Rename cluster.c to repack.c (and corresponding .h)

CLUSTER is no longer the favored way to invoke this functionality, and
the code is about to shift its focus to the REPACK more ambitiously.
Rename the file to avoid leaving an unnecessary historical artifact
around.

Author: Álvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/202603271635.owyhm7btgoic@alvherre.pgsql

src/backend/commands/Makefile

@@ -18,7 +18,6 @@ OBJS = \
 	amcmds.o \
 	analyze.o \
 	async.o \
-	cluster.o \
 	collationcmds.o \
 	comment.o \
 	constraint.o \
@@ -51,6 +50,7 @@ OBJS = \
 	proclang.o \
 	propgraphcmds.o \
 	publicationcmds.o \
+	repack.o \
 	schemacmds.o \
 	seclabel.o \
 	sequence.o \

src/backend/commands/matview.c

@@ -24,8 +24,8 @@
 #include "catalog/namespace.h"
 #include "catalog/pg_am.h"
 #include "catalog/pg_opclass.h"
-#include "commands/cluster.h"
 #include "commands/matview.h"
+#include "commands/repack.h"
 #include "commands/tablecmds.h"
 #include "commands/tablespace.h"
 #include "executor/executor.h"

src/backend/commands/meson.build

@@ -6,7 +6,6 @@ backend_sources += files(
   'amcmds.c',
   'analyze.c',
   'async.c',
-  'cluster.c',
   'collationcmds.c',
   'comment.c',
   'constraint.c',
@@ -39,6 +38,7 @@ backend_sources += files(
   'proclang.c',
   'propgraphcmds.c',
   'publicationcmds.c',
+  'repack.c',
   'schemacmds.c',
   'seclabel.c',
   'sequence.c',

src/backend/commands/repack.c

@@ -1,6 +1,6 @@
 /*-------------------------------------------------------------------------
  *
- * cluster.c
+ * repack.c
  *    REPACK a table; formerly known as CLUSTER.  VACUUM FULL also uses
  *    parts of this code.
  *
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  src/backend/commands/cluster.c
+ *	  src/backend/commands/repack.c
  *
  *-------------------------------------------------------------------------
  */
@@ -33,9 +33,9 @@
 #include "catalog/pg_am.h"
 #include "catalog/pg_inherits.h"
 #include "catalog/toasting.h"
-#include "commands/cluster.h"
 #include "commands/defrem.h"
 #include "commands/progress.h"
+#include "commands/repack.h"
 #include "commands/tablecmds.h"
 #include "commands/vacuum.h"
 #include "miscadmin.h"

src/backend/commands/tablecmds.c

@@ -57,10 +57,10 @@
 #include "catalog/storage.h"
 #include "catalog/storage_xlog.h"
 #include "catalog/toasting.h"
-#include "commands/cluster.h"
 #include "commands/comment.h"
 #include "commands/defrem.h"
 #include "commands/event_trigger.h"
+#include "commands/repack.h"
 #include "commands/sequence.h"
 #include "commands/tablecmds.h"
 #include "commands/tablespace.h"

src/backend/commands/vacuum.c

@@ -9,7 +9,7 @@
  *
  * VACUUM for heap AM is implemented in vacuumlazy.c, parallel vacuum in
  * vacuumparallel.c, ANALYZE in analyze.c, and VACUUM FULL is a variant of
- * CLUSTER, handled in cluster.c.
+ * REPACK, handled in repack.c.
  *
  *
  * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
@@ -38,9 +38,9 @@
 #include "catalog/pg_database.h"
 #include "catalog/pg_inherits.h"
 #include "commands/async.h"
-#include "commands/cluster.h"
 #include "commands/defrem.h"
 #include "commands/progress.h"
+#include "commands/repack.h"
 #include "commands/vacuum.h"
 #include "miscadmin.h"
 #include "nodes/makefuncs.h"
@@ -2293,7 +2293,7 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 			if ((params.options & VACOPT_VERBOSE) != 0)
 				cluster_params.options |= CLUOPT_VERBOSE;
 
-			/* VACUUM FULL is a variant of REPACK; see cluster.c */
+			/* VACUUM FULL is a variant of REPACK; see repack.c */
 			cluster_rel(REPACK_COMMAND_VACUUMFULL, rel, InvalidOid,
 						&cluster_params);
 			/* cluster_rel closes the relation, but keeps lock */

src/backend/storage/ipc/procsignal.c

@@ -19,6 +19,7 @@
 
 #include "access/parallel.h"
 #include "commands/async.h"
+#include "commands/repack.h"
 #include "miscadmin.h"
 #include "pgstat.h"
 #include "port/pg_bitutils.h"

src/backend/tcop/postgres.c

@@ -39,6 +39,7 @@
 #include "commands/event_trigger.h"
 #include "commands/explain_state.h"
 #include "commands/prepare.h"
+#include "commands/repack.h"
 #include "common/pg_prng.h"
 #include "jit/jit.h"
 #include "libpq/libpq.h"

src/backend/tcop/utility.c

@@ -26,7 +26,6 @@
 #include "catalog/toasting.h"
 #include "commands/alter.h"
 #include "commands/async.h"
-#include "commands/cluster.h"
 #include "commands/collationcmds.h"
 #include "commands/comment.h"
 #include "commands/conversioncmds.h"
@@ -46,6 +45,7 @@
 #include "commands/proclang.h"
 #include "commands/propgraphcmds.h"
 #include "commands/publicationcmds.h"
+#include "commands/repack.h"
 #include "commands/schemacmds.h"
 #include "commands/seclabel.h"
 #include "commands/sequence.h"

src/include/commands/repack.h

@@ -1,17 +1,17 @@
 /*-------------------------------------------------------------------------
  *
- * cluster.h
- *	  header file for postgres cluster command stuff
+ * repack.h
+ *	  header file for the REPACK command
  *
  * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994-5, Regents of the University of California
  *
- * src/include/commands/cluster.h
+ * src/include/commands/repack.h
  *
  *-------------------------------------------------------------------------
  */
-#ifndef CLUSTER_H
-#define CLUSTER_H
+#ifndef REPACK_H
+#define REPACK_H
 
 #include "nodes/parsenodes.h"
 #include "parser/parse_node.h"
@@ -52,4 +52,4 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap,
 							 MultiXactId cutoffMulti,
 							 char newrelpersistence);
 
-#endif							/* CLUSTER_H */
+#endif							/* REPACK_H */