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

1 files changed, 14 insertions, 38 deletions

diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 893690dad52..d9e2a793829 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -488,13 +488,10 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 	{
 		LocalPgBackendStatus *local_beentry;
 		PgBackendStatus *beentry;
-		Datum		values[PG_STAT_GET_PROGRESS_COLS];
-		bool		nulls[PG_STAT_GET_PROGRESS_COLS];
+		Datum		values[PG_STAT_GET_PROGRESS_COLS] = {0};
+		bool		nulls[PG_STAT_GET_PROGRESS_COLS] = {0};
 		int			i;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
 
 		if (!local_beentry)
@@ -551,17 +548,14 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 	for (curr_backend = 1; curr_backend <= num_backends; curr_backend++)
 	{
 		/* for each row */
-		Datum		values[PG_STAT_GET_ACTIVITY_COLS];
-		bool		nulls[PG_STAT_GET_ACTIVITY_COLS];
+		Datum		values[PG_STAT_GET_ACTIVITY_COLS] = {0};
+		bool		nulls[PG_STAT_GET_ACTIVITY_COLS] = {0};
 		LocalPgBackendStatus *local_beentry;
 		PgBackendStatus *beentry;
 		PGPROC	   *proc;
 		const char *wait_event_type = NULL;
 		const char *wait_event = NULL;
 
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
-
 		/* Get the next one in the list */
 		local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
 		if (!local_beentry)
@@ -1747,15 +1741,11 @@ pg_stat_get_wal(PG_FUNCTION_ARGS)
 {
 #define PG_STAT_GET_WAL_COLS	9
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_GET_WAL_COLS];
-	bool		nulls[PG_STAT_GET_WAL_COLS];
+	Datum		values[PG_STAT_GET_WAL_COLS] = {0};
+	bool		nulls[PG_STAT_GET_WAL_COLS] = {0};
 	char		buf[256];
 	PgStat_WalStats *wal_stats;
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(PG_STAT_GET_WAL_COLS);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "wal_records",
@@ -1826,8 +1816,8 @@ pg_stat_get_slru(PG_FUNCTION_ARGS)
 	for (i = 0;; i++)
 	{
 		/* for each row */
-		Datum		values[PG_STAT_GET_SLRU_COLS];
-		bool		nulls[PG_STAT_GET_SLRU_COLS];
+		Datum		values[PG_STAT_GET_SLRU_COLS] = {0};
+		bool		nulls[PG_STAT_GET_SLRU_COLS] = {0};
 		PgStat_SLRUStats stat;
 		const char *name;
 
@@ -1837,8 +1827,6 @@ pg_stat_get_slru(PG_FUNCTION_ARGS)
 			break;
 
 		stat = stats[i];
-		MemSet(values, 0, sizeof(values));
-		MemSet(nulls, 0, sizeof(nulls));
 
 		values[0] = PointerGetDatum(cstring_to_text(name));
 		values[1] = Int64GetDatum(stat.blocks_zeroed);
@@ -2201,14 +2189,10 @@ Datum
 pg_stat_get_archiver(PG_FUNCTION_ARGS)
 {
 	TupleDesc	tupdesc;
-	Datum		values[7];
-	bool		nulls[7];
+	Datum		values[7] = {0};
+	bool		nulls[7] = {0};
 	PgStat_ArchiverStats *archiver_stats;
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(7);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "archived_count",
@@ -2274,15 +2258,11 @@ pg_stat_get_replication_slot(PG_FUNCTION_ARGS)
 	text	   *slotname_text = PG_GETARG_TEXT_P(0);
 	NameData	slotname;
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_GET_REPLICATION_SLOT_COLS];
-	bool		nulls[PG_STAT_GET_REPLICATION_SLOT_COLS];
+	Datum		values[PG_STAT_GET_REPLICATION_SLOT_COLS] = {0};
+	bool		nulls[PG_STAT_GET_REPLICATION_SLOT_COLS] = {0};
 	PgStat_StatReplSlotEntry *slotent;
 	PgStat_StatReplSlotEntry allzero;
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	/* Initialise attributes information in the tuple descriptor */
 	tupdesc = CreateTemplateTupleDesc(PG_STAT_GET_REPLICATION_SLOT_COLS);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "slot_name",
@@ -2348,8 +2328,8 @@ pg_stat_get_subscription_stats(PG_FUNCTION_ARGS)
 #define PG_STAT_GET_SUBSCRIPTION_STATS_COLS	4
 	Oid			subid = PG_GETARG_OID(0);
 	TupleDesc	tupdesc;
-	Datum		values[PG_STAT_GET_SUBSCRIPTION_STATS_COLS];
-	bool		nulls[PG_STAT_GET_SUBSCRIPTION_STATS_COLS];
+	Datum		values[PG_STAT_GET_SUBSCRIPTION_STATS_COLS] = {0};
+	bool		nulls[PG_STAT_GET_SUBSCRIPTION_STATS_COLS] = {0};
 	PgStat_StatSubEntry *subentry;
 	PgStat_StatSubEntry allzero;
 
@@ -2368,10 +2348,6 @@ pg_stat_get_subscription_stats(PG_FUNCTION_ARGS)
 					   TIMESTAMPTZOID, -1, 0);
 	BlessTupleDesc(tupdesc);
 
-	/* Initialise values and NULL flags arrays */
-	MemSet(values, 0, sizeof(values));
-	MemSet(nulls, 0, sizeof(nulls));
-
 	if (!subentry)
 	{
 		/* If the subscription is not found, initialise its stats */