Simplify SRFs using materialize mode in contrib/ modules

9e98583 introduced a helper to centralize building their needed state
(tuplestore, tuple descriptors, etc.), checking for any errors.  This
commit updates all places of contrib/ that can be switched to use
SetSingleFuncCall() as a drop-in replacement, resulting in the removal
of a lot of boilerplate code in all the modules updated by this commit.

Per analysis, some places remain as they are:
- pg_logdir_ls() in adminpack/ uses historically TYPEFUNC_RECORD as
return type, and I suspect that changing it may cause issues at run-time
with some of its past versions, down to 1.0.
- dblink/ uses a wrapper function doing exactly the work of
SetSingleFuncCall().  Here the switch should be possible, but rather
invasive so it does not seem the extra backpatch maintenance cost.
- tablefunc/, similarly, uses multiple helper functions with portions of
SetSingleFuncCall() spread across the code paths of this module.

Author: Melanie Plageman
Discussion: https://postgr.es/m/CAAKRu_bvDPJoL9mH6eYwvBpPtTGQwbDzfJbCM-OjkSZDu5yTPg@mail.gmail.com

1 files changed, 2 insertions, 24 deletions

diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c
index efc4c94301..a06d4bd12d 100644
--- a/contrib/dblink/dblink.c
+++ b/contrib/dblink/dblink.c
@@ -1928,12 +1928,6 @@ dblink_get_notify(PG_FUNCTION_ARGS)
 	PGconn	   *conn;
 	PGnotify   *notify;
 	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
-	TupleDesc	tupdesc;
-	Tuplestorestate *tupstore;
-	MemoryContext per_query_ctx;
-	MemoryContext oldcontext;
-
-	prepTuplestoreResult(fcinfo);
 
 	dblink_init();
 	if (PG_NARGS() == 1)
@@ -1941,23 +1935,7 @@ dblink_get_notify(PG_FUNCTION_ARGS)
 	else
 		conn = pconn->conn;
 
-	/* create the tuplestore in per-query memory */
-	per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
-	oldcontext = MemoryContextSwitchTo(per_query_ctx);
-
-	tupdesc = CreateTemplateTupleDesc(DBLINK_NOTIFY_COLS);
-	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "notify_name",
-					   TEXTOID, -1, 0);
-	TupleDescInitEntry(tupdesc, (AttrNumber) 2, "be_pid",
-					   INT4OID, -1, 0);
-	TupleDescInitEntry(tupdesc, (AttrNumber) 3, "extra",
-					   TEXTOID, -1, 0);
-
-	tupstore = tuplestore_begin_heap(true, false, work_mem);
-	rsinfo->setResult = tupstore;
-	rsinfo->setDesc = tupdesc;
-
-	MemoryContextSwitchTo(oldcontext);
+	SetSingleFuncCall(fcinfo, 0);
 
 	PQconsumeInput(conn);
 	while ((notify = PQnotifies(conn)) != NULL)
@@ -1980,7 +1958,7 @@ dblink_get_notify(PG_FUNCTION_ARGS)
 		else
 			nulls[2] = true;
 
-		tuplestore_putvalues(tupstore, tupdesc, values, nulls);
+		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
 
 		PQfreemem(notify);
 		PQconsumeInput(conn);