Source file protocol_store.ml

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type t = {
  protocol_store_dir : [`Protocol_dir] Naming.directory;
  mutable protocols : Protocol_hash.Set.t;
}

let mem t protocol_hash = Protocol_hash.Set.mem protocol_hash t.protocols

let all {protocols; _} = protocols

let raw_store store protocol_hash bytes =
  let open Lwt_syntax in
  if mem store protocol_hash then Lwt.return_none
  else
    let protocol_file =
      Naming.protocol_file store.protocol_store_dir protocol_hash
    in
    let* fd =
      Lwt_unix.openfile
        (Naming.file_path protocol_file)
        [Unix.O_CREAT; O_WRONLY; O_CLOEXEC]
        0o644
    in
    let* () = Lwt_utils_unix.write_bytes fd bytes in
    let* _ = Lwt_utils_unix.safe_close fd in
    store.protocols <- Protocol_hash.Set.add protocol_hash store.protocols ;
    Lwt.return_some protocol_hash

let store store protocol_hash protocol =
  raw_store store protocol_hash (Protocol.to_bytes protocol)

let read store protocol_hash =
  let open Lwt_syntax in
  Option.catch_os (fun () ->
      let protocol_file =
        Naming.protocol_file store.protocol_store_dir protocol_hash
      in
      let* content =
        Lwt_utils_unix.read_file (Naming.file_path protocol_file)
      in
      Lwt.return (Protocol.of_string content))

let init store_dir =
  let open Lwt_syntax in
  let protocol_store_dir = Naming.protocol_store_dir store_dir in
  let protocol_store_dir_path = Naming.dir_path protocol_store_dir in
  let* file_exists = Lwt_unix.file_exists protocol_store_dir_path in
  let* () =
    if not file_exists then Lwt_utils_unix.create_dir protocol_store_dir_path
    else Lwt.return_unit
  in
  let* dir = Lwt_unix.opendir protocol_store_dir_path in
  let rec loop set =
    Lwt.try_bind
      (fun () -> Lwt_unix.readdir dir)
      (fun file ->
        match Protocol_hash.of_b58check_opt file with
        | Some protocol_hash -> loop (Protocol_hash.Set.add protocol_hash set)
        | None -> loop set)
      (function End_of_file -> Lwt.return set | _ -> loop set)
  in
  let* protocols = loop Protocol_hash.Set.empty in
  let* () = Lwt_unix.closedir dir in
  Lwt.return {protocol_store_dir; protocols}