uclibc-ng/libc/sysdeps/linux/avr32/clone.c

/*
 * Copyright (C) 2004 Atmel Corporation
 *
 * This file is subject to the terms and conditions of the GNU Lesser General
 * Public License.  See the file "COPYING.LIB" in the main directory of this
 * archive for more details.
 */
#include <errno.h>
#include <sys/syscall.h>
#include <unistd.h>

/*
 * I don't know if we can be absolutely certain that the fn and arg
 * parameters are preserved when returning as the child. If the
 * compiler stores them in registers (r0-r7), they should be.
 */
int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg)
{
       register int (*_fn)(void *arg) = fn;
       register void *_arg = arg;
       int err;

       /* Sanity check the arguments */
       err = -EINVAL;
       if (!fn)
               goto syscall_error;
       if (!child_stack)
               goto syscall_error;

       err = INLINE_SYSCALL(clone, 2, flags, child_stack);
       if (err < 0)
               goto syscall_error;
       else if (err != 0)
               return err;

       _exit(_fn(_arg));

syscall_error:
       __set_errno (-err);
       return -1;
}