Use NameData datatype for slotname in stats.

This will make it consistent with the other usage of slotname in the code.
In the passing, change pgstat_report_replslot signature to use a structure
rather than multiple parameters.

Reported-by: Andres Freund
Author: Vignesh C
Reviewed-by: Sawada Masahiko, Amit Kapila
Discussion: https://postgr.es/m/20210319185247.ldebgpdaxsowiflw@alap3.anarazel.de

src/backend/postmaster/pgstat.c

@@ -64,6 +64,7 @@
 #include "storage/pg_shmem.h"
 #include "storage/proc.h"
 #include "storage/procsignal.h"
+#include "utils/builtins.h"
 #include "utils/guc.h"
 #include "utils/memutils.h"
 #include "utils/ps_status.h"
@@ -1539,7 +1540,7 @@ pgstat_reset_replslot_counter(const char *name)
 		if (SlotIsPhysical(slot))
 			return;
 
-		strlcpy(msg.m_slotname, name, NAMEDATALEN);
+		namestrcpy(&msg.m_slotname, name);
 		msg.clearall = false;
 	}
 	else
@@ -1812,10 +1813,7 @@ pgstat_report_tempfile(size_t filesize)
  * ----------
  */
 void
-pgstat_report_replslot(const char *slotname, PgStat_Counter spilltxns,
-					   PgStat_Counter spillcount, PgStat_Counter spillbytes,
-					   PgStat_Counter streamtxns, PgStat_Counter streamcount,
-					   PgStat_Counter streambytes)
+pgstat_report_replslot(const PgStat_ReplSlotStats *repSlotStat)
 {
 	PgStat_MsgReplSlot msg;
 
@@ -1823,14 +1821,14 @@ pgstat_report_replslot(const char *slotname, PgStat_Counter spilltxns,
 	 * Prepare and send the message
 	 */
 	pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_REPLSLOT);
-	strlcpy(msg.m_slotname, slotname, NAMEDATALEN);
+	namestrcpy(&msg.m_slotname, NameStr(repSlotStat->slotname));
 	msg.m_drop = false;
-	msg.m_spill_txns = spilltxns;
-	msg.m_spill_count = spillcount;
-	msg.m_spill_bytes = spillbytes;
-	msg.m_stream_txns = streamtxns;
-	msg.m_stream_count = streamcount;
-	msg.m_stream_bytes = streambytes;
+	msg.m_spill_txns = repSlotStat->spill_txns;
+	msg.m_spill_count = repSlotStat->spill_count;
+	msg.m_spill_bytes = repSlotStat->spill_bytes;
+	msg.m_stream_txns = repSlotStat->stream_txns;
+	msg.m_stream_count = repSlotStat->stream_count;
+	msg.m_stream_bytes = repSlotStat->stream_bytes;
 	pgstat_send(&msg, sizeof(PgStat_MsgReplSlot));
 }
 
@@ -1846,7 +1844,7 @@ pgstat_report_replslot_drop(const char *slotname)
 	PgStat_MsgReplSlot msg;
 
 	pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_REPLSLOT);
-	strlcpy(msg.m_slotname, slotname, NAMEDATALEN);
+	namestrcpy(&msg.m_slotname, slotname);
 	msg.m_drop = true;
 	pgstat_send(&msg, sizeof(PgStat_MsgReplSlot));
 }
@@ -5202,7 +5200,7 @@ pgstat_recv_resetreplslotcounter(PgStat_MsgResetreplslotcounter *msg,
 	else
 	{
 		/* Get the index of replication slot statistics to reset */
-		idx = pgstat_replslot_index(msg->m_slotname, false);
+		idx = pgstat_replslot_index(NameStr(msg->m_slotname), false);
 
 		/*
 		 * Nothing to do if the given slot entry is not found.  This could
@@ -5538,7 +5536,7 @@ pgstat_recv_replslot(PgStat_MsgReplSlot *msg, int len)
 	 * Get the index of replication slot statistics.  On dropping, we don't
 	 * create the new statistics.
 	 */
-	idx = pgstat_replslot_index(msg->m_slotname, !msg->m_drop);
+	idx = pgstat_replslot_index(NameStr(msg->m_slotname), !msg->m_drop);
 
 	/*
 	 * The slot entry is not found or there is no space to accommodate the new
@@ -5763,7 +5761,7 @@ pgstat_replslot_index(const char *name, bool create_it)
 	Assert(nReplSlotStats <= max_replication_slots);
 	for (i = 0; i < nReplSlotStats; i++)
 	{
-		if (strcmp(replSlotStats[i].slotname, name) == 0)
+		if (namestrcmp(&replSlotStats[i].slotname, name) == 0)
 			return i;			/* found */
 	}
 
@@ -5776,7 +5774,7 @@ pgstat_replslot_index(const char *name, bool create_it)
 
 	/* Register new slot */
 	memset(&replSlotStats[nReplSlotStats], 0, sizeof(PgStat_ReplSlotStats));
-	strlcpy(replSlotStats[nReplSlotStats].slotname, name, NAMEDATALEN);
+	namestrcpy(&replSlotStats[nReplSlotStats].slotname, name);
 
 	return nReplSlotStats++;
 }

src/backend/replication/logical/logical.c

@@ -1773,6 +1773,7 @@ void
 UpdateDecodingStats(LogicalDecodingContext *ctx)
 {
 	ReorderBuffer *rb = ctx->reorder;
+	PgStat_ReplSlotStats repSlotStat;
 
 	/*
 	 * Nothing to do if we haven't spilled or streamed anything since the last
@@ -1790,9 +1791,15 @@ UpdateDecodingStats(LogicalDecodingContext *ctx)
 		 (long long) rb->streamCount,
 		 (long long) rb->streamBytes);
 
-	pgstat_report_replslot(NameStr(ctx->slot->data.name),
-						   rb->spillTxns, rb->spillCount, rb->spillBytes,
-						   rb->streamTxns, rb->streamCount, rb->streamBytes);
+	namestrcpy(&repSlotStat.slotname, NameStr(ctx->slot->data.name));
+	repSlotStat.spill_txns = rb->spillTxns;
+	repSlotStat.spill_count = rb->spillCount;
+	repSlotStat.spill_bytes = rb->spillBytes;
+	repSlotStat.stream_txns = rb->streamTxns;
+	repSlotStat.stream_count = rb->streamCount;
+	repSlotStat.stream_bytes = rb->streamBytes;
+
+	pgstat_report_replslot(&repSlotStat);
 	rb->spillTxns = 0;
 	rb->spillCount = 0;
 	rb->spillBytes = 0;

src/backend/replication/slot.c

@@ -328,7 +328,12 @@ ReplicationSlotCreate(const char *name, bool db_specific,
 	 * ReplicationSlotAllocationLock.
 	 */
 	if (SlotIsLogical(slot))
-		pgstat_report_replslot(NameStr(slot->data.name), 0, 0, 0, 0, 0, 0);
+	{
+		PgStat_ReplSlotStats repSlotStat;
+		MemSet(&repSlotStat, 0, sizeof(PgStat_ReplSlotStats));
+		namestrcpy(&repSlotStat.slotname, NameStr(slot->data.name));
+		pgstat_report_replslot(&repSlotStat);
+	}
 
 	/*
 	 * Now that the slot has been marked as in_use and active, it's safe to

src/backend/utils/adt/pgstatfuncs.c

@@ -2328,7 +2328,7 @@ pg_stat_get_replication_slots(PG_FUNCTION_ARGS)
 		MemSet(values, 0, sizeof(values));
 		MemSet(nulls, 0, sizeof(nulls));
 
-		values[0] = PointerGetDatum(cstring_to_text(s->slotname));
+		values[0] = CStringGetTextDatum(NameStr(s->slotname));
 		values[1] = Int64GetDatum(s->spill_txns);
 		values[2] = Int64GetDatum(s->spill_count);
 		values[3] = Int64GetDatum(s->spill_bytes);

src/include/pgstat.h

@@ -393,7 +393,7 @@ typedef struct PgStat_MsgResetslrucounter
 typedef struct PgStat_MsgResetreplslotcounter
 {
 	PgStat_MsgHdr m_hdr;
-	char		m_slotname[NAMEDATALEN];
+	NameData      m_slotname;
 	bool		clearall;
 } PgStat_MsgResetreplslotcounter;
 
@@ -540,7 +540,7 @@ typedef struct PgStat_MsgSLRU
 typedef struct PgStat_MsgReplSlot
 {
 	PgStat_MsgHdr m_hdr;
-	char		m_slotname[NAMEDATALEN];
+	NameData	m_slotname;
 	bool		m_drop;
 	PgStat_Counter m_spill_txns;
 	PgStat_Counter m_spill_count;
@@ -917,7 +917,7 @@ typedef struct PgStat_SLRUStats
  */
 typedef struct PgStat_ReplSlotStats
 {
-	char		slotname[NAMEDATALEN];
+	NameData	slotname;
 	PgStat_Counter spill_txns;
 	PgStat_Counter spill_count;
 	PgStat_Counter spill_bytes;
@@ -1027,10 +1027,7 @@ extern void pgstat_report_recovery_conflict(int reason);
 extern void pgstat_report_deadlock(void);
 extern void pgstat_report_checksum_failures_in_db(Oid dboid, int failurecount);
 extern void pgstat_report_checksum_failure(void);
-extern void pgstat_report_replslot(const char *slotname, PgStat_Counter spilltxns,
-								   PgStat_Counter spillcount, PgStat_Counter spillbytes,
-								   PgStat_Counter streamtxns, PgStat_Counter streamcount,
-								   PgStat_Counter streambytes);
+extern void pgstat_report_replslot(const PgStat_ReplSlotStats *repSlotStat);
 extern void pgstat_report_replslot_drop(const char *slotname);
 
 extern void pgstat_initialize(void);