Don't process parser digest list if it is not signed

Add-digest-list-plugin.patch

@@ -1,4 +1,4 @@
-From 9b592f7c093d1161aad6abdc9ae00e42b72f15ba Mon Sep 17 00:00:00 2001
+From 7b446e502dc35d02ede0cde4499878e43ec498d9 Mon Sep 17 00:00:00 2001
 From: Roberto Sassu <roberto.sassu@huawei.com>
 Date: Wed, 26 Feb 2020 15:54:24 +0100
 Subject: [PATCH 2/3] Add digest list plugin
@@ -6,10 +6,10 @@ Subject: [PATCH 2/3] Add digest list plugin
 ---
  macros.in             |   1 +
  plugins/Makefile.am   |   4 +
- plugins/digest_list.c | 490 ++++++++++++++++++++++++++++++++++++++++++
+ plugins/digest_list.c | 493 ++++++++++++++++++++++++++++++++++++++++++
  rpmio/digest.h        |   1 +
  rpmio/rpmpgp.c        |   3 +
- 5 files changed, 499 insertions(+)
+ 5 files changed, 502 insertions(+)
  create mode 100644 plugins/digest_list.c
 
 diff --git a/macros.in b/macros.in
@@ -38,10 +38,10 @@ index d4ef039ed..07aa3585b 100644
 +plugins_LTLIBRARIES += digest_list.la
 diff --git a/plugins/digest_list.c b/plugins/digest_list.c
 new file mode 100644
-index 000000000..607987947
+index 000000000..465f95997
 --- /dev/null
 +++ b/plugins/digest_list.c
-@@ -0,0 +1,490 @@
+@@ -0,0 +1,493 @@
 +#include "system.h"
 +#include "errno.h"
 +
@@ -441,6 +441,9 @@ index 000000000..607987947
 +	if (!stat(path_sig, &st))
 +		digest_list_signed = 1;
 +
++	if (parser && !digest_list_signed)
++		goto out;
++
 +	if (parser)
 +		snprintf(path, PATH_MAX, "%s/0-parser_list-compact-libexec",
 +			 DIGEST_LIST_DEFAULT_PATH);