(*
 * Copyright (c) 2012 Anil Madhavapeddy <anil@recoil.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *)

let read fd t =
  Lwt_bytes.read fd t.Cstruct.buffer t.Cstruct.off t.Cstruct.len

let write fd t =
  Lwt_bytes.write fd t.Cstruct.buffer t.Cstruct.off t.Cstruct.len

let complete op t =
  let open Lwt in
  let rec loop t =
    op t >>= fun n ->
    let t = Cstruct.shift t n in
    if Cstruct.length t = 0
    then return ()
    else if n = 0
    then fail End_of_file
    else loop t in
  loop t

let sendto fd t flags dst =
  Lwt_bytes.sendto fd t.Cstruct.buffer t.Cstruct.off t.Cstruct.len flags dst

let recvfrom fd t flags =
  Lwt_bytes.recvfrom fd t.Cstruct.buffer t.Cstruct.off t.Cstruct.len flags