libc/sysdeps/linux/avr32/clone.c

   1 /*
   2  * Copyright (C) 2004 Atmel Corporation
   3  *
   4  * This file is subject to the terms and conditions of the GNU Lesser General
   5  * Public License.  See the file "COPYING.LIB" in the main directory of this
   6  * archive for more details.
   7  */
   8 #include <sched.h>
   9 #include <errno.h>
  10 #include <sys/syscall.h>
  11 #include <unistd.h>
  12
  13 /*
  14  * I don't know if we can be absolutely certain that the fn and arg
  15  * parameters are preserved when returning as the child. If the
  16  * compiler stores them in registers (r0-r7), they should be.
  17  */
  18 int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg, ...)
  19 {
  20         register int (*_fn)(void *arg) = fn;
  21         register void *_arg = arg;
  22         int err;
  23
  24         /* Sanity check the arguments */
  25         err = -EINVAL;
  26         if (!fn)
  27                 goto syscall_error;
  28         if (!child_stack)
  29                 goto syscall_error;
  30
  31         err = INLINE_SYSCALL(clone, 2, flags, child_stack);
  32         if (err < 0)
  33                 goto syscall_error;
  34         else if (err != 0)
  35                 return err;
  36
  37         _exit(_fn(_arg));
  38
  39 syscall_error:
  40         __set_errno (-err);
  41         return -1;
  42 }