Adds -n option: wait on finnishing grandchild process

https://github.com/cronie-crond/cronie/pull/163

cronie.spec

@@ -11,6 +11,9 @@ License:   GPL-2.0-or-later AND BSD-3-Clause AND BSD-2-Clause AND ISC AND LGPL-2
 URL:       https://github.com/cronie-crond/cronie
 Source0:   https://github.com/cronie-crond/cronie/releases/download/cronie-%{version}/cronie-%{version}.tar.gz
 
+# https://github.com/cronie-crond/cronie/pull/163
+Patch:     n_option_wait_on_finnishing_grandchild_process.patch
+
 Requires:  dailyjobs
 
 %if %{with selinux}

n_option_wait_on_finnishing_grandchild_process.patch

@@ -0,0 +1,25 @@
+From 5cf85f8cbb816ff1df5b317d6f8559b67e1993dd Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Ond=C5=99ej=20Poho=C5=99elsk=C3=BD?= <opohorel@redhat.com>
+Date: Wed, 25 Oct 2023 10:58:46 +0200
+Subject: [PATCH] -n option: wait on finnishing grandchild process
+
+With `WNOHANG` we skip sending the email when waitpid() returns 0,
+which happens if the process is still running. Instead, using `0`
+parameter will wait for the process to actually stop running.
+---
+ src/do_command.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/do_command.c b/src/do_command.c
+index d7ca840..2ada913 100644
+--- a/src/do_command.c
++++ b/src/do_command.c
+@@ -579,7 +579,7 @@ static int child_process(entry * e, char **jobenv) {
+ 			if (mail && e->flags & MAIL_WHEN_ERR) {
+ 				int jobstatus = -1;
+ 				if (jobpid > 0) {
+-					while (waitpid(jobpid, &jobstatus, WNOHANG) == -1) {
++					while (waitpid(jobpid, &jobstatus, 0) == -1) {
+ 						if (errno == EINTR) continue;
+ 						log_it("CRON", getpid(), "error", "invalid job pid", errno);
+ 						break;