Merge from PG master upto d5cb3bab564e0927ffac7c8729eacf181a12dd40

This is the result of the "git merge remotes/PGSQL/master" upto the said commit
point. We have done some basic analysis, fixed compilation problems etc, but
bulk of the logical problems in conflict resolution etc will be handled by
subsequent commits.

1 files changed, 362 insertions, 12 deletions

diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c
index 6084589e07..03b387f6b6 100644
--- a/contrib/pgstattuple/pgstatindex.c
+++ b/contrib/pgstattuple/pgstatindex.c
@@ -29,6 +29,7 @@
 
 #include "access/gin_private.h"
 #include "access/heapam.h"
+#include "access/hash.h"
 #include "access/htup_details.h"
 #include "access/nbtree.h"
 #include "catalog/namespace.h"
@@ -36,8 +37,10 @@
 #include "funcapi.h"
 #include "miscadmin.h"
 #include "storage/bufmgr.h"
+#include "storage/lmgr.h"
 #include "utils/builtins.h"
 #include "utils/rel.h"
+#include "utils/varlena.h"
 
 
 /*
@@ -53,10 +56,20 @@ PG_FUNCTION_INFO_V1(pgstatindexbyid);
 PG_FUNCTION_INFO_V1(pg_relpages);
 PG_FUNCTION_INFO_V1(pg_relpagesbyid);
 PG_FUNCTION_INFO_V1(pgstatginindex);
+PG_FUNCTION_INFO_V1(pgstathashindex);
+
+PG_FUNCTION_INFO_V1(pgstatindex_v1_5);
+PG_FUNCTION_INFO_V1(pgstatindexbyid_v1_5);
+PG_FUNCTION_INFO_V1(pg_relpages_v1_5);
+PG_FUNCTION_INFO_V1(pg_relpagesbyid_v1_5);
+PG_FUNCTION_INFO_V1(pgstatginindex_v1_5);
+
+Datum		pgstatginindex_internal(Oid relid, FunctionCallInfo fcinfo);
 
 #define IS_INDEX(r) ((r)->rd_rel->relkind == RELKIND_INDEX)
 #define IS_BTREE(r) ((r)->rd_rel->relam == BTREE_AM_OID)
 #define IS_GIN(r) ((r)->rd_rel->relam == GIN_AM_OID)
+#define IS_HASH(r) ((r)->rd_rel->relam == HASH_AM_OID)
 
 /* ------------------------------------------------
  * A structure for a whole btree index statistics
@@ -93,18 +106,44 @@ typedef struct GinIndexStat
 	int64		pending_tuples;
 } GinIndexStat;
 
+/* ------------------------------------------------
+ * A structure for a whole HASH index statistics
+ * used by pgstathashindex().
+ * ------------------------------------------------
+ */
+typedef struct HashIndexStat
+{
+	int32		version;
+	int32		space_per_page;
+
+	BlockNumber bucket_pages;
+	BlockNumber overflow_pages;
+	BlockNumber bitmap_pages;
+	BlockNumber unused_pages;
+
+	int64		live_items;
+	int64		dead_items;
+	uint64		free_space;
+} HashIndexStat;
+
 static Datum pgstatindex_impl(Relation rel, FunctionCallInfo fcinfo);
+static void GetHashPageStats(Page page, HashIndexStat *stats);
+static void check_relation_relkind(Relation rel);
 
 /* ------------------------------------------------------
  * pgstatindex()
  *
  * Usage: SELECT * FROM pgstatindex('t1_pkey');
+ *
+ * The superuser() check here must be kept as the library might be upgraded
+ * without the extension being upgraded, meaning that in pre-1.5 installations
+ * these functions could be called by any user.
  * ------------------------------------------------------
  */
 Datum
 pgstatindex(PG_FUNCTION_ARGS)
 {
-	text	   *relname = PG_GETARG_TEXT_P(0);
+	text	   *relname = PG_GETARG_TEXT_PP(0);
 	Relation	rel;
 	RangeVar   *relrv;
 
@@ -119,6 +158,31 @@ pgstatindex(PG_FUNCTION_ARGS)
 	PG_RETURN_DATUM(pgstatindex_impl(rel, fcinfo));
 }
 
+/*
+ * As of pgstattuple version 1.5, we no longer need to check if the user
+ * is a superuser because we REVOKE EXECUTE on the function from PUBLIC.
+ * Users can then grant access to it based on their policies.
+ *
+ * Otherwise identical to pgstatindex (above).
+ */
+Datum
+pgstatindex_v1_5(PG_FUNCTION_ARGS)
+{
+	text	   *relname = PG_GETARG_TEXT_PP(0);
+	Relation	rel;
+	RangeVar   *relrv;
+
+	relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
+	rel = relation_openrv(relrv, AccessShareLock);
+
+	PG_RETURN_DATUM(pgstatindex_impl(rel, fcinfo));
+}
+
+/*
+ * The superuser() check here must be kept as the library might be upgraded
+ * without the extension being upgraded, meaning that in pre-1.5 installations
+ * these functions could be called by any user.
+ */
 Datum
 pgstatindexbyid(PG_FUNCTION_ARGS)
 {
@@ -135,6 +199,18 @@ pgstatindexbyid(PG_FUNCTION_ARGS)
 	PG_RETURN_DATUM(pgstatindex_impl(rel, fcinfo));
 }
 
+/* No need for superuser checks in v1.5, see above */
+Datum
+pgstatindexbyid_v1_5(PG_FUNCTION_ARGS)
+{
+	Oid			relid = PG_GETARG_OID(0);
+	Relation	rel;
+
+	rel = relation_open(relid, AccessShareLock);
+
+	PG_RETURN_DATUM(pgstatindex_impl(rel, fcinfo));
+}
+
 static Datum
 pgstatindex_impl(Relation rel, FunctionCallInfo fcinfo)
 {
@@ -145,8 +221,10 @@ pgstatindex_impl(Relation rel, FunctionCallInfo fcinfo)
 	BufferAccessStrategy bstrategy = GetAccessStrategy(BAS_BULKREAD);
 
 	if (!IS_INDEX(rel) || !IS_BTREE(rel))
-		elog(ERROR, "relation \"%s\" is not a btree index",
-			 RelationGetRelationName(rel));
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("relation \"%s\" is not a btree index",
+						RelationGetRelationName(rel))));
 
 	/*
 	 * Reject attempts to read non-local temporary relations; we would be
@@ -292,12 +370,14 @@ pgstatindex_impl(Relation rel, FunctionCallInfo fcinfo)
  *
  * Usage: SELECT pg_relpages('t1');
  *		  SELECT pg_relpages('t1_pkey');
+ *
+ * Must keep superuser() check, see above.
  * --------------------------------------------------------
  */
 Datum
 pg_relpages(PG_FUNCTION_ARGS)
 {
-	text	   *relname = PG_GETARG_TEXT_P(0);
+	text	   *relname = PG_GETARG_TEXT_PP(0);
 	int64		relpages;
 	Relation	rel;
 	RangeVar   *relrv;
@@ -310,6 +390,9 @@ pg_relpages(PG_FUNCTION_ARGS)
 	relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
 	rel = relation_openrv(relrv, AccessShareLock);
 
+	/* only some relkinds have storage */
+	check_relation_relkind(rel);
+
 	/* note: this will work OK on non-local temp tables */
 
 	relpages = RelationGetNumberOfBlocks(rel);
@@ -319,6 +402,31 @@ pg_relpages(PG_FUNCTION_ARGS)
 	PG_RETURN_INT64(relpages);
 }
 
+/* No need for superuser checks in v1.5, see above */
+Datum
+pg_relpages_v1_5(PG_FUNCTION_ARGS)
+{
+	text	   *relname = PG_GETARG_TEXT_PP(0);
+	int64		relpages;
+	Relation	rel;
+	RangeVar   *relrv;
+
+	relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
+	rel = relation_openrv(relrv, AccessShareLock);
+
+	/* only some relkinds have storage */
+	check_relation_relkind(rel);
+
+	/* note: this will work OK on non-local temp tables */
+
+	relpages = RelationGetNumberOfBlocks(rel);
+
+	relation_close(rel, AccessShareLock);
+
+	PG_RETURN_INT64(relpages);
+}
+
+/* Must keep superuser() check, see above. */
 Datum
 pg_relpagesbyid(PG_FUNCTION_ARGS)
 {
@@ -333,6 +441,31 @@ pg_relpagesbyid(PG_FUNCTION_ARGS)
 
 	rel = relation_open(relid, AccessShareLock);
 
+	/* only some relkinds have storage */
+	check_relation_relkind(rel);
+
+	/* note: this will work OK on non-local temp tables */
+
+	relpages = RelationGetNumberOfBlocks(rel);
+
+	relation_close(rel, AccessShareLock);
+
+	PG_RETURN_INT64(relpages);
+}
+
+/* No need for superuser checks in v1.5, see above */
+Datum
+pg_relpagesbyid_v1_5(PG_FUNCTION_ARGS)
+{
+	Oid			relid = PG_GETARG_OID(0);
+	int64		relpages;
+	Relation	rel;
+
+	rel = relation_open(relid, AccessShareLock);
+
+	/* only some relkinds have storage */
+	check_relation_relkind(rel);
+
 	/* note: this will work OK on non-local temp tables */
 
 	relpages = RelationGetNumberOfBlocks(rel);
@@ -346,12 +479,35 @@ pg_relpagesbyid(PG_FUNCTION_ARGS)
  * pgstatginindex()
  *
  * Usage: SELECT * FROM pgstatginindex('ginindex');
+ *
+ * Must keep superuser() check, see above.
  * ------------------------------------------------------
  */
 Datum
 pgstatginindex(PG_FUNCTION_ARGS)
 {
 	Oid			relid = PG_GETARG_OID(0);
+
+	if (!superuser())
+		ereport(ERROR,
+				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+				 (errmsg("must be superuser to use pgstattuple functions"))));
+
+	PG_RETURN_DATUM(pgstatginindex_internal(relid, fcinfo));
+}
+
+/* No need for superuser checks in v1.5, see above */
+Datum
+pgstatginindex_v1_5(PG_FUNCTION_ARGS)
+{
+	Oid			relid = PG_GETARG_OID(0);
+
+	PG_RETURN_DATUM(pgstatginindex_internal(relid, fcinfo));
+}
+
+Datum
+pgstatginindex_internal(Oid relid, FunctionCallInfo fcinfo)
+{
 	Relation	rel;
 	Buffer		buffer;
 	Page		page;
@@ -363,16 +519,13 @@ pgstatginindex(PG_FUNCTION_ARGS)
 	bool		nulls[3] = {false, false, false};
 	Datum		result;
 
-	if (!superuser())
-		ereport(ERROR,
-				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
-				 (errmsg("must be superuser to use pgstattuple functions"))));
-
 	rel = relation_open(relid, AccessShareLock);
 
 	if (!IS_INDEX(rel) || !IS_GIN(rel))
-		elog(ERROR, "relation \"%s\" is not a GIN index",
-			 RelationGetRelationName(rel));
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("relation \"%s\" is not a GIN index",
+						RelationGetRelationName(rel))));
 
 	/*
 	 * Reject attempts to read non-local temporary relations; we would be
@@ -415,5 +568,202 @@ pgstatginindex(PG_FUNCTION_ARGS)
 	tuple = heap_form_tuple(tupleDesc, values, nulls);
 	result = HeapTupleGetDatum(tuple);
 
-	PG_RETURN_DATUM(result);
+	return (result);
+}
+
+/* ------------------------------------------------------
+ * pgstathashindex()
+ *
+ * Usage: SELECT * FROM pgstathashindex('hashindex');
+ * ------------------------------------------------------
+ */
+Datum
+pgstathashindex(PG_FUNCTION_ARGS)
+{
+	Oid			relid = PG_GETARG_OID(0);
+	BlockNumber nblocks;
+	BlockNumber blkno;
+	Relation	rel;
+	HashIndexStat stats;
+	BufferAccessStrategy bstrategy;
+	HeapTuple	tuple;
+	TupleDesc	tupleDesc;
+	Datum		values[8];
+	bool		nulls[8];
+	Buffer		metabuf;
+	HashMetaPage metap;
+	float8		free_percent;
+	uint64		total_space;
+
+	rel = index_open(relid, AccessShareLock);
+
+	/* index_open() checks that it's an index */
+	if (!IS_HASH(rel))
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("relation \"%s\" is not a HASH index",
+						RelationGetRelationName(rel))));
+
+
+	/*
+	 * Reject attempts to read non-local temporary relations; we would be
+	 * likely to get wrong data since we have no visibility into the owning
+	 * session's local buffers.
+	 */
+	if (RELATION_IS_OTHER_TEMP(rel))
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+			   errmsg("cannot access temporary indexes of other sessions")));
+
+	/* Get the information we need from the metapage. */
+	memset(&stats, 0, sizeof(stats));
+	metabuf = _hash_getbuf(rel, HASH_METAPAGE, HASH_READ, LH_META_PAGE);
+	metap = HashPageGetMeta(BufferGetPage(metabuf));
+	stats.version = metap->hashm_version;
+	stats.space_per_page = metap->hashm_bsize;
+	_hash_relbuf(rel, metabuf);
+
+	/* Get the current relation length */
+	nblocks = RelationGetNumberOfBlocks(rel);
+
+	/* prepare access strategy for this index */
+	bstrategy = GetAccessStrategy(BAS_BULKREAD);
+
+	/* Start from blkno 1 as 0th block is metapage */
+	for (blkno = 1; blkno < nblocks; blkno++)
+	{
+		Buffer		buf;
+		Page		page;
+
+		CHECK_FOR_INTERRUPTS();
+
+		buf = ReadBufferExtended(rel, MAIN_FORKNUM, blkno, RBM_NORMAL,
+								 bstrategy);
+		LockBuffer(buf, BUFFER_LOCK_SHARE);
+		page = (Page) BufferGetPage(buf);
+
+		if (PageIsNew(page))
+			stats.unused_pages++;
+		else if (PageGetSpecialSize(page) !=
+				 MAXALIGN(sizeof(HashPageOpaqueData)))
+			ereport(ERROR,
+					(errcode(ERRCODE_INDEX_CORRUPTED),
+				   errmsg("index \"%s\" contains corrupted page at block %u",
+						  RelationGetRelationName(rel),
+						  BufferGetBlockNumber(buf))));
+		else
+		{
+			HashPageOpaque opaque;
+			int			pagetype;
+
+			opaque = (HashPageOpaque) PageGetSpecialPointer(page);
+			pagetype = opaque->hasho_flag & LH_PAGE_TYPE;
+
+			if (pagetype == LH_BUCKET_PAGE)
+			{
+				stats.bucket_pages++;
+				GetHashPageStats(page, &stats);
+			}
+			else if (pagetype == LH_OVERFLOW_PAGE)
+			{
+				stats.overflow_pages++;
+				GetHashPageStats(page, &stats);
+			}
+			else if (pagetype == LH_BITMAP_PAGE)
+				stats.bitmap_pages++;
+			else if (pagetype == LH_UNUSED_PAGE)
+				stats.unused_pages++;
+			else
+				ereport(ERROR,
+						(errcode(ERRCODE_INDEX_CORRUPTED),
+						 errmsg("unexpected page type 0x%04X in HASH index \"%s\" block %u",
+							opaque->hasho_flag, RelationGetRelationName(rel),
+								BufferGetBlockNumber(buf))));
+		}
+		UnlockReleaseBuffer(buf);
+	}
+
+	/* Done accessing the index */
+	index_close(rel, AccessShareLock);
+
+	/* Count unused pages as free space. */
+	stats.free_space += stats.unused_pages * stats.space_per_page;
+
+	/*
+	 * Total space available for tuples excludes the metapage and the bitmap
+	 * pages.
+	 */
+	total_space = (nblocks - (stats.bitmap_pages + 1)) * stats.space_per_page;
+
+	if (total_space == 0)
+		free_percent = 0.0;
+	else
+		free_percent = 100.0 * stats.free_space / total_space;
+
+	/*
+	 * Build a tuple descriptor for our result type
+	 */
+	if (get_call_result_type(fcinfo, NULL, &tupleDesc) != TYPEFUNC_COMPOSITE)
+		elog(ERROR, "return type must be a row type");
+
+	tupleDesc = BlessTupleDesc(tupleDesc);
+
+	/*
+	 * Build and return the tuple
+	 */
+	MemSet(nulls, 0, sizeof(nulls));
+	values[0] = Int32GetDatum(stats.version);
+	values[1] = Int64GetDatum((int64) stats.bucket_pages);
+	values[2] = Int64GetDatum((int64) stats.overflow_pages);
+	values[3] = Int64GetDatum((int64) stats.bitmap_pages);
+	values[4] = Int64GetDatum((int64) stats.unused_pages);
+	values[5] = Int64GetDatum(stats.live_items);
+	values[6] = Int64GetDatum(stats.dead_items);
+	values[7] = Float8GetDatum(free_percent);
+	tuple = heap_form_tuple(tupleDesc, values, nulls);
+
+	PG_RETURN_DATUM(HeapTupleGetDatum(tuple));
+}
+
+/* -------------------------------------------------
+ * GetHashPageStatis()
+ *
+ * Collect statistics of single hash page
+ * -------------------------------------------------
+ */
+static void
+GetHashPageStats(Page page, HashIndexStat *stats)
+{
+	OffsetNumber maxoff = PageGetMaxOffsetNumber(page);
+	int			off;
+
+	/* count live and dead tuples, and free space */
+	for (off = FirstOffsetNumber; off <= maxoff; off++)
+	{
+		ItemId		id = PageGetItemId(page, off);
+
+		if (!ItemIdIsDead(id))
+			stats->live_items++;
+		else
+			stats->dead_items++;
+	}
+	stats->free_space += PageGetExactFreeSpace(page);
+}
+
+/*
+ * check_relation_relkind - convenience routine to check that relation
+ * is of the relkind supported by the callers
+ */
+static void
+check_relation_relkind(Relation rel)
+{
+	if (rel->rd_rel->relkind != RELKIND_RELATION &&
+		rel->rd_rel->relkind != RELKIND_INDEX &&
+		rel->rd_rel->relkind != RELKIND_MATVIEW &&
+		rel->rd_rel->relkind != RELKIND_SEQUENCE &&
+		rel->rd_rel->relkind != RELKIND_TOASTVALUE)
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("\"%s\" is not a table, index, materialized view, sequence, or TOAST table",
+						RelationGetRelationName(rel))));
 }