Avoid most stat calls when completing file names

* admin/merge-gnulib (GNULIB_MODULES): Add d-type.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.
* m4/d-type.m4: New file, copied from gnulib.
* src/dired.c (DT_UNKNOWN, DT_DIR, DT_LINK)
[!HAVE_STRUCT_DIRENT_D_TYPE]: New constants.
(dirent_type): New function.
(file_name_completion): Use it, to avoid unnecessary calls to
stat-like functions on GNU/Linux and other platforms with d_type.
(file_name_completion_stat): Just follow the link; there is no
need to try first with AT_SYMLINK_NOFOLLOW since the directory
entry was already checked to exist.

1 files changed, 2 insertions, 1 deletions

diff --git a/admin/merge-gnulib b/admin/merge-gnulib
index 18c9ee8def7..c23e8a40ea7 100755
--- a/admin/merge-gnulib
+++ b/admin/merge-gnulib
@@ -30,7 +30,8 @@ GNULIB_MODULES='
   careadlinkat close-stream
   count-leading-zeros count-one-bits count-trailing-zeros
   crypto/md5 crypto/sha1 crypto/sha256 crypto/sha512
-  diffseq dtoastr dtotimespec dup2 environ execinfo explicit_bzero faccessat
+  d-type diffseq dtoastr dtotimespec dup2
+  environ execinfo explicit_bzero faccessat
   fcntl fcntl-h fdatasync fdopendir
   filemode filevercmp flexmember fstatat fsync
   getloadavg getopt-gnu gettime gettimeofday gitlog-to-changelog