From c3db8a2e2ea4498d87060a1f5101c12055a4b174 Mon Sep 17 00:00:00 2001 From: Michael Paquier Date: Sat, 28 May 2022 12:12:58 +0900 Subject: [PATCH] Handle NULL for short descriptions of custom GUC variables If a short description is specified as NULL in one of the various DefineCustomXXXVariable() functions available to external modules to define a custom parameter, SHOW ALL would crash. This change teaches SHOW ALL to properly handle NULL short descriptions, as well as any code paths that manipulate it, to gain in flexibility. Note that help_config.c was already able to do that, when describing a set of GUCs for postgres --describe-config. Author: Steve Chavez Reviewed by: Nathan Bossart, Andres Freund, Michael Paquier, Tom Lane Discussion: https://postgr.es/m/CAGRrpzY6hO-Kmykna_XvsTv8P2DshGiU6G3j8yGao4mk0CqjHA%40mail.gmail.com Backpatch-through: 10 --- src/backend/utils/misc/guc.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c index 1ffa1780cbe..ef0f7812603 100644 --- a/src/backend/utils/misc/guc.c +++ b/src/backend/utils/misc/guc.c @@ -8322,7 +8322,16 @@ ShowAllGUCConfig(DestReceiver *dest) isnull[1] = true; } - values[2] = PointerGetDatum(cstring_to_text(conf->short_desc)); + if (conf->short_desc) + { + values[2] = PointerGetDatum(cstring_to_text(conf->short_desc)); + isnull[2] = false; + } + else + { + values[2] = PointerGetDatum(NULL); + isnull[2] = true; + } /* send it to dest */ do_tup_output(tstate, values, isnull); @@ -8334,7 +8343,8 @@ ShowAllGUCConfig(DestReceiver *dest) pfree(setting); pfree(DatumGetPointer(values[1])); } - pfree(DatumGetPointer(values[2])); + if (conf->short_desc) + pfree(DatumGetPointer(values[2])); } end_tup_output(tstate); -- 2.47.2