glob: port to NetBSD 9.2

Problem reported by Benno Schulenberg in:
https://lists.gnu.org/r/bug-gnulib/2022-04/msg00052.html
* doc/posix-functions/dirfd.texi: Document NetBSD 9.2 portability
bugs.  Remove an old common about errno that is no longer true
of POSIX 2018.
* lib/glob.c (glob_in_dir): Convert dirfd arg from void *
to DIR * before passing it to dirfd.

ChangeLog

@@ -1,3 +1,14 @@
+2022-04-26  Paul Eggert  <eggert@cs.ucla.edu>
+
+	glob: port to NetBSD 9.2
+	Problem reported by Benno Schulenberg in:
+	https://lists.gnu.org/r/bug-gnulib/2022-04/msg00052.html
+	* doc/posix-functions/dirfd.texi: Document NetBSD 9.2 portability
+	bugs.  Remove an old common about errno that is no longer true
+	of POSIX 2018.
+	* lib/glob.c (glob_in_dir): Convert dirfd arg from void *
+	to DIR * before passing it to dirfd.
+
 2022-04-20  Paul Eggert  <eggert@cs.ucla.edu>
 
 	backupfile: fix bug when renaming simple backups

doc/posix-functions/dirfd.texi

@@ -18,8 +18,9 @@ Portability problems not fixed by Gnulib:
 @item
 This function always fails on some platforms:
 mingw.
-@end itemize
 
-With the @code{dirfd} module, this functions always sets @code{errno} when it
-fails. (POSIX does not require that @code{dirfd} sets @code{errno} when it
-fails.)
+@item
+There is a @code{dirfd} macro but no function, and the macro does not
+work with an argument of type @code{void *}, as a function would:
+NetBSD 9.2.
+@end itemize

lib/glob.c

@@ -1358,7 +1358,8 @@ glob_in_dir (const char *pattern, const char *directory, int flags,
         }
       else
         {
-          int dfd = dirfd (stream);
+          DIR *dirp = stream;
+          int dfd = dirfd (dirp);
           int fnm_flags = ((!(flags & GLOB_PERIOD) ? FNM_PERIOD : 0)
                            | ((flags & GLOB_NOESCAPE) ? FNM_NOESCAPE : 0));
           flags |= GLOB_MAGCHAR;