Replace many MemSet calls with struct initialization

This replaces all MemSet() calls with struct initialization where that
is easily and obviously possible.  (For example, some cases have to
worry about padding bits, so I left those.)

(The same could be done with appropriate memset() calls, but this
patch is part of an effort to phase out MemSet(), so it doesn't touch
memset() calls.)

Reviewed-by: Ranier Vilela <ranier.vf@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://www.postgresql.org/message-id/9847b13c-b785-f4e2-75c3-12ec77a3b05c@enterprisedb.com

3 files changed, 8 insertions, 23 deletions

diff --git a/contrib/pageinspect/brinfuncs.c b/contrib/pageinspect/brinfuncs.c
index 879276e6dec..f4c959ecab9 100644
--- a/contrib/pageinspect/brinfuncs.c
+++ b/contrib/pageinspect/brinfuncs.c
@@ -202,7 +202,7 @@ brin_page_items(PG_FUNCTION_ARGS)
 	for (;;)
 	{
 		Datum		values[7];
-		bool		nulls[7];
+		bool		nulls[7] = {0};
 
 		/*
 		 * This loop is called once for every attribute of every tuple in the
@@ -230,8 +230,6 @@ brin_page_items(PG_FUNCTION_ARGS)
 		else
 			attno++;
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		if (unusedItem)
 		{
 			values[0] = UInt16GetDatum(offset);
@@ -334,7 +332,7 @@ brin_metapage_info(PG_FUNCTION_ARGS)
 	BrinMetaPageData *meta;
 	TupleDesc	tupdesc;
 	Datum		values[4];
-	bool		nulls[4];
+	bool		nulls[4] = {0};
 	HeapTuple	htup;
 
 	if (!superuser())
@@ -354,7 +352,6 @@ brin_metapage_info(PG_FUNCTION_ARGS)
 
 	/* Extract values from the metapage */
 	meta = (BrinMetaPageData *) PageGetContents(page);
-	MemSet(nulls, 0, sizeof(nulls));
 	values[0] = CStringGetTextDatum(psprintf("0x%08X", meta->brinMagic));
 	values[1] = Int32GetDatum(meta->brinVersion);
 	values[2] = Int32GetDatum(meta->pagesPerRange);
diff --git a/contrib/pageinspect/hashfuncs.c b/contrib/pageinspect/hashfuncs.c
index 5287dbe1a30..81815392d70 100644
--- a/contrib/pageinspect/hashfuncs.c
+++ b/contrib/pageinspect/hashfuncs.c
@@ -238,7 +238,7 @@ hash_page_stats(PG_FUNCTION_ARGS)
 	Page		page;
 	int			j;
 	Datum		values[9];
-	bool		nulls[9];
+	bool		nulls[9] = {0};
 	HashPageStat stat;
 	HeapTuple	tuple;
 	TupleDesc	tupleDesc;
@@ -261,8 +261,6 @@ hash_page_stats(PG_FUNCTION_ARGS)
 		elog(ERROR, "return type must be a row type");
 	tupleDesc = BlessTupleDesc(tupleDesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	j = 0;
 	values[j++] = Int32GetDatum(stat.live_items);
 	values[j++] = Int32GetDatum(stat.dead_items);
@@ -303,7 +301,7 @@ hash_page_items(PG_FUNCTION_ARGS)
 	Page		page;
 	Datum		result;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 	uint32		hashkey;
 	HeapTuple	tuple;
 	FuncCallContext *fctx;
@@ -361,8 +359,6 @@ hash_page_items(PG_FUNCTION_ARGS)
 
 		itup = (IndexTuple) PageGetItem(uargs->page, id);
 
-		MemSet(nulls, 0, sizeof(nulls));
-
 		j = 0;
 		values[j++] = Int32GetDatum((int32) uargs->offset);
 		values[j++] = PointerGetDatum(&itup->t_tid);
@@ -409,7 +405,7 @@ hash_bitmap_info(PG_FUNCTION_ARGS)
 	int			i,
 				j;
 	Datum		values[3];
-	bool		nulls[3];
+	bool		nulls[3] = {0};
 	uint32	   *freep;
 
 	if (!superuser())
@@ -495,8 +491,6 @@ hash_bitmap_info(PG_FUNCTION_ARGS)
 		elog(ERROR, "return type must be a row type");
 	tupleDesc = BlessTupleDesc(tupleDesc);
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	j = 0;
 	values[j++] = Int64GetDatum((int64) bitmapblkno);
 	values[j++] = Int32GetDatum(bitmapbit);
@@ -526,7 +520,7 @@ hash_metapage_info(PG_FUNCTION_ARGS)
 	int			i,
 				j;
 	Datum		values[16];
-	bool		nulls[16];
+	bool		nulls[16] = {0};
 	Datum		spares[HASH_MAX_SPLITPOINTS];
 	Datum		mapp[HASH_MAX_BITMAPS];
 
@@ -544,8 +538,6 @@ hash_metapage_info(PG_FUNCTION_ARGS)
 
 	metad = HashPageGetMeta(page);
 
-	MemSet(nulls, 0, sizeof(nulls));
-
 	j = 0;
 	values[j++] = Int64GetDatum((int64) metad->hashm_magic);
 	values[j++] = Int64GetDatum((int64) metad->hashm_version);
diff --git a/contrib/pageinspect/heapfuncs.c b/contrib/pageinspect/heapfuncs.c
index a654234c6bd..2ff70405cf8 100644
--- a/contrib/pageinspect/heapfuncs.c
+++ b/contrib/pageinspect/heapfuncs.c
@@ -507,8 +507,8 @@ Datum
 heap_tuple_infomask_flags(PG_FUNCTION_ARGS)
 {
 #define HEAP_TUPLE_INFOMASK_COLS 2
-	Datum		values[HEAP_TUPLE_INFOMASK_COLS];
-	bool		nulls[HEAP_TUPLE_INFOMASK_COLS];
+	Datum		values[HEAP_TUPLE_INFOMASK_COLS] = {0};
+	bool		nulls[HEAP_TUPLE_INFOMASK_COLS] = {0};
 	uint16		t_infomask = PG_GETARG_INT16(0);
 	uint16		t_infomask2 = PG_GETARG_INT16(1);
 	int			cnt = 0;
@@ -530,10 +530,6 @@ heap_tuple_infomask_flags(PG_FUNCTION_ARGS)
 	bitcnt = pg_popcount((const char *) &t_infomask, sizeof(uint16)) +
 		pg_popcount((const char *) &t_infomask2, sizeof(uint16));
 
-	/* Initialize values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* If no flags, return a set of empty arrays */
 	if (bitcnt <= 0)
 	{