From fa83d38bfd1ad868b22ad5fc390447be81c1c704 Mon Sep 17 00:00:00 2001
From: Peter Geoghegan <pg@bowt.ie>
Date: Mon, 18 Nov 2019 19:35:30 -0800
Subject: [PATCH v25 4/4] DEBUG: Show index values in pageinspect

This is not intended for commit.  It is included as a convenience for
reviewers.
---
 contrib/pageinspect/btreefuncs.c       | 65 ++++++++++++++++++--------
 contrib/pageinspect/expected/btree.out |  2 +-
 2 files changed, 47 insertions(+), 20 deletions(-)

diff --git a/contrib/pageinspect/btreefuncs.c b/contrib/pageinspect/btreefuncs.c
index 17f7ad186e..4eab8df098 100644
--- a/contrib/pageinspect/btreefuncs.c
+++ b/contrib/pageinspect/btreefuncs.c
@@ -27,6 +27,7 @@
 
 #include "postgres.h"
 
+#include "access/genam.h"
 #include "access/nbtree.h"
 #include "access/relation.h"
 #include "catalog/namespace.h"
@@ -245,6 +246,7 @@ bt_page_stats(PG_FUNCTION_ARGS)
  */
 struct user_args
 {
+	Relation	rel;
 	Page		page;
 	OffsetNumber offset;
 	bool		leafpage;
@@ -261,6 +263,7 @@ struct user_args
 static Datum
 bt_page_print_tuples(FuncCallContext *fctx, struct user_args *uargs)
 {
+	Relation	rel = uargs->rel;
 	Page		page = uargs->page;
 	OffsetNumber offset = uargs->offset;
 	bool		leafpage = uargs->leafpage;
@@ -295,26 +298,48 @@ bt_page_print_tuples(FuncCallContext *fctx, struct user_args *uargs)
 	values[j++] = BoolGetDatum(IndexTupleHasVarwidths(itup));
 
 	ptr = (char *) itup + IndexInfoFindDataOffset(itup->t_info);
-	dlen = IndexTupleSize(itup) - IndexInfoFindDataOffset(itup->t_info);
-
-	/*
-	 * Make sure that "data" column does not include posting list or pivot
-	 * tuple representation of heap TID
-	 */
-	if (BTreeTupleIsPosting(itup))
-		dlen -= IndexTupleSize(itup) - BTreeTupleGetPostingOffset(itup);
-	else if (BTreeTupleIsPivot(itup) && BTreeTupleGetHeapTID(itup) != NULL)
-		dlen -= MAXALIGN(sizeof(ItemPointerData));
-
-	dump = palloc0(dlen * 3 + 1);
-	datacstring = dump;
-	for (off = 0; off < dlen; off++)
+	if (rel)
 	{
-		if (off > 0)
-			*dump++ = ' ';
-		sprintf(dump, "%02x", *(ptr + off) & 0xff);
-		dump += 2;
+		TupleDesc	itupdesc = RelationGetDescr(rel);
+		Datum		datvalues[INDEX_MAX_KEYS];
+		bool		isnull[INDEX_MAX_KEYS];
+		int			natts;
+		int			indnkeyatts = rel->rd_index->indnkeyatts;
+
+		natts = BTreeTupleGetNAtts(itup, rel);
+
+		itupdesc->natts = Min(indnkeyatts, natts);
+		memset(&isnull, 0xFF, sizeof(isnull));
+		index_deform_tuple(itup, itupdesc, datvalues, isnull);
+		rel->rd_index->indnkeyatts = natts;
+		datacstring = BuildIndexValueDescription(rel, datvalues, isnull);
+		itupdesc->natts = IndexRelationGetNumberOfAttributes(rel);
+		rel->rd_index->indnkeyatts = indnkeyatts;
 	}
+	else
+	{
+		dlen = IndexTupleSize(itup) - IndexInfoFindDataOffset(itup->t_info);
+
+		/*
+		 * Make sure that "data" column does not include posting list or pivot
+		 * tuple representation of heap TID
+		 */
+		if (BTreeTupleIsPosting(itup))
+			dlen -= IndexTupleSize(itup) - BTreeTupleGetPostingOffset(itup);
+		else if (BTreeTupleIsPivot(itup) && BTreeTupleGetHeapTID(itup) != NULL)
+			dlen -= MAXALIGN(sizeof(ItemPointerData));
+
+		dump = palloc0(dlen * 3 + 1);
+		datacstring = dump;
+		for (off = 0; off < dlen; off++)
+		{
+			if (off > 0)
+				*dump++ = ' ';
+			sprintf(dump, "%02x", *(ptr + off) & 0xff);
+			dump += 2;
+		}
+	}
+
 	values[j++] = CStringGetTextDatum(datacstring);
 	pfree(datacstring);
 
@@ -437,11 +462,11 @@ bt_page_items(PG_FUNCTION_ARGS)
 
 		uargs = palloc(sizeof(struct user_args));
 
+		uargs->rel = rel;
 		uargs->page = palloc(BLCKSZ);
 		memcpy(uargs->page, BufferGetPage(buffer), BLCKSZ);
 
 		UnlockReleaseBuffer(buffer);
-		relation_close(rel, AccessShareLock);
 
 		uargs->offset = FirstOffsetNumber;
 
@@ -475,6 +500,7 @@ bt_page_items(PG_FUNCTION_ARGS)
 	}
 	else
 	{
+		relation_close(uargs->rel, AccessShareLock);
 		pfree(uargs->page);
 		pfree(uargs);
 		SRF_RETURN_DONE(fctx);
@@ -522,6 +548,7 @@ bt_page_items_bytea(PG_FUNCTION_ARGS)
 
 		uargs = palloc(sizeof(struct user_args));
 
+		uargs->rel = NULL;
 		uargs->page = VARDATA(raw_page);
 
 		uargs->offset = FirstOffsetNumber;
diff --git a/contrib/pageinspect/expected/btree.out b/contrib/pageinspect/expected/btree.out
index 1d45cd5c1e..3da5f37c3e 100644
--- a/contrib/pageinspect/expected/btree.out
+++ b/contrib/pageinspect/expected/btree.out
@@ -40,7 +40,7 @@ ctid       | (0,1)
 itemlen    | 16
 nulls      | f
 vars       | f
-data       | 01 00 00 00 00 00 00 01
+data       | (a)=(72057594037927937)
 dead       | f
 htid       | (0,1)
 tids       | 
-- 
2.17.1