From dcc2eb693c70936627e8c9af32b93bcc35d6cd5e Mon Sep 17 00:00:00 2001 From: Thomas Munro Date: Mon, 2 Mar 2026 04:21:02 +1300 Subject: [PATCH v2 15/19] Use stack buffer in some FDW code. Mechanical changes to temporary datum and null arrays. --- contrib/file_fdw/file_fdw.c | 11 +++++++---- contrib/postgres_fdw/postgres_fdw.c | 9 +++++++-- 2 files changed, 14 insertions(+), 6 deletions(-) diff --git a/contrib/file_fdw/file_fdw.c b/contrib/file_fdw/file_fdw.c index 33a37d832ce..a6958d6a4c0 100644 --- a/contrib/file_fdw/file_fdw.c +++ b/contrib/file_fdw/file_fdw.c @@ -40,6 +40,7 @@ #include "utils/memutils.h" #include "utils/rel.h" #include "utils/sampling.h" +#include "utils/stack_buffer.h" #include "utils/varlena.h" PG_MODULE_MAGIC_EXT( @@ -1202,12 +1203,14 @@ file_acquire_sample_rows(Relation onerel, int elevel, MemoryContext oldcontext = CurrentMemoryContext; MemoryContext tupcontext; + DECLARE_STACK_BUFFER(); + Assert(onerel); Assert(targrows > 0); tupDesc = RelationGetDescr(onerel); - values = (Datum *) palloc(tupDesc->natts * sizeof(Datum)); - nulls = (bool *) palloc(tupDesc->natts * sizeof(bool)); + values = stack_buffer_alloc_array(Datum, tupDesc->natts); + nulls = stack_buffer_alloc_array(bool, tupDesc->natts); /* Fetch options of foreign table */ fileGetOptions(RelationGetRelid(onerel), &filename, &is_program, &options); @@ -1324,8 +1327,8 @@ file_acquire_sample_rows(Relation onerel, int elevel, EndCopyFrom(cstate); - pfree(values); - pfree(nulls); + stack_buffer_free(values); + stack_buffer_free(nulls); /* * Emit some interesting relation info diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 60d90329a65..c817b718616 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -48,6 +48,7 @@ #include "utils/rel.h" #include "utils/sampling.h" #include "utils/selfuncs.h" +#include "utils/stack_buffer.h" PG_MODULE_MAGIC_EXT( .name = "postgres_fdw", @@ -7507,6 +7508,8 @@ make_tuple_from_result_row(PGresult *res, ListCell *lc; int j; + DECLARE_STACK_BUFFER(); + Assert(row < PQntuples(res)); /* @@ -7528,8 +7531,8 @@ make_tuple_from_result_row(PGresult *res, tupdesc = fsstate->ss.ss_ScanTupleSlot->tts_tupleDescriptor; } - values = (Datum *) palloc0(tupdesc->natts * sizeof(Datum)); - nulls = (bool *) palloc(tupdesc->natts * sizeof(bool)); + values = stack_buffer_alloc0_array(Datum, tupdesc->natts); + nulls = stack_buffer_alloc_array(bool, tupdesc->natts); /* Initialize to nulls for any columns not present in result */ memset(nulls, true, tupdesc->natts * sizeof(bool)); @@ -7631,6 +7634,8 @@ make_tuple_from_result_row(PGresult *res, HeapTupleHeaderSetCmin(tuple->t_data, InvalidTransactionId); /* Clean up */ + stack_buffer_free(values); + stack_buffer_free(nulls); MemoryContextReset(temp_context); return tuple; -- 2.53.0