Add mkdirat

lib/uring/uring.ml

@@ -331,6 +331,7 @@ module Uring = struct
   external submit_openat2 : t -> id -> Unix.file_descr -> Open_how.t -> bool = "ocaml_uring_submit_openat2" [@@noalloc]
   external submit_linkat : t -> id -> Unix.file_descr -> Sketch.ptr -> Unix.file_descr -> Sketch.ptr -> int -> bool = "ocaml_uring_submit_linkat_byte" "ocaml_uring_submit_linkat_native" [@@noalloc]
   external submit_unlinkat : t -> id -> Unix.file_descr -> Sketch.ptr -> bool -> bool = "ocaml_uring_submit_unlinkat" [@@noalloc]
+  external submit_mkdirat : t -> id -> Unix.file_descr -> Sketch.ptr -> int -> bool = "ocaml_uring_submit_mkdirat" [@@noalloc]
   external submit_send_msg : t -> id -> Unix.file_descr -> Msghdr.t -> Sketch.ptr -> bool = "ocaml_uring_submit_send_msg" [@@noalloc]
   external submit_recv_msg : t -> id -> Unix.file_descr -> Msghdr.t -> Sketch.ptr -> bool = "ocaml_uring_submit_recv_msg" [@@noalloc]
   external submit_fsync : t -> id -> Unix.file_descr -> int64 -> int -> bool = "ocaml_uring_submit_fsync" [@@noalloc]
@@ -487,6 +488,12 @@ let unlink t ~dir ?(fd=at_fdcwd) path user_data =
       Uring.submit_unlinkat t.uring id fd buf dir
     ) user_data
 
+let mkdirat t ~mode ?(fd=at_fdcwd) path user_data =
+  with_id t (fun id ->
+      let buf = Sketch.String.alloc t.sketch path in
+      Uring.submit_mkdirat t.uring id fd buf mode
+    ) user_data
+
 let read t ~file_offset fd (buf : Cstruct.t) user_data =
   with_id_full t (fun id -> Uring.submit_read t.uring fd id buf file_offset) user_data ~extra_data:buf
 

lib/uring/uring.mli

@@ -284,6 +284,11 @@ val unlink : 'a t -> dir:bool -> ?fd:Unix.file_descr -> string -> 'a -> 'a job o
     @param dir If [true], this acts like [rmdir] (only removing empty directories).
                If [false], it acts like [unlink] (only removing non-directories). *)
 
+val mkdirat : 'a t -> mode:Unix.file_perm -> ?fd:Unix.file_descr -> string -> 'a -> 'a job option
+(** [mkdirat t ~mode ~fd path] makes a directory [path], which is resolved relative to [fd].
+    If [fd] is not given, then the current working directory is used.
+    @param mode The mode used to create the directory. *)
+
 module Poll_mask : sig
   include FLAGS
 

lib/uring/uring_stubs.c

@@ -853,6 +853,17 @@ ocaml_uring_submit_unlinkat(value v_uring, value v_id, value v_fd, value v_sketc
   return (Val_true);
 }
 
+value /* noalloc */
+ocaml_uring_submit_mkdirat(value v_uring, value v_id, value v_fd, value v_sketch_ptr, value v_mode) {
+  struct io_uring *ring = Ring_val(v_uring);
+  struct io_uring_sqe *sqe = io_uring_get_sqe(ring);
+  char *path = Sketch_ptr_val(v_sketch_ptr);
+  if (!sqe) return (Val_false);
+  io_uring_prep_mkdirat(sqe, Int_val(v_fd), path, Int_val(v_mode));
+  io_uring_sqe_set_data(sqe, (void *)Long_val(v_id));
+  return (Val_true);
+}
+
 value /* noalloc */
 ocaml_uring_submit_fsync(value v_uring, value v_id, value v_fd, value v_off, value v_len)
 {

tests/main.md

@@ -865,6 +865,31 @@ This currently doesn't work due to https://github.com/axboe/liburing/issues/955:
 - : unit = ()
 ```
 
+## Mkdirat
+
+```ocaml
+# let t : [ `Mkdir of int ] Uring.t = Uring.create ~queue_depth:1 ();;
+val t : [ `Mkdir of int ] Uring.t = <abstr>
+# Uring.mkdirat t ~mode:0o755 "mkdir" (`Mkdir 0);;
+- : [ `Mkdir of int ] Uring.job option = Some <abstr>
+# Uring.submit t;;
+- : int = 1
+# Uring.wait t;;
+- : [ `Mkdir of int ] Uring.completion_option =
+Uring.Some {Uring.result = 0; data = `Mkdir 0}
+# (Unix.stat "mkdir").st_perm;;
+- : int = 448
+# let v = Uring.mkdirat t ~mode:0o755 "mkdir" (`Mkdir 1);;
+val v : [ `Mkdir of int ] Uring.job option = Some <abstr>
+# Uring.submit t;;
+- : int = 1
+# Uring.wait t;;
+- : [ `Mkdir of int ] Uring.completion_option =
+Uring.Some {Uring.result = -17; data = `Mkdir 1}
+# Uring.exit t;;
+- : unit = ()
+```
+
 ## Timeout
 
 Timeout should return (-ETIME). This is defined in https://github.com/torvalds/linux/blob/master/include/uapi/asm-generic/errno.h#L45