Source file `mirage_kv.ml`

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(*
 * Copyright (c) 2011-2015 Anil Madhavapeddy <anil@recoil.org>
 * Copyright (c) 2013-2015 Thomas Gazagnaire <thomas@gazagnaire.org>
 * Copyright (c) 2013      Citrix Systems Inc
 *
 * 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.
 *)

type error = [`Unknown_key of string]

let pp_error ppf = function
  | `Unknown_key k -> Fmt.pf ppf "key %s not present in the store" k

module type RO = sig
  type error = private [> `Unknown_key of string]
  val pp_error: error Fmt.t
  include Mirage_device.S
  type page_aligned_buffer
  val read: t -> string -> int64 -> int64 ->
    (page_aligned_buffer list, error) result io
  val mem: t -> string -> (bool, error) result io
  val size: t -> string -> (int64, error) result io
end