Don't report zero errno for inaccessible directory

* src/fileio.c (Ffile_accessible_directory_p): Report EACCES when
a file handler reports a failure.  (Bug#25419)

1 files changed, 8 insertions, 1 deletions

diff --git a/src/fileio.c b/src/fileio.c
index ac6d7819411..8e549a44855 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -2815,7 +2815,14 @@ really is a readable and searchable directory.  */)
   if (!NILP (handler))
     {
       Lisp_Object r = call2 (handler, Qfile_accessible_directory_p, absname);
-      errno = 0;
+
+      /* This might be a lie (e.g., the directory might not exist, or
+         be a regular file), but at least it does TRT in the "usual"
+         case of an existing directory that is not accessible by the
+         current user, and avoids reporting "Success" for a failed
+         operation.  */
+      if (!EQ (r, Qt))
+        errno = EACCES;
       return r;
     }