(***********************************************************************)
(*                                                                     *)
(*                         Caml Special Light                          *)
(*                                                                     *)
(*            Xavier Leroy, projet Cristal, INRIA Rocquencourt         *)
(*                                                                     *)
(*  Copyright 1995 Institut National de Recherche en Informatique et   *)
(*  Automatique.  Distributed only by permission.                      *)
(*                                                                     *)
(***********************************************************************)

(* $Id$ *)

(* CRC computation *)

external unsafe_for_string: string -> int -> int -> int = "crc_string"

let for_string str ofs len =
  if ofs < 0 or ofs + len > String.length str
  then invalid_arg "Crc.for_string"
  else unsafe_for_string str ofs len

external for_channel: in_channel -> int -> int = "crc_chan"