glibc/sysdeps/mach/hurd/tls.h

/* Definitions for thread-local data handling.  Hurd version.
   Copyright (C) 2003, 2005, 2007 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, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#ifndef _TLS_H
#define _TLS_H

#if defined HAVE_TLS_SUPPORT && !defined __ASSEMBLER__

# include <stddef.h>
# include <stdbool.h>
# include <mach/mig_errors.h>
# include <mach.h>


/* Type for the dtv.  */
typedef union dtv
{
  size_t counter;
  struct
  {
    void *val;
    bool is_static;
  } pointer;
} dtv_t;


/* Type of the TCB.  */
typedef struct
{
  void *tcb;			/* Points to this structure.  */
  dtv_t *dtv;			/* Vector of pointers to TLS data.  */
  thread_t self;		/* This thread's control port.  */
} tcbhead_t;


/* This is the size of the initial TCB.  */
# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)

/* Alignment requirements for the initial TCB.  */
# define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t)

/* This is the size of the TCB.  */
# define TLS_TCB_SIZE TLS_INIT_TCB_SIZE	/* XXX */

/* Alignment requirements for the TCB.  */
# define TLS_TCB_ALIGN TLS_INIT_TCB_ALIGN /* XXX */


/* Install the dtv pointer.  The pointer passed is to the element with
   index -1 which contain the length.  */
# define INSTALL_DTV(descr, dtvp) \
  ((tcbhead_t *) (descr))->dtv = (dtvp) + 1

/* Return dtv of given thread descriptor.  */
# define GET_DTV(descr) \
  (((tcbhead_t *) (descr))->dtv)

#endif /* HAVE_TLS_SUPPORT */


#endif /* tls.h */