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

contrib/amcheck/verify_nbtree.c

@@ -913,7 +913,7 @@ bt_report_duplicate(BtreeCheckState *state,
 			(errcode(ERRCODE_INDEX_CORRUPTED),
 			 errmsg("index uniqueness is violated for index \"%s\"",
 					RelationGetRelationName(state->rel)),
-			 errdetail("Index %s%s and%s%s (point to heap %s and %s) page lsn=%X/%X.",
+			 errdetail("Index %s%s and%s%s (point to heap %s and %s) page lsn=%X/%08X.",
 					   itid, pposting, nitid, pnposting, htid, nhtid,
 					   LSN_FORMAT_ARGS(state->targetlsn))));
 }
@@ -1058,7 +1058,7 @@ bt_leftmost_ignoring_half_dead(BtreeCheckState *state,
 					(errcode(ERRCODE_NO_DATA),
 					 errmsg_internal("harmless interrupted page deletion detected in index \"%s\"",
 									 RelationGetRelationName(state->rel)),
-					 errdetail_internal("Block=%u right block=%u page lsn=%X/%X.",
+					 errdetail_internal("Block=%u right block=%u page lsn=%X/%08X.",
 										reached, reached_from,
 										LSN_FORMAT_ARGS(pagelsn))));
 
@@ -1283,7 +1283,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("wrong number of high key index tuple attributes in index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Index block=%u natts=%u block type=%s page lsn=%X/%X.",
+					 errdetail_internal("Index block=%u natts=%u block type=%s page lsn=%X/%08X.",
 										state->targetblock,
 										BTreeTupleGetNAtts(itup, state->rel),
 										P_ISLEAF(topaque) ? "heap" : "index",
@@ -1332,7 +1332,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("index tuple size does not equal lp_len in index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Index tid=(%u,%u) tuple size=%zu lp_len=%u page lsn=%X/%X.",
+					 errdetail_internal("Index tid=(%u,%u) tuple size=%zu lp_len=%u page lsn=%X/%08X.",
 										state->targetblock, offset,
 										tupsize, ItemIdGetLength(itemid),
 										LSN_FORMAT_ARGS(state->targetlsn)),
@@ -1356,7 +1356,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("wrong number of index tuple attributes in index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Index tid=%s natts=%u points to %s tid=%s page lsn=%X/%X.",
+					 errdetail_internal("Index tid=%s natts=%u points to %s tid=%s page lsn=%X/%08X.",
 										itid,
 										BTreeTupleGetNAtts(itup, state->rel),
 										P_ISLEAF(topaque) ? "heap" : "index",
@@ -1406,7 +1406,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("could not find tuple using search from root page in index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Index tid=%s points to heap tid=%s page lsn=%X/%X.",
+					 errdetail_internal("Index tid=%s points to heap tid=%s page lsn=%X/%08X.",
 										itid, htid,
 										LSN_FORMAT_ARGS(state->targetlsn))));
 		}
@@ -1435,7 +1435,7 @@ bt_target_page_check(BtreeCheckState *state)
 							(errcode(ERRCODE_INDEX_CORRUPTED),
 							 errmsg_internal("posting list contains misplaced TID in index \"%s\"",
 											 RelationGetRelationName(state->rel)),
-							 errdetail_internal("Index tid=%s posting list offset=%d page lsn=%X/%X.",
+							 errdetail_internal("Index tid=%s posting list offset=%d page lsn=%X/%08X.",
 												itid, i,
 												LSN_FORMAT_ARGS(state->targetlsn))));
 				}
@@ -1488,7 +1488,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("index row size %zu exceeds maximum for index \"%s\"",
 							tupsize, RelationGetRelationName(state->rel)),
-					 errdetail_internal("Index tid=%s points to %s tid=%s page lsn=%X/%X.",
+					 errdetail_internal("Index tid=%s points to %s tid=%s page lsn=%X/%08X.",
 										itid,
 										P_ISLEAF(topaque) ? "heap" : "index",
 										htid,
@@ -1595,7 +1595,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("high key invariant violated for index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Index tid=%s points to %s tid=%s page lsn=%X/%X.",
+					 errdetail_internal("Index tid=%s points to %s tid=%s page lsn=%X/%08X.",
 										itid,
 										P_ISLEAF(topaque) ? "heap" : "index",
 										htid,
@@ -1641,9 +1641,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("item order invariant violated for index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Lower index tid=%s (points to %s tid=%s) "
-										"higher index tid=%s (points to %s tid=%s) "
-										"page lsn=%X/%X.",
+					 errdetail_internal("Lower index tid=%s (points to %s tid=%s) higher index tid=%s (points to %s tid=%s) page lsn=%X/%08X.",
 										itid,
 										P_ISLEAF(topaque) ? "heap" : "index",
 										htid,
@@ -1760,7 +1758,7 @@ bt_target_page_check(BtreeCheckState *state)
 						(errcode(ERRCODE_INDEX_CORRUPTED),
 						 errmsg("cross page item order invariant violated for index \"%s\"",
 								RelationGetRelationName(state->rel)),
-						 errdetail_internal("Last item on page tid=(%u,%u) page lsn=%X/%X.",
+						 errdetail_internal("Last item on page tid=(%u,%u) page lsn=%X/%08X.",
 											state->targetblock, offset,
 											LSN_FORMAT_ARGS(state->targetlsn))));
 			}
@@ -1813,7 +1811,7 @@ bt_target_page_check(BtreeCheckState *state)
 								(errcode(ERRCODE_INDEX_CORRUPTED),
 								 errmsg("right block of leaf block is non-leaf for index \"%s\"",
 										RelationGetRelationName(state->rel)),
-								 errdetail_internal("Block=%u page lsn=%X/%X.",
+								 errdetail_internal("Block=%u page lsn=%X/%08X.",
 													state->targetblock,
 													LSN_FORMAT_ARGS(state->targetlsn))));
 
@@ -2237,7 +2235,7 @@ bt_child_highkey_check(BtreeCheckState *state,
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("the first child of leftmost target page is not leftmost of its level in index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%X.",
+					 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%08X.",
 										state->targetblock, blkno,
 										LSN_FORMAT_ARGS(state->targetlsn))));
 
@@ -2323,7 +2321,7 @@ bt_child_highkey_check(BtreeCheckState *state,
 								(errcode(ERRCODE_INDEX_CORRUPTED),
 								 errmsg("child high key is greater than rightmost pivot key on target level in index \"%s\"",
 										RelationGetRelationName(state->rel)),
-								 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%X.",
+								 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%08X.",
 													state->targetblock, blkno,
 													LSN_FORMAT_ARGS(state->targetlsn))));
 					pivotkey_offset = P_HIKEY;
@@ -2353,7 +2351,7 @@ bt_child_highkey_check(BtreeCheckState *state,
 							(errcode(ERRCODE_INDEX_CORRUPTED),
 							 errmsg("can't find left sibling high key in index \"%s\"",
 									RelationGetRelationName(state->rel)),
-							 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%X.",
+							 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%08X.",
 												state->targetblock, blkno,
 												LSN_FORMAT_ARGS(state->targetlsn))));
 				itup = state->lowkey;
@@ -2365,7 +2363,7 @@ bt_child_highkey_check(BtreeCheckState *state,
 						(errcode(ERRCODE_INDEX_CORRUPTED),
 						 errmsg("mismatch between parent key and child high key in index \"%s\"",
 								RelationGetRelationName(state->rel)),
-						 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%X.",
+						 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%08X.",
 											state->targetblock, blkno,
 											LSN_FORMAT_ARGS(state->targetlsn))));
 			}
@@ -2505,7 +2503,7 @@ bt_child_check(BtreeCheckState *state, BTScanInsert targetkey,
 				(errcode(ERRCODE_INDEX_CORRUPTED),
 				 errmsg("downlink to deleted page found in index \"%s\"",
 						RelationGetRelationName(state->rel)),
-				 errdetail_internal("Parent block=%u child block=%u parent page lsn=%X/%X.",
+				 errdetail_internal("Parent block=%u child block=%u parent page lsn=%X/%08X.",
 									state->targetblock, childblock,
 									LSN_FORMAT_ARGS(state->targetlsn))));
 
@@ -2546,7 +2544,7 @@ bt_child_check(BtreeCheckState *state, BTScanInsert targetkey,
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("down-link lower bound invariant violated for index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Parent block=%u child index tid=(%u,%u) parent page lsn=%X/%X.",
+					 errdetail_internal("Parent block=%u child index tid=(%u,%u) parent page lsn=%X/%08X.",
 										state->targetblock, childblock, offset,
 										LSN_FORMAT_ARGS(state->targetlsn))));
 	}
@@ -2616,7 +2614,7 @@ bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit,
 				(errcode(ERRCODE_NO_DATA),
 				 errmsg_internal("harmless interrupted page split detected in index \"%s\"",
 								 RelationGetRelationName(state->rel)),
-				 errdetail_internal("Block=%u level=%u left sibling=%u page lsn=%X/%X.",
+				 errdetail_internal("Block=%u level=%u left sibling=%u page lsn=%X/%08X.",
 									blkno, opaque->btpo_level,
 									opaque->btpo_prev,
 									LSN_FORMAT_ARGS(pagelsn))));
@@ -2638,7 +2636,7 @@ bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit,
 				(errcode(ERRCODE_INDEX_CORRUPTED),
 				 errmsg("leaf index block lacks downlink in index \"%s\"",
 						RelationGetRelationName(state->rel)),
-				 errdetail_internal("Block=%u page lsn=%X/%X.",
+				 errdetail_internal("Block=%u page lsn=%X/%08X.",
 									blkno,
 									LSN_FORMAT_ARGS(pagelsn))));
 
@@ -2704,7 +2702,7 @@ bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit,
 				(errcode(ERRCODE_INDEX_CORRUPTED),
 				 errmsg_internal("downlink to deleted leaf page found in index \"%s\"",
 								 RelationGetRelationName(state->rel)),
-				 errdetail_internal("Top parent/target block=%u leaf block=%u top parent/under check lsn=%X/%X.",
+				 errdetail_internal("Top parent/target block=%u leaf block=%u top parent/under check lsn=%X/%08X.",
 									blkno, childblk,
 									LSN_FORMAT_ARGS(pagelsn))));
 
@@ -2730,7 +2728,7 @@ bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit,
 			(errcode(ERRCODE_INDEX_CORRUPTED),
 			 errmsg("internal index block lacks downlink in index \"%s\"",
 					RelationGetRelationName(state->rel)),
-			 errdetail_internal("Block=%u level=%u page lsn=%X/%X.",
+			 errdetail_internal("Block=%u level=%u page lsn=%X/%08X.",
 								blkno, opaque->btpo_level,
 								LSN_FORMAT_ARGS(pagelsn))));
 }

contrib/pageinspect/expected/gist.out

@@ -5,21 +5,21 @@ CREATE UNLOGGED TABLE test_gist AS SELECT point(i,i) p, i::text t FROM
 CREATE INDEX test_gist_idx ON test_gist USING gist (p);
 -- Page 0 is the root, the rest are leaf pages
 SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 0));
- lsn | nsn | rightlink  | flags 
------+-----+------------+-------
- 0/1 | 0/0 | 4294967295 | {}
+    lsn     |    nsn     | rightlink  | flags 
+------------+------------+------------+-------
+ 0/00000001 | 0/00000000 | 4294967295 | {}
 (1 row)
 
 SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 1));
- lsn | nsn | rightlink  | flags  
------+-----+------------+--------
- 0/1 | 0/0 | 4294967295 | {leaf}
+    lsn     |    nsn     | rightlink  | flags  
+------------+------------+------------+--------
+ 0/00000001 | 0/00000000 | 4294967295 | {leaf}
 (1 row)
 
 SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 2));
- lsn | nsn | rightlink | flags  
------+-----+-----------+--------
- 0/1 | 0/0 |         1 | {leaf}
+    lsn     |    nsn     | rightlink | flags  
+------------+------------+-----------+--------
+ 0/00000001 | 0/00000000 |         1 | {leaf}
 (1 row)
 
 SELECT * FROM gist_page_items(get_raw_page('test_gist_idx', 0), 'test_gist_idx');

contrib/pageinspect/expected/page.out

@@ -265,9 +265,9 @@ SELECT fsm_page_contents(decode(repeat('00', :block_size), 'hex'));
 (1 row)
 
 SELECT page_header(decode(repeat('00', :block_size), 'hex'));
-      page_header      
------------------------
- (0/0,0,0,0,0,0,0,0,0)
+         page_header          
+------------------------------
+ (0/00000000,0,0,0,0,0,0,0,0)
 (1 row)
 
 SELECT page_checksum(decode(repeat('00', :block_size), 'hex'), 1);

contrib/pageinspect/rawpage.c

@@ -282,7 +282,7 @@ page_header(PG_FUNCTION_ARGS)
 	{
 		char		lsnchar[64];
 
-		snprintf(lsnchar, sizeof(lsnchar), "%X/%X", LSN_FORMAT_ARGS(lsn));
+		snprintf(lsnchar, sizeof(lsnchar), "%X/%08X", LSN_FORMAT_ARGS(lsn));
 		values[0] = CStringGetTextDatum(lsnchar);
 	}
 	else

contrib/pg_walinspect/expected/pg_walinspect.out

@@ -19,14 +19,14 @@ INSERT INTO sample_tbl SELECT * FROM generate_series(3, 4);
 -- ===================================================================
 -- Invalid input LSN.
 SELECT * FROM pg_get_wal_record_info('0/0');
-ERROR:  could not read WAL at LSN 0/0
+ERROR:  could not read WAL at LSN 0/00000000
 -- Invalid start LSN.
 SELECT * FROM pg_get_wal_records_info('0/0', :'wal_lsn1');
-ERROR:  could not read WAL at LSN 0/0
+ERROR:  could not read WAL at LSN 0/00000000
 SELECT * FROM pg_get_wal_stats('0/0', :'wal_lsn1');
-ERROR:  could not read WAL at LSN 0/0
+ERROR:  could not read WAL at LSN 0/00000000
 SELECT * FROM pg_get_wal_block_info('0/0', :'wal_lsn1');
-ERROR:  could not read WAL at LSN 0/0
+ERROR:  could not read WAL at LSN 0/00000000
 -- Start LSN > End LSN.
 SELECT * FROM pg_get_wal_records_info(:'wal_lsn2', :'wal_lsn1');
 ERROR:  WAL start LSN must be less than end LSN

contrib/pg_walinspect/pg_walinspect.c

@@ -105,7 +105,7 @@ InitXLogReaderState(XLogRecPtr lsn)
 	if (lsn < XLOG_BLCKSZ)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("could not read WAL at LSN %X/%X",
+				 errmsg("could not read WAL at LSN %X/%08X",
 						LSN_FORMAT_ARGS(lsn))));
 
 	private_data = (ReadLocalXLogPageNoWaitPrivate *)
@@ -128,8 +128,8 @@ InitXLogReaderState(XLogRecPtr lsn)
 
 	if (XLogRecPtrIsInvalid(first_valid_record))
 		ereport(ERROR,
-				(errmsg("could not find a valid record after %X/%X",
-						LSN_FORMAT_ARGS(lsn))));
+				errmsg("could not find a valid record after %X/%08X",
+					   LSN_FORMAT_ARGS(lsn)));
 
 	return xlogreader;
 }
@@ -168,12 +168,12 @@ ReadNextXLogRecord(XLogReaderState *xlogreader)
 		if (errormsg)
 			ereport(ERROR,
 					(errcode_for_file_access(),
-					 errmsg("could not read WAL at %X/%X: %s",
+					 errmsg("could not read WAL at %X/%08X: %s",
 							LSN_FORMAT_ARGS(xlogreader->EndRecPtr), errormsg)));
 		else
 			ereport(ERROR,
 					(errcode_for_file_access(),
-					 errmsg("could not read WAL at %X/%X",
+					 errmsg("could not read WAL at %X/%08X",
 							LSN_FORMAT_ARGS(xlogreader->EndRecPtr))));
 	}
 
@@ -479,7 +479,7 @@ pg_get_wal_record_info(PG_FUNCTION_ARGS)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("WAL input LSN must be less than current LSN"),
-				 errdetail("Current WAL LSN on the database system is at %X/%X.",
+				 errdetail("Current WAL LSN on the database system is at %X/%08X.",
 						   LSN_FORMAT_ARGS(curr_lsn))));
 
 	/* Build a tuple descriptor for our result type. */
@@ -491,7 +491,7 @@ pg_get_wal_record_info(PG_FUNCTION_ARGS)
 	if (!ReadNextXLogRecord(xlogreader))
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("could not read WAL at %X/%X",
+				 errmsg("could not read WAL at %X/%08X",
 						LSN_FORMAT_ARGS(xlogreader->EndRecPtr))));
 
 	GetWALRecordInfo(xlogreader, values, nulls, PG_GET_WAL_RECORD_INFO_COLS);
@@ -521,7 +521,7 @@ ValidateInputLSNs(XLogRecPtr start_lsn, XLogRecPtr *end_lsn)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("WAL start LSN must be less than current LSN"),
-				 errdetail("Current WAL LSN on the database system is at %X/%X.",
+				 errdetail("Current WAL LSN on the database system is at %X/%08X.",
 						   LSN_FORMAT_ARGS(curr_lsn))));
 
 	if (start_lsn > *end_lsn)
@@ -827,7 +827,7 @@ pg_get_wal_records_info_till_end_of_wal(PG_FUNCTION_ARGS)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("WAL start LSN must be less than current LSN"),
-				 errdetail("Current WAL LSN on the database system is at %X/%X.",
+				 errdetail("Current WAL LSN on the database system is at %X/%08X.",
 						   LSN_FORMAT_ARGS(end_lsn))));
 
 	GetWALRecordsInfo(fcinfo, start_lsn, end_lsn);
@@ -846,7 +846,7 @@ pg_get_wal_stats_till_end_of_wal(PG_FUNCTION_ARGS)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("WAL start LSN must be less than current LSN"),
-				 errdetail("Current WAL LSN on the database system is at %X/%X.",
+				 errdetail("Current WAL LSN on the database system is at %X/%08X.",
 						   LSN_FORMAT_ARGS(end_lsn))));
 
 	GetWalStats(fcinfo, start_lsn, end_lsn, stats_per_record);