/* -*-comment-start: "//";comment-end:""-*- * GNU Mes --- Maxwell Equations of Software * Copyright © 2017,2018 Jan (janneke) Nieuwenhuizen * * This file is part of GNU Mes. * * GNU 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. * * GNU 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 GNU Mes. If not, see . */ #include #if 0 #include #define _write _xwrite #define write xwrite #define strlen xstrlen #define oputs xoputs #if __GNUC__ #define SYS_write "0x01" #define SYS_exit "0x3c" ssize_t _write (int filedes, void const *buffer, size_t size) { long r; asm ( "mov $"SYS_write",%%rax\n\t" "mov %1,%%rdi\n\t" "mov %2,%%rsi\n\t" "mov %3,%%rdx\n\t" "syscall \n\t" "mov %%rax,%0\n\t" : "=r" (r) : "rm" (filedes), "rm" (buffer), "rm" (size) : "rax", "rdi", "rsi", "rdx" ); return r; } #else #define SYS_write 0x01 #define SYS_exit 0x3c void _write (int filedes, void const *buffer, size_t size) { asm ("mov____0x8(%rbp),%rdi !0x10"); asm ("mov____0x8(%rbp),%rsi !0x18"); asm ("mov____0x8(%rbp),%rdx !0x20"); asm ("mov____$i32,%rax SYS_write"); asm ("syscall"); } #endif ssize_t write (int filedes, void const *buffer, size_t size) { int r = _write (filedes, buffer, size); if (r < 0) { errno = -r; r = -1; } else errno = 0; return r; } size_t strlen (char const* s) { int i = 0; while (s[i]) i++; return i; } int oputs (char const* s) { int i = strlen (s); write (1, s, i); return 0; } #endif int main () { oputs ("\n"); oputs ("mes\n"); return 0; }