Stub chmod on windows

Co-Authored-By: Daniel Ntege <[email protected]>

lib_eio/unix/stubs.c

@@ -55,6 +55,9 @@ CAMLprim value eio_unix_readlinkat(value v_fd, value v_path, value v_cs) {
 }
 
 CAMLprim value eio_unix_fchmodat(value v_fd, value v_path, value v_mode, value v_flags) {
+  #ifdef _WIN32
+  caml_unix_error(EOPNOTSUPP, "fchmodat not supported on Windows", v_path);
+  #else
   CAMLparam1(v_path);
   char *path;
   int ret;
@@ -66,4 +69,5 @@ CAMLprim value eio_unix_fchmodat(value v_fd, value v_path, value v_mode, value v
   caml_stat_free_preserving_errno(path);
   if (ret == -1) uerror("fchmodat", v_path);
   CAMLreturn(Val_unit);
+  #endif
 }

lib_eio_windows/fs.ml

@@ -185,6 +185,10 @@ end = struct
     Switch.on_release sw (fun () -> close d);
     Eio.Resource.T (d, Handler.v)
 
+  let chmod t ~follow:_ ~perm path =
+    with_parent_dir t path @@ fun dirfd path ->
+    Low_level.chmod ~mode:perm dirfd path
+
   let pp f t = Fmt.string f (String.escaped t.label)
 
   let native _t _path =

lib_eio_windows/low_level.ml

@@ -211,7 +211,7 @@ external eio_openat : Unix.file_descr option -> bool -> string -> Flags.Open.t -
 let openat ?dirfd ?(nofollow=false) ~sw path flags dis create =
   with_dirfd "openat" dirfd @@ fun dirfd ->
   Switch.check sw;
-  in_worker_thread (fun () -> eio_openat dirfd nofollow path Flags.Open.(flags + cloexec (* + nonblock *)) dis create)
+  in_worker_thread ~label:"openat" (fun () -> eio_openat dirfd nofollow path Flags.Open.(flags + cloexec (* + nonblock *)) dis create)
   |> Fd.of_unix ~sw ~blocking:false ~close_unix:true
 
 let mkdir ?dirfd ?(nofollow=false) ~mode:_ path =
@@ -223,25 +223,33 @@ external eio_unlinkat : Unix.file_descr option -> string -> bool -> unit = "caml
 
 let unlink ?dirfd ~dir path =
   with_dirfd "unlink" dirfd @@ fun dirfd ->
-  in_worker_thread @@ fun () ->
+  in_worker_thread ~label:"unlink" @@ fun () ->
   eio_unlinkat dirfd path dir
 
 external eio_renameat : Unix.file_descr option -> string -> Unix.file_descr option -> string -> unit = "caml_eio_windows_renameat"
 
 let rename ?old_dir old_path ?new_dir new_path =
   with_dirfd "rename-old" old_dir @@ fun old_dir ->
   with_dirfd "rename-new" new_dir @@ fun new_dir ->
-  in_worker_thread @@ fun () ->
+  in_worker_thread ~label:"rename" @@ fun () ->
   eio_renameat old_dir old_path new_dir new_path
 
 
 external eio_symlinkat : string -> Unix.file_descr option -> string -> unit = "caml_eio_windows_symlinkat"
 
 let symlink ~link_to new_dir new_path =
   with_dirfd "symlink-new" new_dir @@ fun new_dir ->
-  in_worker_thread @@ fun () ->
+  in_worker_thread ~label:"symlink" @@ fun () ->
   eio_symlinkat link_to new_dir new_path
 
+let chmod ~mode new_dir new_path =
+  with_dirfd "chmod" new_dir @@ fun new_dir ->
+  match new_dir with
+  | Some _ -> failwith "chmod not supported on Windows"
+  | None ->
+    in_worker_thread ~label:"chmod" @@ fun () ->
+    Unix.chmod new_path mode
+
 let lseek fd off cmd =
   Fd.use_exn "lseek" fd @@ fun fd ->
   let cmd =

lib_eio_windows/low_level.mli

@@ -52,6 +52,10 @@ val symlink : link_to:string -> fd option -> string -> unit
 (** [symlink ~link_to dir path] will create a new symlink at [dir / path]
     linking to [link_to]. *)
 
+val chmod : mode:int -> fd option -> string -> unit
+(** [chmod ~mode path] is just a non-blocking call to {! Unix.chmod} when
+    [fd = None], otherwise it is unsupported. *)
+
 val readdir : string -> string array
 
 val readv : fd -> Cstruct.t array -> int