;;;; Copyright (C) 2020 Julien Lepiller <julien@lepiller.eu>

;;;; 

;;;; This library is free software; you can redistribute it and/or

;;;; modify it under the terms of the GNU Lesser General Public

;;;; License as published by the Free Software Foundation; either

;;;; version 3 of the License, or (at your option) any later version.

;;;; 

;;;; This library is distributed in the hope that it will be useful,

;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of

;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

;;;; Lesser General Public License for more details.

;;;; 

;;;; You should have received a copy of the GNU Lesser General Public

;;;; License along with this library; if not, write to the Free Software

;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

;;;; 

(define-module (netlink standard)

  #:use-module (ice-9 match)

  #:use-module (netlink data)

  #:use-module (netlink message)

  #:use-module (srfi srfi-9)

  #:use-module (rnrs bytevectors)

  #:export (make-error-message

            error-message?

            error-message-hdr

            error-message-err

            deserialize-error-message

            no-data

            deserialize-no-data))

(define-data-type error-message

  (lambda (msg)

    (+ 4 (data-size (error-message-type-hdr msg))))

  (lambda (msg pos bv)

    (match msg

     (($ error-message-type err hdr)

      (bytevector-s32-set! bv pos err (native-endianness))

      (serialize hdr (+ 4 pos) bv))))

  (err error-message-err error-message-type-err)

  (hdr error-message-hdr error-message-type-hdr))

(define (deserialize-error-message decoder bv pos)

  (make-error-message

    (bytevector-s32-ref bv pos (native-endianness))

    (deserialize 'message-hdr decoder (pk 'error-mrg bv) (+ pos 4))))

(define no-data

  (make-nl-data

    #f

    (const 0)

    (const (make-bytevector 0))))

(define (deserialize-no-data decoder bv pos)

  no-data)