mte/unikernel/duniverse/angstrom/lwt/angstrom_lwt_unix.ml
2025-11-11 02:07:51 +01:00

81 lines
3.1 KiB
OCaml

(*----------------------------------------------------------------------------
Copyright (c) 2016 Inhabited Type LLC.
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. Neither the name of the author nor the names of his contributors
may be used to endorse or promote products derived from this software
without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND ANY EXPRESS
OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
----------------------------------------------------------------------------*)
open Angstrom.Buffered
open Lwt
let default_pushback () = return_unit
let rec buffered_state_loop pushback state in_chan bytes =
let size = Bytes.length bytes in
match state with
| Partial k ->
Lwt_io.read_into in_chan bytes 0 size
>|= begin function
| 0 -> k `Eof
| len ->
assert (len > 0);
k (`String (Bytes.(unsafe_to_string (sub bytes 0 len))))
end
>>= fun state' -> pushback ()
>>= fun () -> buffered_state_loop pushback state' in_chan bytes
| state -> return state
let handle_parse_result state =
match state_to_unconsumed state with
| None -> assert false
| Some us -> us, state_to_result state
let parse ?(pushback=default_pushback) p in_chan =
let size = Lwt_io.buffer_size in_chan in
let bytes = Bytes.create size in
buffered_state_loop pushback (parse ~initial_buffer_size:size p) in_chan bytes
>|= handle_parse_result
let with_buffered_parse_state ?(pushback=default_pushback) state in_chan =
let size = Lwt_io.buffer_size in_chan in
let bytes = Bytes.create size in
begin match state with
| Partial _ -> buffered_state_loop pushback state in_chan bytes
| _ -> return state
end
>|= handle_parse_result
let async_many e k =
Angstrom.(skip_many (e <* commit >>| k) <?> "async_many")
let parse_many p write in_chan =
let wait = ref (default_pushback ()) in
let k x = wait := write x in
let pushback () = !wait in
parse ~pushback (async_many p k) in_chan