libsbutil: gnulib: import modules for canonicalize_filename_mode

This lays the groundwork for fixing handling of broken symlinks.  The
gnulib code is hand imported because using the gnulib tool imports a
ton of code we do not want.  Only the bare minimum is imported so we
can use the canonicalize_filename_mode function.

This function is needed to canonicalize symlinks that are ultimately
broken.  The current sandbox/C library code only supports two modes:
(1) dereference a single symlink
(2) dereference *all* symlinks, but only if all links are valid

For sandbox, we need to know the final path a symlink points to even
if that path doesn't (yet) exist.

Note: This commit doesn't actually fix the bug, just brings in the
functions we need to do so.

URL: https://bugs.gentoo.org/540828
Reported-by: Rick Farina <zerochaos@gentoo.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/headers.h b/headers.h
index 42b7c25..1dc140e 100644
--- a/headers.h
+++ b/headers.h
@@ -146,4 +146,6 @@
 # include "localdecls.h"
 #endif
 
+#include "libsbutil/gnulib/glue.h"
+
 #endif