public inbox for [email protected]  

help / color / mirror / Atom feed

From: Hayato Kuroda (Fujitsu) <[email protected]>
To: 'Michael Paquier' <[email protected]>
Cc: '[email protected]' <[email protected]>
Subject: RE: ReplicationSlotRelease() crashes when the instance is in the single user mode
Date: Thu, 20 Feb 2025 02:22:41 +0000
Message-ID: <OSCPR01MB14966FCE16ECCF29AE0502AF2F5C42@OSCPR01MB14966.jpnprd01.prod.outlook.com> (raw)
In-Reply-To: <[email protected]>
References: <OSCPR01MB14966ED588A0328DAEBE8CB25F5FA2@OSCPR01MB14966.jpnprd01.prod.outlook.com>
	<[email protected]>
	<OSCPR01MB149669EF7D087A588773B7E04F5FA2@OSCPR01MB14966.jpnprd01.prod.outlook.com>
	<[email protected]>
	<OSCPR01MB14966559522B9699E1F769128F5FA2@OSCPR01MB14966.jpnprd01.prod.outlook.com>
	<OSCPR01MB14966F234CD3121F51810D5CCF5C52@OSCPR01MB14966.jpnprd01.prod.outlook.com>
	<[email protected]>

Dear Michael,

> I did not check how these call behave individually, just a few
> comments while putting my eyes on the patch.
> 
> +	if (!IsUnderPostmaster)
> +		elog(ERROR,
> +			 "slot operation is prohibited in the single user mode");
> 
> elog() should not be used for failures that can be user-facing as this
> would not provide any translation.

I intentionally used elog() because I thought single user mode is not user-facing.
But it is OK for me to use ereport() instead.

> I'd suggest rewording the error message to provide some more context,
> as well, say:
> "cannot use %s in single-user mode", "function_name"

Fixed. PSA new version

Best regards,
Hayato Kuroda
FUJITSU LIMITED



Attachments:

  [application/octet-stream] v2-0001-Prohibit-slot-operations-while-in-the-single-user.patch (2.8K, ../OSCPR01MB14966FCE16ECCF29AE0502AF2F5C42@OSCPR01MB14966.jpnprd01.prod.outlook.com/2-v2-0001-Prohibit-slot-operations-while-in-the-single-user.patch)
  download | inline diff:
From 7fe5c8a1854747ce3e14cb9ab0a5a3dc730ae166 Mon Sep 17 00:00:00 2001
From: Hayato Kuroda <[email protected]>
Date: Wed, 19 Feb 2025 11:37:26 +0900
Subject: [PATCH v2] Prohibit slot operations while in the single user mode

---
 src/backend/replication/slotfuncs.c | 31 +++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/src/backend/replication/slotfuncs.c b/src/backend/replication/slotfuncs.c
index f652ec8a73..70c01db891 100644
--- a/src/backend/replication/slotfuncs.c
+++ b/src/backend/replication/slotfuncs.c
@@ -17,6 +17,7 @@
 #include "access/xlogrecovery.h"
 #include "access/xlogutils.h"
 #include "funcapi.h"
+#include "miscadmin.h"
 #include "replication/logical.h"
 #include "replication/slot.h"
 #include "replication/slotsync.h"
@@ -73,6 +74,12 @@ pg_create_physical_replication_slot(PG_FUNCTION_ARGS)
 	HeapTuple	tuple;
 	Datum		result;
 
+	if (!IsUnderPostmaster)
+		ereport(ERROR,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("cannot use %s in single-user mode",
+						"pg_create_physical_replication_slot")));
+
 	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
 		elog(ERROR, "return type must be a row type");
 
@@ -179,6 +186,12 @@ pg_create_logical_replication_slot(PG_FUNCTION_ARGS)
 	Datum		values[2];
 	bool		nulls[2];
 
+	if (!IsUnderPostmaster)
+		ereport(ERROR,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("cannot use %s in single-user mode",
+						"pg_create_logical_replication_slot")));
+
 	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
 		elog(ERROR, "return type must be a row type");
 
@@ -515,6 +528,12 @@ pg_replication_slot_advance(PG_FUNCTION_ARGS)
 
 	Assert(!MyReplicationSlot);
 
+	if (!IsUnderPostmaster)
+		ereport(ERROR,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("cannot use %s in single-user mode",
+						"pg_replication_slot_advance")));
+
 	CheckSlotPermissions();
 
 	if (XLogRecPtrIsInvalid(moveto))
@@ -612,6 +631,12 @@ copy_replication_slot(FunctionCallInfo fcinfo, bool logical_slot)
 	TupleDesc	tupdesc;
 	HeapTuple	tuple;
 
+	if (!IsUnderPostmaster)
+		ereport(ERROR,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("cannot use %s in single-user mode",
+						"pg_copy_replication_slot")));
+
 	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
 		elog(ERROR, "return type must be a row type");
 
@@ -866,6 +891,12 @@ pg_sync_replication_slots(PG_FUNCTION_ARGS)
 	char	   *err;
 	StringInfoData app_name;
 
+	if (!IsUnderPostmaster)
+		ereport(ERROR,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("cannot use %s in single-user mode",
+						"pg_sync_replication_slots")));
+
 	CheckSlotPermissions();
 
 	if (!RecoveryInProgress())
-- 
2.43.5

view thread (31+ messages)  latest in thread

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: [email protected]
  Cc: [email protected], [email protected], [email protected]
  Subject: RE: ReplicationSlotRelease() crashes when the instance is in the single user mode
  In-Reply-To: <OSCPR01MB14966FCE16ECCF29AE0502AF2F5C42@OSCPR01MB14966.jpnprd01.prod.outlook.com>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox