All by-reference are separately allocated.
+	 */
+	Datum		keys[CATCACHE_MAXKEYS];
+
+	int			refcount;		/* number of active references */
+	bool		dead;			/* dead but not yet removed? */
+	bool		ordered;		/* members listed in index order? */
+	short		nkeys;			/* number of lookup keys specified */
+	int			n_members;		/* number of member tuples */
+	CatCache   *my_cache;		/* link to owning catcache */
+	CatCTup    *members[FLEXIBLE_ARRAY_MEMBER]; /* members */
+} CatCList;
+
+
+typedef struct catcacheheader
+{
+	slist_head	ch_caches;		/* head of list of CatCache structs */
+	int			ch_ntup;		/* # of tuples in all caches */
+} CatCacheHeader;
+
+
+/* this extern duplicates utils/memutils.h... */
+extern PGDLLIMPORT MemoryContext CacheMemoryContext;
+
+extern void CreateCacheMemoryContext(void);
+
+extern CatCache *InitCatCache(int id, Oid reloid, Oid indexoid,
+							  int nkeys, const int *key,
+							  int nbuckets);
+extern void InitCatCachePhase2(CatCache *cache, bool touch_index);
+
+extern HeapTuple SearchCatCache(CatCache *cache,
+								Datum v1, Datum v2, Datum v3, Datum v4);
+extern HeapTuple SearchCatCache1(CatCache *cache,
+								 Datum v1);
+extern HeapTuple SearchCatCache2(CatCache *cache,
+								 Datum v1, Datum v2);
+extern HeapTuple SearchCatCache3(CatCache *cache,
+								 Datum v1, Datum v2, Datum v3);
+extern HeapTuple SearchCatCache4(CatCache *cache,
+								 Datum v1, Datum v2, Datum v3, Datum v4);
+extern void ReleaseCatCache(HeapTuple tuple);
+
+extern uint32 GetCatCacheHashValue(CatCache *cache,
+								   Datum v1, Datum v2,
+								   Datum v3, Datum v4);
+
+extern CatCList *SearchCatCacheList(CatCache *cache, int nkeys,
+									Datum v1, Datum v2,
+									Datum v3);
+extern void ReleaseCatCacheList(CatCList *list);
+
+extern void ResetCatalogCaches(void);
+extern void CatalogCacheFlushCatalog(Oid catId);
+extern void CatCacheInvalidate(CatCache *cache, uint32 hashValue);
+extern void PrepareToInvalidateCacheTuple(Relation relation,
+										  HeapTuple tuple,
+										  HeapTuple newtuple,
+										  void (*function) (int, uint32, Oid));
+
+extern void PrintCatCacheLeakWarning(HeapTuple tuple);
+extern void PrintCatCacheListLeakWarning(CatCList *list);
+
+#endif							/* CATCACHE_H */