mes/lib/x86-mes-gcc/setjmp.c

51 lines
1.4 KiB
C

/* -*-comment-start: "//";comment-end:""-*-
* GNU Mes --- Maxwell Equations of Software
* Copyright © 2017,2018,2019 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
*
* 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 <http://www.gnu.org/licenses/>.
*/
#include <setjmp.h>
#include <stdlib.h>
void
longjmp (jmp_buf env, int val)
{
val = val == 0 ? 1 : val;
// *INDENT-OFF*
asm (
"mov 0x8(%ebp),%ebp\n\t" // env*
"mov 0x4(%ebp),%ebx\n\t" // env->__pc
"mov 0x8(%ebp),%esp\n\t" // env->__sp
"mov 0x0(%ebp),%ebp\n\t" // env->__bp
"jmp *%ebx\n\t" // jmp *PC
);
// *INDENT-ON*
// not reached
exit (42);
}
int
setjmp (jmp_buf env)
{
long *p = (long *) &env;
env[0].__bp = p[-2];
env[0].__pc = p[-1];
env[0].__sp = (long) &env;
return 0;
}