backupfile: new dir_fd args

New module opendirat with code taken from fts.
Use this module to let backupfile use a directory file descriptor.
* NEWS: Document the incompatible change.
* lib/backup-find.c (find_backup_file_name):
* lib/backup-rename.c (backup_file_rename):
New arg DIR_FD.
* lib/backupfile.c: Include stdint.h, for SIZE_MAX.
(SIZE_MAX): Remove.
Include opendirat.h rather than dirent--.h.
(check_extension): New args DIR_FD and BASE_MAX.  All callers changed.
(numbered_backup): New args DIR_FD and PNEW_FD.  All callers changed.
(backupfile_internal): New arg DIR_FD.  All callers changed.
* lib/fts.c: Include opendirat.h.
(opendirat): Move to opendirat.c.
* lib/opendirat.c, lib/opendirat.h, modules/opendirat: New files.
* modules/backupfile (Depends-on): Remove dirfd, opendir.
Add opendirat.
* modules/fts (Depends-on): Remove fdopendir, openat-safer.
Add opendirat.

1 files changed, 1 insertions, 25 deletions

diff --git a/lib/fts.c b/lib/fts.c
index aaa6bb2934..5e8e89532f 100644
--- a/lib/fts.c
+++ b/lib/fts.c
@@ -73,6 +73,7 @@ static char sccsid[] = "@(#)fts.c       8.6 (Berkeley) 8/14/94";
 # include "fcntl--.h"
 # include "flexmember.h"
 # include "openat.h"
+# include "opendirat.h"
 # include "same-inode.h"
 #endif
 
@@ -294,31 +295,6 @@ fts_set_stat_required (FTSENT *p, bool required)
                            : FTS_NO_STAT_REQUIRED);
 }
 
-/* file-descriptor-relative opendir.  */
-/* FIXME: if others need this function, move it into lib/openat.c */
-static DIR *
-internal_function
-opendirat (int fd, char const *dir, int extra_flags, int *pdir_fd)
-{
-  int open_flags = (O_RDONLY | O_CLOEXEC | O_DIRECTORY | O_NOCTTY
-                    | O_NONBLOCK | extra_flags);
-  int new_fd = openat (fd, dir, open_flags);
-  DIR *dirp;
-
-  if (new_fd < 0)
-    return NULL;
-  dirp = fdopendir (new_fd);
-  if (dirp)
-    *pdir_fd = new_fd;
-  else
-    {
-      int saved_errno = errno;
-      close (new_fd);
-      errno = saved_errno;
-    }
-  return dirp;
-}
-
 /* Virtual fchdir.  Advance SP's working directory file descriptor,
    SP->fts_cwd_fd, to FD, and push the previous value onto the fd_ring.
    CHDIR_DOWN_ONE is true if FD corresponds to an entry in the directory