Standardize LSN formatting by zero padding

This commit standardizes the output format for LSNs to ensure consistent
representation across various tools and messages.  Previously, LSNs were
inconsistently printed as `%X/%X` in some contexts, while others used
zero-padding.  This often led to confusion when comparing.

To address this, the LSN format is now uniformly set to `%X/%08X`,
ensuring the lower 32-bit part is always zero-padded to eight
hexadecimal digits.

Author: Japin Li <japinli@hotmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/ME0P300MB0445CA53CA0E4B8C1879AF84B641A@ME0P300MB0445.AUSP300.PROD.OUTLOOK.COM

3 files changed, 9 insertions, 9 deletions

diff --git a/src/backend/backup/backup_manifest.c b/src/backend/backup/backup_manifest.c
index 22e2be37c95..d05252f383c 100644
--- a/src/backend/backup/backup_manifest.c
+++ b/src/backend/backup/backup_manifest.c
@@ -281,7 +281,7 @@ AddWALInfoToBackupManifest(backup_manifest_info *manifest, XLogRecPtr startptr,
 		}
 
 		AppendToManifest(manifest,
-						 "%s{ \"Timeline\": %u, \"Start-LSN\": \"%X/%X\", \"End-LSN\": \"%X/%X\" }",
+						 "%s{ \"Timeline\": %u, \"Start-LSN\": \"%X/%08X\", \"End-LSN\": \"%X/%08X\" }",
 						 first_wal_range ? "" : ",\n",
 						 entry->tli,
 						 LSN_FORMAT_ARGS(tl_beginptr),
diff --git a/src/backend/backup/basebackup_copy.c b/src/backend/backup/basebackup_copy.c
index a284ce318ff..18b0b5a52d3 100644
--- a/src/backend/backup/basebackup_copy.c
+++ b/src/backend/backup/basebackup_copy.c
@@ -361,7 +361,7 @@ SendXlogRecPtrResult(XLogRecPtr ptr, TimeLineID tli)
 	tstate = begin_tup_output_tupdesc(dest, tupdesc, &TTSOpsVirtual);
 
 	/* Data row */
-	values[0] = CStringGetTextDatum(psprintf("%X/%X", LSN_FORMAT_ARGS(ptr)));
+	values[0] = CStringGetTextDatum(psprintf("%X/%08X", LSN_FORMAT_ARGS(ptr)));
 	values[1] = Int64GetDatum(tli);
 	do_tup_output(tstate, values, nulls);
 
diff --git a/src/backend/backup/basebackup_incremental.c b/src/backend/backup/basebackup_incremental.c
index 28491b1e0ab..a0d48ff0fef 100644
--- a/src/backend/backup/basebackup_incremental.c
+++ b/src/backend/backup/basebackup_incremental.c
@@ -409,7 +409,7 @@ PrepareForIncrementalBackup(IncrementalBackupInfo *ib,
 			if (range->start_lsn < tlep[i]->begin)
 				ereport(ERROR,
 						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-						 errmsg("manifest requires WAL from initial timeline %u starting at %X/%X, but that timeline begins at %X/%X",
+						 errmsg("manifest requires WAL from initial timeline %u starting at %X/%08X, but that timeline begins at %X/%08X",
 								range->tli,
 								LSN_FORMAT_ARGS(range->start_lsn),
 								LSN_FORMAT_ARGS(tlep[i]->begin))));
@@ -419,7 +419,7 @@ PrepareForIncrementalBackup(IncrementalBackupInfo *ib,
 			if (range->start_lsn != tlep[i]->begin)
 				ereport(ERROR,
 						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-						 errmsg("manifest requires WAL from continuation timeline %u starting at %X/%X, but that timeline begins at %X/%X",
+						 errmsg("manifest requires WAL from continuation timeline %u starting at %X/%08X, but that timeline begins at %X/%08X",
 								range->tli,
 								LSN_FORMAT_ARGS(range->start_lsn),
 								LSN_FORMAT_ARGS(tlep[i]->begin))));
@@ -430,7 +430,7 @@ PrepareForIncrementalBackup(IncrementalBackupInfo *ib,
 			if (range->end_lsn > backup_state->startpoint)
 				ereport(ERROR,
 						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-						 errmsg("manifest requires WAL from final timeline %u ending at %X/%X, but this backup starts at %X/%X",
+						 errmsg("manifest requires WAL from final timeline %u ending at %X/%08X, but this backup starts at %X/%08X",
 								range->tli,
 								LSN_FORMAT_ARGS(range->end_lsn),
 								LSN_FORMAT_ARGS(backup_state->startpoint)),
@@ -441,7 +441,7 @@ PrepareForIncrementalBackup(IncrementalBackupInfo *ib,
 			if (range->end_lsn != tlep[i]->end)
 				ereport(ERROR,
 						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-						 errmsg("manifest requires WAL from non-final timeline %u ending at %X/%X, but this server switched timelines at %X/%X",
+						 errmsg("manifest requires WAL from non-final timeline %u ending at %X/%08X, but this server switched timelines at %X/%08X",
 								range->tli,
 								LSN_FORMAT_ARGS(range->end_lsn),
 								LSN_FORMAT_ARGS(tlep[i]->end))));
@@ -522,18 +522,18 @@ PrepareForIncrementalBackup(IncrementalBackupInfo *ib,
 			if (XLogRecPtrIsInvalid(tli_missing_lsn))
 				ereport(ERROR,
 						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-						 errmsg("WAL summaries are required on timeline %u from %X/%X to %X/%X, but no summaries for that timeline and LSN range exist",
+						 errmsg("WAL summaries are required on timeline %u from %X/%08X to %X/%08X, but no summaries for that timeline and LSN range exist",
 								tle->tli,
 								LSN_FORMAT_ARGS(tli_start_lsn),
 								LSN_FORMAT_ARGS(tli_end_lsn))));
 			else
 				ereport(ERROR,
 						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-						 errmsg("WAL summaries are required on timeline %u from %X/%X to %X/%X, but the summaries for that timeline and LSN range are incomplete",
+						 errmsg("WAL summaries are required on timeline %u from %X/%08X to %X/%08X, but the summaries for that timeline and LSN range are incomplete",
 								tle->tli,
 								LSN_FORMAT_ARGS(tli_start_lsn),
 								LSN_FORMAT_ARGS(tli_end_lsn)),
-						 errdetail("The first unsummarized LSN in this range is %X/%X.",
+						 errdetail("The first unsummarized LSN in this range is %X/%08X.",
 								   LSN_FORMAT_ARGS(tli_missing_lsn))));
 		}