* fix blocking issue on Windows : issue #793.

      Adding await_readable before reading fd

* fix broken pipe exception : issue #792.
      Use Unix.read_bigarray instead of Unix_cstruct.read

* replace eio_windows_cstruct_stubs.c by Unix functions.
     Since Ocaml 5.2, Unix.read_bigarray and Unix.write_bigarray can be used.

Author: bdodrem

lib_eio_windows/dune

@@ -6,7 +6,7 @@
  (foreign_stubs
   (language c)
   (include_dirs ../lib_eio/unix/include)
-  (names eio_windows_stubs eio_windows_cstruct_stubs))
+  (names eio_windows_stubs ))
  (c_library_flags :standard -lbcrypt -lntdll)
  (libraries eio eio.unix eio.utils fmt))
 

lib_eio_windows/eio_windows_cstruct_stubs.c

@@ -39,17 +39,25 @@ let rec do_nonblocking ty fn fd =
     do_nonblocking ty fn fd
 
 let read fd buf start len =
+  await_readable fd;
   Fd.use_exn "read" fd @@ fun fd ->
   do_nonblocking Read (fun fd -> Unix.read fd buf start len) fd
 
-let read_cstruct fd buf =
+let read_cstruct fd (buf:Cstruct.t) =
+  await_readable fd;
   Fd.use_exn "read_cstruct" fd @@ fun fd ->
-  do_nonblocking Read (fun fd -> Unix_cstruct.read fd buf) fd
+  do_nonblocking Read (fun fd -> Unix.read_bigarray fd buf.buffer buf.off buf.len) fd
 
 let write fd buf start len =
+  await_writable fd;
   Fd.use_exn "write" fd @@ fun fd ->
   do_nonblocking Write (fun fd -> Unix.write fd buf start len) fd
 
+let write_cstruct fd (buf:Cstruct.t) =
+  await_writable fd;
+  Fd.use_exn "write_cstruct" fd @@ fun fd ->
+  do_nonblocking Write (fun fd -> Unix.write_bigarray fd buf.buffer buf.off buf.len) fd
+
 let sleep_until time =
   Sched.enter @@ fun t k ->
   Sched.await_timeout t k time
@@ -148,8 +156,11 @@ let readv fd bufs =
   do_nonblocking Read (fun fd -> eio_readv fd bufs) fd
 
 let writev fd bufs =
-  Fd.use_exn "writev" fd @@ fun fd ->
-  do_nonblocking Write (fun fd -> Unix_cstruct.writev fd bufs) fd
+  let rec loop buf = if Cstruct.length buf > 0 then begin
+    let n = write_cstruct fd buf in
+    loop @@ Cstruct.shift buf n
+  end in
+  List.iter loop bufs
 
 let preadv ~file_offset fd bufs =
   Fd.use_exn "preadv" fd @@ fun fd ->

lib_eio_windows/low_level.ml

@@ -22,6 +22,7 @@ val sleep_until : Mtime.t -> unit
 val read : fd -> bytes -> int -> int -> int
 val read_cstruct : fd -> Cstruct.t -> int
 val write : fd -> bytes -> int -> int -> int
+val write_cstruct : fd -> Cstruct.t -> int
 
 val socket : sw:Switch.t -> Unix.socket_domain -> Unix.socket_type -> int -> fd
 val connect : fd -> Unix.sockaddr -> unit