Add construct_array_builtin, deconstruct_array_builtin

There were many calls to construct_array() and deconstruct_array() for
built-in types, for example, when dealing with system catalog columns.
These all hardcoded the type attributes necessary to pass to these
functions.

To simplify this a bit, add construct_array_builtin(),
deconstruct_array_builtin() as wrappers that centralize this hardcoded
knowledge.  This simplifies many call sites and reduces the amount of
hardcoded stuff that is spread around.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/2914356f-9e5f-8c59-2995-5997fc48bcba%40enterprisedb.com

5 files changed, 8 insertions, 30 deletions

diff --git a/contrib/pageinspect/btreefuncs.c b/contrib/pageinspect/btreefuncs.c
index 62f2c1b3159..9375d55e149 100644
--- a/contrib/pageinspect/btreefuncs.c
+++ b/contrib/pageinspect/btreefuncs.c
@@ -425,11 +425,7 @@ bt_page_print_tuples(struct user_args *uargs)
 		tids_datum = (Datum *) palloc(nposting * sizeof(Datum));
 		for (int i = 0; i < nposting; i++)
 			tids_datum[i] = ItemPointerGetDatum(&tids[i]);
-		values[j++] = PointerGetDatum(construct_array(tids_datum,
-													  nposting,
-													  TIDOID,
-													  sizeof(ItemPointerData),
-													  false, TYPALIGN_SHORT));
+		values[j++] = PointerGetDatum(construct_array_builtin(tids_datum, nposting, TIDOID));
 		pfree(tids_datum);
 	}
 	else
diff --git a/contrib/pageinspect/ginfuncs.c b/contrib/pageinspect/ginfuncs.c
index 31aca7b0006..952e9d51a87 100644
--- a/contrib/pageinspect/ginfuncs.c
+++ b/contrib/pageinspect/ginfuncs.c
@@ -166,9 +166,7 @@ gin_page_opaque_info(PG_FUNCTION_ARGS)
 
 	values[0] = Int64GetDatum(opaq->rightlink);
 	values[1] = Int32GetDatum(opaq->maxoff);
-	values[2] = PointerGetDatum(construct_array(flags, nflags,
-												TEXTOID,
-												-1, false, TYPALIGN_INT));
+	values[2] = PointerGetDatum(construct_array_builtin(flags, nflags, TEXTOID));
 
 	/* Build and return the result tuple. */
 	resultTuple = heap_form_tuple(tupdesc, values, nulls);
@@ -273,11 +271,7 @@ gin_leafpage_items(PG_FUNCTION_ARGS)
 		tids_datum = (Datum *) palloc(ndecoded * sizeof(Datum));
 		for (i = 0; i < ndecoded; i++)
 			tids_datum[i] = ItemPointerGetDatum(&tids[i]);
-		values[2] = PointerGetDatum(construct_array(tids_datum,
-													ndecoded,
-													TIDOID,
-													sizeof(ItemPointerData),
-													false, TYPALIGN_SHORT));
+		values[2] = PointerGetDatum(construct_array_builtin(tids_datum, ndecoded, TIDOID));
 		pfree(tids_datum);
 		pfree(tids);
 
diff --git a/contrib/pageinspect/gistfuncs.c b/contrib/pageinspect/gistfuncs.c
index 4943d6f75bd..d0a34a33756 100644
--- a/contrib/pageinspect/gistfuncs.c
+++ b/contrib/pageinspect/gistfuncs.c
@@ -104,9 +104,7 @@ gist_page_opaque_info(PG_FUNCTION_ARGS)
 	values[0] = LSNGetDatum(PageGetLSN(page));
 	values[1] = LSNGetDatum(GistPageGetNSN(page));
 	values[2] = Int64GetDatum(opaq->rightlink);
-	values[3] = PointerGetDatum(construct_array(flags, nflags,
-												TEXTOID,
-												-1, false, TYPALIGN_INT));
+	values[3] = PointerGetDatum(construct_array_builtin(flags, nflags, TEXTOID));
 
 	/* Build and return the result tuple. */
 	resultTuple = heap_form_tuple(tupdesc, values, nulls);
diff --git a/contrib/pageinspect/hashfuncs.c b/contrib/pageinspect/hashfuncs.c
index 69af7b962ff..5287dbe1a30 100644
--- a/contrib/pageinspect/hashfuncs.c
+++ b/contrib/pageinspect/hashfuncs.c
@@ -564,21 +564,11 @@ hash_metapage_info(PG_FUNCTION_ARGS)
 
 	for (i = 0; i < HASH_MAX_SPLITPOINTS; i++)
 		spares[i] = Int64GetDatum((int64) metad->hashm_spares[i]);
-	values[j++] = PointerGetDatum(construct_array(spares,
-												  HASH_MAX_SPLITPOINTS,
-												  INT8OID,
-												  sizeof(int64),
-												  FLOAT8PASSBYVAL,
-												  TYPALIGN_DOUBLE));
+	values[j++] = PointerGetDatum(construct_array_builtin(spares, HASH_MAX_SPLITPOINTS, INT8OID));
 
 	for (i = 0; i < HASH_MAX_BITMAPS; i++)
 		mapp[i] = Int64GetDatum((int64) metad->hashm_mapp[i]);
-	values[j++] = PointerGetDatum(construct_array(mapp,
-												  HASH_MAX_BITMAPS,
-												  INT8OID,
-												  sizeof(int64),
-												  FLOAT8PASSBYVAL,
-												  TYPALIGN_DOUBLE));
+	values[j++] = PointerGetDatum(construct_array_builtin(mapp, HASH_MAX_BITMAPS, INT8OID));
 
 	tuple = heap_form_tuple(tupleDesc, values, nulls);
 
diff --git a/contrib/pageinspect/heapfuncs.c b/contrib/pageinspect/heapfuncs.c
index 3dd1a9bc2ab..a654234c6bd 100644
--- a/contrib/pageinspect/heapfuncs.c
+++ b/contrib/pageinspect/heapfuncs.c
@@ -590,7 +590,7 @@ heap_tuple_infomask_flags(PG_FUNCTION_ARGS)
 
 	/* build value */
 	Assert(cnt <= bitcnt);
-	a = construct_array(flags, cnt, TEXTOID, -1, false, TYPALIGN_INT);
+	a = construct_array_builtin(flags, cnt, TEXTOID);
 	values[0] = PointerGetDatum(a);
 
 	/*
@@ -612,7 +612,7 @@ heap_tuple_infomask_flags(PG_FUNCTION_ARGS)
 	if (cnt == 0)
 		a = construct_empty_array(TEXTOID);
 	else
-		a = construct_array(flags, cnt, TEXTOID, -1, false, TYPALIGN_INT);
+		a = construct_array_builtin(flags, cnt, TEXTOID);
 	pfree(flags);
 	values[1] = PointerGetDatum(a);