shell: add preceding newline to delimiter

at uses heredoc redirection to pass the script being executed
into user's defined $SHELL. However, the heredoc delimiter
is directly concatenated to the script's contents;
if these contents do not end with a newline,
the delimiter is attached to the last line of the script.

This patch adds a single newline to be always emmited before the
delimiter. This guarantees the delimiter is always on it's own
line. In case a newline is already present at the end of the original
script, this simply adds a single empty line; I cannot think of any
complication that could result from that.

Resolves: rhbz#2070450

at-3.2.2-shell.patch

@@ -41,7 +41,7 @@ diff -ur b/at.c a/at.c
  	fprintf(stderr, "<EOT>\n");
      }
 -    fprintf(fp, "\n");
-+    fprintf(fp, "marcinDELIMITER%08lx\n", i);
++    fprintf(fp, "\nmarcinDELIMITER%08lx\n", i);
      if (ferror(fp))
  	panic("Output error");
      fflush(fp);

at.spec

@@ -3,7 +3,7 @@
 Summary:    Job spooling tools
 Name:       at
 Version:    3.2.5
-Release:    2%{?dist}
+Release:    3%{?dist}
 # http://packages.debian.org/changelogs/pool/main/a/at/current/copyright
 # + install-sh is MIT license with changes under Public Domain
 License:    GPLv3+ and GPLv2+ and ISC and MIT and Public Domain
@@ -164,6 +164,9 @@ chown root:root %{_localstatedir}/spool/at/.SEQ
 %attr(0644,root,root)       /%{_unitdir}/atd.service
 
 %changelog
+* Thu Mar 31 2022 Jan Staněk <jstanek@redhat.com> - 3.2.5-3
+- Add preceding newline to delimiter in at-3.2.2-shell.patch
+
 * Tue Mar 08 2022 Ondřej Pohořelský <opohorel@redhat.com> - 3.2.5-2
 - Add mising directory and batch-job script into at-3.2.5-make.patch
 - Defined datadir in %%install section and listed batch-job in %%files section