text: /* Stack executability handling for GNU dynamic linker.  Hurd version.
     Copyright (C) 2004 Free Software Foundation, Inc.
     This file is part of the GNU C Library.
  
     The GNU C Library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Lesser General Public
     License as published by the Free Software Foundation; either
     version 2.1 of the License, or (at your option) any later version.
  
     The GNU C Library 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
     Lesser General Public License for more details.
  
     You should have received a copy of the GNU Lesser General Public
     License along with the GNU C Library; if not, see
     <http://www.gnu.org/licenses/>.  */
  
  #include <ldsodefs.h>
  #include <hurdstartup.h>
  #include <errno.h>
  
  extern struct hurd_startup_data *_dl_hurd_data attribute_hidden;
  
  /* There is no portable way to know the bounds of the initial thread's stack
     so as to mprotect it.  */
  
  int
  internal_function
  _dl_make_stack_executable (void **stack_endp)
  {
    /* Challenge the caller.  */
    if (__builtin_expect (*stack_endp != __libc_stack_end, 0))
      return EPERM;
    *stack_endp = NULL;
  
  #ifdef IS_IN_rtld
    if (__mprotect ((void *)_dl_hurd_data->stack_base, _dl_hurd_data->stack_size,
  		  PROT_READ|PROT_WRITE|PROT_EXEC) != 0)
      return errno;
  
    /* Remember that we changed the permission.  */
    GL(dl_stack_flags) |= PF_X;
  
    return 0;
  #else
    /* We don't bother to implement this for static linking.  */
    return ENOSYS;
  #endif
  }
  rtld_hidden_def (_dl_make_stack_executable)
  