mes/elf.mes

;;; -*-scheme-*-

;;; Mes --- Maxwell Equations of Software
;;; Copyright © 2016 Jan Nieuwenhuizen <janneke@gnu.org>
;;;
;;; scm.mes: This file is part of Mes.
;;;
;;; Mes is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; Mes 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 General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with Mes.  If not, see <http://www.gnu.org/licenses/>.

(define (i386:puts data length)
  `(
     #xba ,@(int->bv32 length)      ;; mov    $0xe,%edx
          #xb9 ,@(int->bv32 data)        ;; mov    $data,%ecx
          #xbb #x01 #x00 #x00 #x00       ;; mov    $0x1,%ebx
          #xb8 #x04 #x00 #x00 #x00       ;; mov    $0x4,%eax
          #xcd #x80                      ;; int    $0x80
          ))

(define (i386:exit code)
  `(
    #xbb ,@(int->bv32 code)        ;; mov    $code,%ebx
         #xb8 #x01 #x00 #x00 #x00       ;; mov    $0x1,%eax
         #xcd #x80                      ;; int    $0x80
         ))

(define data
  (string->list "Hello, world!\n"))

(define (text d)
  (append
   (i386:puts d (length data))
   (i386:exit 0)
   ))

(define (write-any x) (write-char (if (char? x) x (integer->char x))))
(map write-any (make-elf text data))