[PATCH] src_postinst.cygpart: Sanitize binary data in bash command subst

[Eric Blake <eblake@redhat.com>]

bash 4.4 now warns about skipping NUL bytes in $(command), since
command substitution is only well-formed for commands that output
text, but NUL bytes are not text.  Silence the warning by removing
NUL bytes from the stream before bash can see them.
---
 lib/src_postinst.cygpart | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/src_postinst.cygpart b/lib/src_postinst.cygpart
index 30ad90e..2ae26b6 100644
--- a/lib/src_postinst.cygpart
+++ b/lib/src_postinst.cygpart
@@ -967,14 +967,14 @@ __prepstrip() {
 		# Magic number is at end of file:
 		# http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=256900#74
 		# http://cygwin.com/ml/cygwin-apps/2010-10/msg00057.html
-		case $(tail -c 12 "${exe}") in
+		case $(tail -c 12 "${exe}" | tr -d '\0') in
 			Caml1999X0[0-9][0-9])  continue ;;
 		esac

 		# Perl Archive (PAR) binaries must not be stripped
 		# https://rt.cpan.org/Public/Bug/Display.html?id=18536
 		# http://cygwin.com/ml/cygwin-apps/2012-07/msg00088.html
-		case $(tail -c 8 "${exe}" | tr '\012' '%') in
+		case $(tail -c 8 "${exe}" | tr '\012\0' '%') in
 			%PAR\.pm%)  continue ;;
 		esac

-- 
2.9.3